xref: /freebsd/sys/arm/arm/pmap-v6.c (revision 0957b409)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause AND BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 1991 Regents of the University of California.
5  * Copyright (c) 1994 John S. Dyson
6  * Copyright (c) 1994 David Greenman
7  * Copyright (c) 2005-2010 Alan L. Cox <alc@cs.rice.edu>
8  * Copyright (c) 2014-2016 Svatopluk Kraus <skra@FreeBSD.org>
9  * Copyright (c) 2014-2016 Michal Meloun <mmel@FreeBSD.org>
10  * All rights reserved.
11  *
12  * This code is derived from software contributed to Berkeley by
13  * the Systems Programming Group of the University of Utah Computer
14  * Science Department and William Jolitz of UUNET Technologies Inc.
15  *
16  * Redistribution and use in source and binary forms, with or without
17  * modification, are permitted provided that the following conditions
18  * are met:
19  * 1. Redistributions of source code must retain the above copyright
20  *    notice, this list of conditions and the following disclaimer.
21  * 2. Redistributions in binary form must reproduce the above copyright
22  *    notice, this list of conditions and the following disclaimer in the
23  *    documentation and/or other materials provided with the distribution.
24  * 3. Neither the name of the University nor the names of its contributors
25  *    may be used to endorse or promote products derived from this software
26  *    without specific prior written permission.
27  *
28  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38  * SUCH DAMAGE.
39  *
40  *	from:	@(#)pmap.c	7.7 (Berkeley)	5/12/91
41  */
42 /*-
43  * Copyright (c) 2003 Networks Associates Technology, Inc.
44  * All rights reserved.
45  *
46  * This software was developed for the FreeBSD Project by Jake Burkholder,
47  * Safeport Network Services, and Network Associates Laboratories, the
48  * Security Research Division of Network Associates, Inc. under
49  * DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA
50  * CHATS research program.
51  *
52  * Redistribution and use in source and binary forms, with or without
53  * modification, are permitted provided that the following conditions
54  * are met:
55  * 1. Redistributions of source code must retain the above copyright
56  *    notice, this list of conditions and the following disclaimer.
57  * 2. Redistributions in binary form must reproduce the above copyright
58  *    notice, this list of conditions and the following disclaimer in the
59  *    documentation and/or other materials provided with the distribution.
60  *
61  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
62  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
63  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
64  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
65  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
66  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
67  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
68  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
69  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
70  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
71  * SUCH DAMAGE.
72  */
73 
74 #include <sys/cdefs.h>
75 __FBSDID("$FreeBSD$");
76 
77 /*
78  *	Manages physical address maps.
79  *
80  *	Since the information managed by this module is
81  *	also stored by the logical address mapping module,
82  *	this module may throw away valid virtual-to-physical
83  *	mappings at almost any time.  However, invalidations
84  *	of virtual-to-physical mappings must be done as
85  *	requested.
86  *
87  *	In order to cope with hardware architectures which
88  *	make virtual-to-physical map invalidates expensive,
89  *	this module may delay invalidate or reduced protection
90  *	operations until such time as they are actually
91  *	necessary.  This module is given full information as
92  *	to which processors are currently using which maps,
93  *	and to when physical maps must be made correct.
94  */
95 
96 #include "opt_vm.h"
97 #include "opt_pmap.h"
98 #include "opt_ddb.h"
99 
100 #include <sys/param.h>
101 #include <sys/systm.h>
102 #include <sys/kernel.h>
103 #include <sys/ktr.h>
104 #include <sys/lock.h>
105 #include <sys/proc.h>
106 #include <sys/rwlock.h>
107 #include <sys/malloc.h>
108 #include <sys/vmmeter.h>
109 #include <sys/malloc.h>
110 #include <sys/mman.h>
111 #include <sys/sf_buf.h>
112 #include <sys/smp.h>
113 #include <sys/sched.h>
114 #include <sys/sysctl.h>
115 
116 #ifdef DDB
117 #include <ddb/ddb.h>
118 #endif
119 
120 #include <machine/physmem.h>
121 
122 #include <vm/vm.h>
123 #include <vm/uma.h>
124 #include <vm/pmap.h>
125 #include <vm/vm_param.h>
126 #include <vm/vm_kern.h>
127 #include <vm/vm_object.h>
128 #include <vm/vm_map.h>
129 #include <vm/vm_page.h>
130 #include <vm/vm_pageout.h>
131 #include <vm/vm_phys.h>
132 #include <vm/vm_extern.h>
133 #include <vm/vm_reserv.h>
134 #include <sys/lock.h>
135 #include <sys/mutex.h>
136 
137 #include <machine/md_var.h>
138 #include <machine/pmap_var.h>
139 #include <machine/cpu.h>
140 #include <machine/pcb.h>
141 #include <machine/sf_buf.h>
142 #ifdef SMP
143 #include <machine/smp.h>
144 #endif
145 #ifndef PMAP_SHPGPERPROC
146 #define PMAP_SHPGPERPROC 200
147 #endif
148 
149 #ifndef DIAGNOSTIC
150 #define PMAP_INLINE	__inline
151 #else
152 #define PMAP_INLINE
153 #endif
154 
155 #ifdef PMAP_DEBUG
156 static void pmap_zero_page_check(vm_page_t m);
157 void pmap_debug(int level);
158 int pmap_pid_dump(int pid);
159 
160 #define PDEBUG(_lev_,_stat_) \
161 	if (pmap_debug_level >= (_lev_)) \
162 		((_stat_))
163 #define dprintf printf
164 int pmap_debug_level = 1;
165 #else   /* PMAP_DEBUG */
166 #define PDEBUG(_lev_,_stat_) /* Nothing */
167 #define dprintf(x, arg...)
168 #endif  /* PMAP_DEBUG */
169 
170 /*
171  *  Level 2 page tables map definion ('max' is excluded).
172  */
173 
174 #define PT2V_MIN_ADDRESS	((vm_offset_t)PT2MAP)
175 #define PT2V_MAX_ADDRESS	((vm_offset_t)PT2MAP + PT2MAP_SIZE)
176 
177 #define UPT2V_MIN_ADDRESS	((vm_offset_t)PT2MAP)
178 #define UPT2V_MAX_ADDRESS \
179     ((vm_offset_t)(PT2MAP + (KERNBASE >> PT2MAP_SHIFT)))
180 
181 /*
182  *  Promotion to a 1MB (PTE1) page mapping requires that the corresponding
183  *  4KB (PTE2) page mappings have identical settings for the following fields:
184  */
185 #define PTE2_PROMOTE	(PTE2_V | PTE2_A | PTE2_NM | PTE2_S | PTE2_NG |	\
186 			 PTE2_NX | PTE2_RO | PTE2_U | PTE2_W |		\
187 			 PTE2_ATTR_MASK)
188 
189 #define PTE1_PROMOTE	(PTE1_V | PTE1_A | PTE1_NM | PTE1_S | PTE1_NG |	\
190 			 PTE1_NX | PTE1_RO | PTE1_U | PTE1_W |		\
191 			 PTE1_ATTR_MASK)
192 
193 #define ATTR_TO_L1(l2_attr)	((((l2_attr) & L2_TEX0) ? L1_S_TEX0 : 0) | \
194 				 (((l2_attr) & L2_C)    ? L1_S_C    : 0) | \
195 				 (((l2_attr) & L2_B)    ? L1_S_B    : 0) | \
196 				 (((l2_attr) & PTE2_A)  ? PTE1_A    : 0) | \
197 				 (((l2_attr) & PTE2_NM) ? PTE1_NM   : 0) | \
198 				 (((l2_attr) & PTE2_S)  ? PTE1_S    : 0) | \
199 				 (((l2_attr) & PTE2_NG) ? PTE1_NG   : 0) | \
200 				 (((l2_attr) & PTE2_NX) ? PTE1_NX   : 0) | \
201 				 (((l2_attr) & PTE2_RO) ? PTE1_RO   : 0) | \
202 				 (((l2_attr) & PTE2_U)  ? PTE1_U    : 0) | \
203 				 (((l2_attr) & PTE2_W)  ? PTE1_W    : 0))
204 
205 #define ATTR_TO_L2(l1_attr)	((((l1_attr) & L1_S_TEX0) ? L2_TEX0 : 0) | \
206 				 (((l1_attr) & L1_S_C)    ? L2_C    : 0) | \
207 				 (((l1_attr) & L1_S_B)    ? L2_B    : 0) | \
208 				 (((l1_attr) & PTE1_A)    ? PTE2_A  : 0) | \
209 				 (((l1_attr) & PTE1_NM)   ? PTE2_NM : 0) | \
210 				 (((l1_attr) & PTE1_S)    ? PTE2_S  : 0) | \
211 				 (((l1_attr) & PTE1_NG)   ? PTE2_NG : 0) | \
212 				 (((l1_attr) & PTE1_NX)   ? PTE2_NX : 0) | \
213 				 (((l1_attr) & PTE1_RO)   ? PTE2_RO : 0) | \
214 				 (((l1_attr) & PTE1_U)    ? PTE2_U  : 0) | \
215 				 (((l1_attr) & PTE1_W)    ? PTE2_W  : 0))
216 
217 /*
218  *  PTE2 descriptors creation macros.
219  */
220 #define PTE2_ATTR_DEFAULT	vm_memattr_to_pte2(VM_MEMATTR_DEFAULT)
221 #define PTE2_ATTR_PT		vm_memattr_to_pte2(pt_memattr)
222 
223 #define PTE2_KPT(pa)	PTE2_KERN(pa, PTE2_AP_KRW, PTE2_ATTR_PT)
224 #define PTE2_KPT_NG(pa)	PTE2_KERN_NG(pa, PTE2_AP_KRW, PTE2_ATTR_PT)
225 
226 #define PTE2_KRW(pa)	PTE2_KERN(pa, PTE2_AP_KRW, PTE2_ATTR_DEFAULT)
227 #define PTE2_KRO(pa)	PTE2_KERN(pa, PTE2_AP_KR, PTE2_ATTR_DEFAULT)
228 
229 #define PV_STATS
230 #ifdef PV_STATS
231 #define PV_STAT(x)	do { x ; } while (0)
232 #else
233 #define PV_STAT(x)	do { } while (0)
234 #endif
235 
236 /*
237  *  The boot_pt1 is used temporary in very early boot stage as L1 page table.
238  *  We can init many things with no memory allocation thanks to its static
239  *  allocation and this brings two main advantages:
240  *  (1) other cores can be started very simply,
241  *  (2) various boot loaders can be supported as its arguments can be processed
242  *      in virtual address space and can be moved to safe location before
243  *      first allocation happened.
244  *  Only disadvantage is that boot_pt1 is used only in very early boot stage.
245  *  However, the table is uninitialized and so lays in bss. Therefore kernel
246  *  image size is not influenced.
247  *
248  *  QQQ: In the future, maybe, boot_pt1 can be used for soft reset and
249  *       CPU suspend/resume game.
250  */
251 extern pt1_entry_t boot_pt1[];
252 
253 vm_paddr_t base_pt1;
254 pt1_entry_t *kern_pt1;
255 pt2_entry_t *kern_pt2tab;
256 pt2_entry_t *PT2MAP;
257 
258 static uint32_t ttb_flags;
259 static vm_memattr_t pt_memattr;
260 ttb_entry_t pmap_kern_ttb;
261 
262 struct pmap kernel_pmap_store;
263 LIST_HEAD(pmaplist, pmap);
264 static struct pmaplist allpmaps;
265 static struct mtx allpmaps_lock;
266 
267 vm_offset_t virtual_avail;	/* VA of first avail page (after kernel bss) */
268 vm_offset_t virtual_end;	/* VA of last avail page (end of kernel AS) */
269 
270 static vm_offset_t kernel_vm_end_new;
271 vm_offset_t kernel_vm_end = KERNBASE + NKPT2PG * NPT2_IN_PG * PTE1_SIZE;
272 vm_offset_t vm_max_kernel_address;
273 vm_paddr_t kernel_l1pa;
274 
275 static struct rwlock __aligned(CACHE_LINE_SIZE) pvh_global_lock;
276 
277 /*
278  *  Data for the pv entry allocation mechanism
279  */
280 static TAILQ_HEAD(pch, pv_chunk) pv_chunks = TAILQ_HEAD_INITIALIZER(pv_chunks);
281 static int pv_entry_count = 0, pv_entry_max = 0, pv_entry_high_water = 0;
282 static struct md_page *pv_table; /* XXX: Is it used only the list in md_page? */
283 static int shpgperproc = PMAP_SHPGPERPROC;
284 
285 struct pv_chunk *pv_chunkbase;		/* KVA block for pv_chunks */
286 int pv_maxchunks;			/* How many chunks we have KVA for */
287 vm_offset_t pv_vafree;			/* freelist stored in the PTE */
288 
289 vm_paddr_t first_managed_pa;
290 #define	pa_to_pvh(pa)	(&pv_table[pte1_index(pa - first_managed_pa)])
291 
292 /*
293  *  All those kernel PT submaps that BSD is so fond of
294  */
295 caddr_t _tmppt = 0;
296 
297 /*
298  *  Crashdump maps.
299  */
300 static caddr_t crashdumpmap;
301 
302 static pt2_entry_t *PMAP1 = NULL, *PMAP2;
303 static pt2_entry_t *PADDR1 = NULL, *PADDR2;
304 #ifdef DDB
305 static pt2_entry_t *PMAP3;
306 static pt2_entry_t *PADDR3;
307 static int PMAP3cpu __unused; /* for SMP only */
308 #endif
309 #ifdef SMP
310 static int PMAP1cpu;
311 static int PMAP1changedcpu;
312 SYSCTL_INT(_debug, OID_AUTO, PMAP1changedcpu, CTLFLAG_RD,
313     &PMAP1changedcpu, 0,
314     "Number of times pmap_pte2_quick changed CPU with same PMAP1");
315 #endif
316 static int PMAP1changed;
317 SYSCTL_INT(_debug, OID_AUTO, PMAP1changed, CTLFLAG_RD,
318     &PMAP1changed, 0,
319     "Number of times pmap_pte2_quick changed PMAP1");
320 static int PMAP1unchanged;
321 SYSCTL_INT(_debug, OID_AUTO, PMAP1unchanged, CTLFLAG_RD,
322     &PMAP1unchanged, 0,
323     "Number of times pmap_pte2_quick didn't change PMAP1");
324 static struct mtx PMAP2mutex;
325 
326 /*
327  * Internal flags for pmap_enter()'s helper functions.
328  */
329 #define	PMAP_ENTER_NORECLAIM	0x1000000	/* Don't reclaim PV entries. */
330 #define	PMAP_ENTER_NOREPLACE	0x2000000	/* Don't replace mappings. */
331 
332 static __inline void pt2_wirecount_init(vm_page_t m);
333 static boolean_t pmap_demote_pte1(pmap_t pmap, pt1_entry_t *pte1p,
334     vm_offset_t va);
335 static int pmap_enter_pte1(pmap_t pmap, vm_offset_t va, pt1_entry_t pte1,
336     u_int flags, vm_page_t m);
337 void cache_icache_sync_fresh(vm_offset_t va, vm_paddr_t pa, vm_size_t size);
338 
339 /*
340  *  Function to set the debug level of the pmap code.
341  */
342 #ifdef PMAP_DEBUG
343 void
344 pmap_debug(int level)
345 {
346 
347 	pmap_debug_level = level;
348 	dprintf("pmap_debug: level=%d\n", pmap_debug_level);
349 }
350 #endif /* PMAP_DEBUG */
351 
352 /*
353  *  This table must corespond with memory attribute configuration in vm.h.
354  *  First entry is used for normal system mapping.
355  *
356  *  Device memory is always marked as shared.
357  *  Normal memory is shared only in SMP .
358  *  Not outer shareable bits are not used yet.
359  *  Class 6 cannot be used on ARM11.
360  */
361 #define TEXDEF_TYPE_SHIFT	0
362 #define TEXDEF_TYPE_MASK	0x3
363 #define TEXDEF_INNER_SHIFT	2
364 #define TEXDEF_INNER_MASK	0x3
365 #define TEXDEF_OUTER_SHIFT	4
366 #define TEXDEF_OUTER_MASK	0x3
367 #define TEXDEF_NOS_SHIFT	6
368 #define TEXDEF_NOS_MASK		0x1
369 
370 #define TEX(t, i, o, s) 			\
371 		((t) << TEXDEF_TYPE_SHIFT) |	\
372 		((i) << TEXDEF_INNER_SHIFT) |	\
373 		((o) << TEXDEF_OUTER_SHIFT | 	\
374 		((s) << TEXDEF_NOS_SHIFT))
375 
376 static uint32_t tex_class[8] = {
377 /*	    type      inner cache outer cache */
378 	TEX(PRRR_MEM, NMRR_WB_WA, NMRR_WB_WA, 0),  /* 0 - ATTR_WB_WA	*/
379 	TEX(PRRR_MEM, NMRR_NC,	  NMRR_NC,    0),  /* 1 - ATTR_NOCACHE	*/
380 	TEX(PRRR_DEV, NMRR_NC,	  NMRR_NC,    0),  /* 2 - ATTR_DEVICE	*/
381 	TEX(PRRR_SO,  NMRR_NC,	  NMRR_NC,    0),  /* 3 - ATTR_SO	*/
382 	TEX(PRRR_MEM, NMRR_WT,	  NMRR_WT,    0),  /* 4 - ATTR_WT	*/
383 	TEX(PRRR_MEM, NMRR_NC,	  NMRR_NC,    0),  /* 5 - NOT USED YET	*/
384 	TEX(PRRR_MEM, NMRR_NC,	  NMRR_NC,    0),  /* 6 - NOT USED YET	*/
385 	TEX(PRRR_MEM, NMRR_NC,	  NMRR_NC,    0),  /* 7 - NOT USED YET	*/
386 };
387 #undef TEX
388 
389 static uint32_t pte2_attr_tab[8] = {
390 	PTE2_ATTR_WB_WA,	/* 0 - VM_MEMATTR_WB_WA */
391 	PTE2_ATTR_NOCACHE,	/* 1 - VM_MEMATTR_NOCACHE */
392 	PTE2_ATTR_DEVICE,	/* 2 - VM_MEMATTR_DEVICE */
393 	PTE2_ATTR_SO,		/* 3 - VM_MEMATTR_SO */
394 	PTE2_ATTR_WT,		/* 4 - VM_MEMATTR_WRITE_THROUGH */
395 	0,			/* 5 - NOT USED YET */
396 	0,			/* 6 - NOT USED YET */
397 	0			/* 7 - NOT USED YET */
398 };
399 CTASSERT(VM_MEMATTR_WB_WA == 0);
400 CTASSERT(VM_MEMATTR_NOCACHE == 1);
401 CTASSERT(VM_MEMATTR_DEVICE == 2);
402 CTASSERT(VM_MEMATTR_SO == 3);
403 CTASSERT(VM_MEMATTR_WRITE_THROUGH == 4);
404 #define	VM_MEMATTR_END	(VM_MEMATTR_WRITE_THROUGH + 1)
405 
406 boolean_t
407 pmap_is_valid_memattr(pmap_t pmap __unused, vm_memattr_t mode)
408 {
409 
410 	return (mode >= 0 && mode < VM_MEMATTR_END);
411 }
412 
413 static inline uint32_t
414 vm_memattr_to_pte2(vm_memattr_t ma)
415 {
416 
417 	KASSERT((u_int)ma < VM_MEMATTR_END,
418 	    ("%s: bad vm_memattr_t %d", __func__, ma));
419 	return (pte2_attr_tab[(u_int)ma]);
420 }
421 
422 static inline uint32_t
423 vm_page_pte2_attr(vm_page_t m)
424 {
425 
426 	return (vm_memattr_to_pte2(m->md.pat_mode));
427 }
428 
429 /*
430  * Convert TEX definition entry to TTB flags.
431  */
432 static uint32_t
433 encode_ttb_flags(int idx)
434 {
435 	uint32_t inner, outer, nos, reg;
436 
437 	inner = (tex_class[idx] >> TEXDEF_INNER_SHIFT) &
438 		TEXDEF_INNER_MASK;
439 	outer = (tex_class[idx] >> TEXDEF_OUTER_SHIFT) &
440 		TEXDEF_OUTER_MASK;
441 	nos = (tex_class[idx] >> TEXDEF_NOS_SHIFT) &
442 		TEXDEF_NOS_MASK;
443 
444 	reg = nos << 5;
445 	reg |= outer << 3;
446 	if (cpuinfo.coherent_walk)
447 		reg |= (inner & 0x1) << 6;
448 	reg |= (inner & 0x2) >> 1;
449 #ifdef SMP
450 	ARM_SMP_UP(
451 		reg |= 1 << 1,
452 	);
453 #endif
454 	return reg;
455 }
456 
457 /*
458  *  Set TEX remapping registers in current CPU.
459  */
460 void
461 pmap_set_tex(void)
462 {
463 	uint32_t prrr, nmrr;
464 	uint32_t type, inner, outer, nos;
465 	int i;
466 
467 #ifdef PMAP_PTE_NOCACHE
468 	/* XXX fixme */
469 	if (cpuinfo.coherent_walk) {
470 		pt_memattr = VM_MEMATTR_WB_WA;
471 		ttb_flags = encode_ttb_flags(0);
472 	}
473 	else {
474 		pt_memattr = VM_MEMATTR_NOCACHE;
475 		ttb_flags = encode_ttb_flags(1);
476 	}
477 #else
478 	pt_memattr = VM_MEMATTR_WB_WA;
479 	ttb_flags = encode_ttb_flags(0);
480 #endif
481 
482 	prrr = 0;
483 	nmrr = 0;
484 
485 	/* Build remapping register from TEX classes. */
486 	for (i = 0; i < 8; i++) {
487 		type = (tex_class[i] >> TEXDEF_TYPE_SHIFT) &
488 			TEXDEF_TYPE_MASK;
489 		inner = (tex_class[i] >> TEXDEF_INNER_SHIFT) &
490 			TEXDEF_INNER_MASK;
491 		outer = (tex_class[i] >> TEXDEF_OUTER_SHIFT) &
492 			TEXDEF_OUTER_MASK;
493 		nos = (tex_class[i] >> TEXDEF_NOS_SHIFT) &
494 			TEXDEF_NOS_MASK;
495 
496 		prrr |= type  << (i * 2);
497 		prrr |= nos   << (i + 24);
498 		nmrr |= inner << (i * 2);
499 		nmrr |= outer << (i * 2 + 16);
500 	}
501 	/* Add shareable bits for device memory. */
502 	prrr |= PRRR_DS0 | PRRR_DS1;
503 
504 	/* Add shareable bits for normal memory in SMP case. */
505 #ifdef SMP
506 	ARM_SMP_UP(
507 		prrr |= PRRR_NS1,
508 	);
509 #endif
510 	cp15_prrr_set(prrr);
511 	cp15_nmrr_set(nmrr);
512 
513 	/* Caches are disabled, so full TLB flush should be enough. */
514 	tlb_flush_all_local();
515 }
516 
517 /*
518  * Remap one vm_meattr class to another one. This can be useful as
519  * workaround for SOC errata, e.g. if devices must be accessed using
520  * SO memory class.
521  *
522  * !!! Please note that this function is absolutely last resort thing.
523  * It should not be used under normal circumstances. !!!
524  *
525  * Usage rules:
526  * - it shall be called after pmap_bootstrap_prepare() and before
527  *   cpu_mp_start() (thus only on boot CPU). In practice, it's expected
528  *   to be called from platform_attach() or platform_late_init().
529  *
530  * - if remapping doesn't change caching mode, or until uncached class
531  *   is remapped to any kind of cached one, then no other restriction exists.
532  *
533  * - if pmap_remap_vm_attr() changes caching mode, but both (original and
534  *   remapped) remain cached, then caller is resposible for calling
535  *   of dcache_wbinv_poc_all().
536  *
537  * - remapping of any kind of cached class to uncached is not permitted.
538  */
539 void
540 pmap_remap_vm_attr(vm_memattr_t old_attr, vm_memattr_t new_attr)
541 {
542 	int old_idx, new_idx;
543 
544 	/* Map VM memattrs to indexes to tex_class table. */
545 	old_idx = PTE2_ATTR2IDX(pte2_attr_tab[(int)old_attr]);
546 	new_idx = PTE2_ATTR2IDX(pte2_attr_tab[(int)new_attr]);
547 
548 	/* Replace TEX attribute and apply it. */
549 	tex_class[old_idx] = tex_class[new_idx];
550 	pmap_set_tex();
551 }
552 
553 /*
554  * KERNBASE must be multiple of NPT2_IN_PG * PTE1_SIZE. In other words,
555  * KERNBASE is mapped by first L2 page table in L2 page table page. It
556  * meets same constrain due to PT2MAP being placed just under KERNBASE.
557  */
558 CTASSERT((KERNBASE & (NPT2_IN_PG * PTE1_SIZE - 1)) == 0);
559 CTASSERT((KERNBASE - VM_MAXUSER_ADDRESS) >= PT2MAP_SIZE);
560 
561 /*
562  *  In crazy dreams, PAGE_SIZE could be a multiple of PTE2_SIZE in general.
563  *  For now, anyhow, the following check must be fulfilled.
564  */
565 CTASSERT(PAGE_SIZE == PTE2_SIZE);
566 /*
567  *  We don't want to mess up MI code with all MMU and PMAP definitions,
568  *  so some things, which depend on other ones, are defined independently.
569  *  Now, it is time to check that we don't screw up something.
570  */
571 CTASSERT(PDRSHIFT == PTE1_SHIFT);
572 /*
573  *  Check L1 and L2 page table entries definitions consistency.
574  */
575 CTASSERT(NB_IN_PT1 == (sizeof(pt1_entry_t) * NPTE1_IN_PT1));
576 CTASSERT(NB_IN_PT2 == (sizeof(pt2_entry_t) * NPTE2_IN_PT2));
577 /*
578  *  Check L2 page tables page consistency.
579  */
580 CTASSERT(PAGE_SIZE == (NPT2_IN_PG * NB_IN_PT2));
581 CTASSERT((1 << PT2PG_SHIFT) == NPT2_IN_PG);
582 /*
583  *  Check PT2TAB consistency.
584  *  PT2TAB_ENTRIES is defined as a division of NPTE1_IN_PT1 by NPT2_IN_PG.
585  *  This should be done without remainder.
586  */
587 CTASSERT(NPTE1_IN_PT1 == (PT2TAB_ENTRIES * NPT2_IN_PG));
588 
589 /*
590  *	A PT2MAP magic.
591  *
592  *  All level 2 page tables (PT2s) are mapped continuously and accordingly
593  *  into PT2MAP address space. As PT2 size is less than PAGE_SIZE, this can
594  *  be done only if PAGE_SIZE is a multiple of PT2 size. All PT2s in one page
595  *  must be used together, but not necessary at once. The first PT2 in a page
596  *  must map things on correctly aligned address and the others must follow
597  *  in right order.
598  */
599 #define NB_IN_PT2TAB	(PT2TAB_ENTRIES * sizeof(pt2_entry_t))
600 #define NPT2_IN_PT2TAB	(NB_IN_PT2TAB / NB_IN_PT2)
601 #define NPG_IN_PT2TAB	(NB_IN_PT2TAB / PAGE_SIZE)
602 
603 /*
604  *  Check PT2TAB consistency.
605  *  NPT2_IN_PT2TAB is defined as a division of NB_IN_PT2TAB by NB_IN_PT2.
606  *  NPG_IN_PT2TAB is defined as a division of NB_IN_PT2TAB by PAGE_SIZE.
607  *  The both should be done without remainder.
608  */
609 CTASSERT(NB_IN_PT2TAB == (NPT2_IN_PT2TAB * NB_IN_PT2));
610 CTASSERT(NB_IN_PT2TAB == (NPG_IN_PT2TAB * PAGE_SIZE));
611 /*
612  *  The implementation was made general, however, with the assumption
613  *  bellow in mind. In case of another value of NPG_IN_PT2TAB,
614  *  the code should be once more rechecked.
615  */
616 CTASSERT(NPG_IN_PT2TAB == 1);
617 
618 /*
619  *  Get offset of PT2 in a page
620  *  associated with given PT1 index.
621  */
622 static __inline u_int
623 page_pt2off(u_int pt1_idx)
624 {
625 
626 	return ((pt1_idx & PT2PG_MASK) * NB_IN_PT2);
627 }
628 
629 /*
630  *  Get physical address of PT2
631  *  associated with given PT2s page and PT1 index.
632  */
633 static __inline vm_paddr_t
634 page_pt2pa(vm_paddr_t pgpa, u_int pt1_idx)
635 {
636 
637 	return (pgpa + page_pt2off(pt1_idx));
638 }
639 
640 /*
641  *  Get first entry of PT2
642  *  associated with given PT2s page and PT1 index.
643  */
644 static __inline pt2_entry_t *
645 page_pt2(vm_offset_t pgva, u_int pt1_idx)
646 {
647 
648 	return ((pt2_entry_t *)(pgva + page_pt2off(pt1_idx)));
649 }
650 
651 /*
652  *  Get virtual address of PT2s page (mapped in PT2MAP)
653  *  which holds PT2 which holds entry which maps given virtual address.
654  */
655 static __inline vm_offset_t
656 pt2map_pt2pg(vm_offset_t va)
657 {
658 
659 	va &= ~(NPT2_IN_PG * PTE1_SIZE - 1);
660 	return ((vm_offset_t)pt2map_entry(va));
661 }
662 
663 /*****************************************************************************
664  *
665  *     THREE pmap initialization milestones exist:
666  *
667  *  locore.S
668  *    -> fundamental init (including MMU) in ASM
669  *
670  *  initarm()
671  *    -> fundamental init continues in C
672  *    -> first available physical address is known
673  *
674  *    pmap_bootstrap_prepare() -> FIRST PMAP MILESTONE (first epoch begins)
675  *      -> basic (safe) interface for physical address allocation is made
676  *      -> basic (safe) interface for virtual mapping is made
677  *      -> limited not SMP coherent work is possible
678  *
679  *    -> more fundamental init continues in C
680  *    -> locks and some more things are available
681  *    -> all fundamental allocations and mappings are done
682  *
683  *    pmap_bootstrap() -> SECOND PMAP MILESTONE (second epoch begins)
684  *      -> phys_avail[] and virtual_avail is set
685  *      -> control is passed to vm subsystem
686  *      -> physical and virtual address allocation are off limit
687  *      -> low level mapping functions, some SMP coherent,
688  *         are available, which cannot be used before vm subsystem
689  *         is being inited
690  *
691  *  mi_startup()
692  *    -> vm subsystem is being inited
693  *
694  *      pmap_init() -> THIRD PMAP MILESTONE (third epoch begins)
695  *        -> pmap is fully inited
696  *
697  *****************************************************************************/
698 
699 /*****************************************************************************
700  *
701  *	PMAP first stage initialization and utility functions
702  *	for pre-bootstrap epoch.
703  *
704  *  After pmap_bootstrap_prepare() is called, the following functions
705  *  can be used:
706  *
707  *  (1) strictly only for this stage functions for physical page allocations,
708  *      virtual space allocations, and mappings:
709  *
710  *  vm_paddr_t pmap_preboot_get_pages(u_int num);
711  *  void pmap_preboot_map_pages(vm_paddr_t pa, vm_offset_t va, u_int num);
712  *  vm_offset_t pmap_preboot_reserve_pages(u_int num);
713  *  vm_offset_t pmap_preboot_get_vpages(u_int num);
714  *  void pmap_preboot_map_attr(vm_paddr_t pa, vm_offset_t va, vm_size_t size,
715  *      vm_prot_t prot, vm_memattr_t attr);
716  *
717  *  (2) for all stages:
718  *
719  *  vm_paddr_t pmap_kextract(vm_offset_t va);
720  *
721  *  NOTE: This is not SMP coherent stage.
722  *
723  *****************************************************************************/
724 
725 #define KERNEL_P2V(pa) \
726     ((vm_offset_t)((pa) - arm_physmem_kernaddr + KERNVIRTADDR))
727 #define KERNEL_V2P(va) \
728     ((vm_paddr_t)((va) - KERNVIRTADDR + arm_physmem_kernaddr))
729 
730 static vm_paddr_t last_paddr;
731 
732 /*
733  *  Pre-bootstrap epoch page allocator.
734  */
735 vm_paddr_t
736 pmap_preboot_get_pages(u_int num)
737 {
738 	vm_paddr_t ret;
739 
740 	ret = last_paddr;
741 	last_paddr += num * PAGE_SIZE;
742 
743 	return (ret);
744 }
745 
746 /*
747  *	The fundamental initialization of PMAP stuff.
748  *
749  *  Some things already happened in locore.S and some things could happen
750  *  before pmap_bootstrap_prepare() is called, so let's recall what is done:
751  *  1. Caches are disabled.
752  *  2. We are running on virtual addresses already with 'boot_pt1'
753  *     as L1 page table.
754  *  3. So far, all virtual addresses can be converted to physical ones and
755  *     vice versa by the following macros:
756  *       KERNEL_P2V(pa) .... physical to virtual ones,
757  *       KERNEL_V2P(va) .... virtual to physical ones.
758  *
759  *  What is done herein:
760  *  1. The 'boot_pt1' is replaced by real kernel L1 page table 'kern_pt1'.
761  *  2. PT2MAP magic is brought to live.
762  *  3. Basic preboot functions for page allocations and mappings can be used.
763  *  4. Everything is prepared for L1 cache enabling.
764  *
765  *  Variations:
766  *  1. To use second TTB register, so kernel and users page tables will be
767  *     separated. This way process forking - pmap_pinit() - could be faster,
768  *     it saves physical pages and KVA per a process, and it's simple change.
769  *     However, it will lead, due to hardware matter, to the following:
770  *     (a) 2G space for kernel and 2G space for users.
771  *     (b) 1G space for kernel in low addresses and 3G for users above it.
772  *     A question is: Is the case (b) really an option? Note that case (b)
773  *     does save neither physical memory and KVA.
774  */
775 void
776 pmap_bootstrap_prepare(vm_paddr_t last)
777 {
778 	vm_paddr_t pt2pg_pa, pt2tab_pa, pa, size;
779 	vm_offset_t pt2pg_va;
780 	pt1_entry_t *pte1p;
781 	pt2_entry_t *pte2p;
782 	u_int i;
783 	uint32_t l1_attr;
784 
785 	/*
786 	 * Now, we are going to make real kernel mapping. Note that we are
787 	 * already running on some mapping made in locore.S and we expect
788 	 * that it's large enough to ensure nofault access to physical memory
789 	 * allocated herein before switch.
790 	 *
791 	 * As kernel image and everything needed before are and will be mapped
792 	 * by section mappings, we align last physical address to PTE1_SIZE.
793 	 */
794 	last_paddr = pte1_roundup(last);
795 
796 	/*
797 	 * Allocate and zero page(s) for kernel L1 page table.
798 	 *
799 	 * Note that it's first allocation on space which was PTE1_SIZE
800 	 * aligned and as such base_pt1 is aligned to NB_IN_PT1 too.
801 	 */
802 	base_pt1 = pmap_preboot_get_pages(NPG_IN_PT1);
803 	kern_pt1 = (pt1_entry_t *)KERNEL_P2V(base_pt1);
804 	bzero((void*)kern_pt1, NB_IN_PT1);
805 	pte1_sync_range(kern_pt1, NB_IN_PT1);
806 
807 	/* Allocate and zero page(s) for kernel PT2TAB. */
808 	pt2tab_pa = pmap_preboot_get_pages(NPG_IN_PT2TAB);
809 	kern_pt2tab = (pt2_entry_t *)KERNEL_P2V(pt2tab_pa);
810 	bzero(kern_pt2tab, NB_IN_PT2TAB);
811 	pte2_sync_range(kern_pt2tab, NB_IN_PT2TAB);
812 
813 	/* Allocate and zero page(s) for kernel L2 page tables. */
814 	pt2pg_pa = pmap_preboot_get_pages(NKPT2PG);
815 	pt2pg_va = KERNEL_P2V(pt2pg_pa);
816 	size = NKPT2PG * PAGE_SIZE;
817 	bzero((void*)pt2pg_va, size);
818 	pte2_sync_range((pt2_entry_t *)pt2pg_va, size);
819 
820 	/*
821 	 * Add a physical memory segment (vm_phys_seg) corresponding to the
822 	 * preallocated pages for kernel L2 page tables so that vm_page
823 	 * structures representing these pages will be created. The vm_page
824 	 * structures are required for promotion of the corresponding kernel
825 	 * virtual addresses to section mappings.
826 	 */
827 	vm_phys_add_seg(pt2tab_pa, pmap_preboot_get_pages(0));
828 
829 	/*
830 	 * Insert allocated L2 page table pages to PT2TAB and make
831 	 * link to all PT2s in L1 page table. See how kernel_vm_end
832 	 * is initialized.
833 	 *
834 	 * We play simple and safe. So every KVA will have underlaying
835 	 * L2 page table, even kernel image mapped by sections.
836 	 */
837 	pte2p = kern_pt2tab_entry(KERNBASE);
838 	for (pa = pt2pg_pa; pa < pt2pg_pa + size; pa += PTE2_SIZE)
839 		pt2tab_store(pte2p++, PTE2_KPT(pa));
840 
841 	pte1p = kern_pte1(KERNBASE);
842 	for (pa = pt2pg_pa; pa < pt2pg_pa + size; pa += NB_IN_PT2)
843 		pte1_store(pte1p++, PTE1_LINK(pa));
844 
845 	/* Make section mappings for kernel. */
846 	l1_attr = ATTR_TO_L1(PTE2_ATTR_DEFAULT);
847 	pte1p = kern_pte1(KERNBASE);
848 	for (pa = KERNEL_V2P(KERNBASE); pa < last; pa += PTE1_SIZE)
849 		pte1_store(pte1p++, PTE1_KERN(pa, PTE1_AP_KRW, l1_attr));
850 
851 	/*
852 	 * Get free and aligned space for PT2MAP and make L1 page table links
853 	 * to L2 page tables held in PT2TAB.
854 	 *
855 	 * Note that pages holding PT2s are stored in PT2TAB as pt2_entry_t
856 	 * descriptors and PT2TAB page(s) itself is(are) used as PT2s. Thus
857 	 * each entry in PT2TAB maps all PT2s in a page. This implies that
858 	 * virtual address of PT2MAP must be aligned to NPT2_IN_PG * PTE1_SIZE.
859 	 */
860 	PT2MAP = (pt2_entry_t *)(KERNBASE - PT2MAP_SIZE);
861 	pte1p = kern_pte1((vm_offset_t)PT2MAP);
862 	for (pa = pt2tab_pa, i = 0; i < NPT2_IN_PT2TAB; i++, pa += NB_IN_PT2) {
863 		pte1_store(pte1p++, PTE1_LINK(pa));
864 	}
865 
866 	/*
867 	 * Store PT2TAB in PT2TAB itself, i.e. self reference mapping.
868 	 * Each pmap will hold own PT2TAB, so the mapping should be not global.
869 	 */
870 	pte2p = kern_pt2tab_entry((vm_offset_t)PT2MAP);
871 	for (pa = pt2tab_pa, i = 0; i < NPG_IN_PT2TAB; i++, pa += PTE2_SIZE) {
872 		pt2tab_store(pte2p++, PTE2_KPT_NG(pa));
873 	}
874 
875 	/*
876 	 * Choose correct L2 page table and make mappings for allocations
877 	 * made herein which replaces temporary locore.S mappings after a while.
878 	 * Note that PT2MAP cannot be used until we switch to kern_pt1.
879 	 *
880 	 * Note, that these allocations started aligned on 1M section and
881 	 * kernel PT1 was allocated first. Making of mappings must follow
882 	 * order of physical allocations as we've used KERNEL_P2V() macro
883 	 * for virtual addresses resolution.
884 	 */
885 	pte2p = kern_pt2tab_entry((vm_offset_t)kern_pt1);
886 	pt2pg_va = KERNEL_P2V(pte2_pa(pte2_load(pte2p)));
887 
888 	pte2p = page_pt2(pt2pg_va, pte1_index((vm_offset_t)kern_pt1));
889 
890 	/* Make mapping for kernel L1 page table. */
891 	for (pa = base_pt1, i = 0; i < NPG_IN_PT1; i++, pa += PTE2_SIZE)
892 		pte2_store(pte2p++, PTE2_KPT(pa));
893 
894 	/* Make mapping for kernel PT2TAB. */
895 	for (pa = pt2tab_pa, i = 0; i < NPG_IN_PT2TAB; i++, pa += PTE2_SIZE)
896 		pte2_store(pte2p++, PTE2_KPT(pa));
897 
898 	/* Finally, switch from 'boot_pt1' to 'kern_pt1'. */
899 	pmap_kern_ttb = base_pt1 | ttb_flags;
900 	cpuinfo_reinit_mmu(pmap_kern_ttb);
901 	/*
902 	 * Initialize the first available KVA. As kernel image is mapped by
903 	 * sections, we are leaving some gap behind.
904 	 */
905 	virtual_avail = (vm_offset_t)kern_pt2tab + NPG_IN_PT2TAB * PAGE_SIZE;
906 }
907 
908 /*
909  *  Setup L2 page table page for given KVA.
910  *  Used in pre-bootstrap epoch.
911  *
912  *  Note that we have allocated NKPT2PG pages for L2 page tables in advance
913  *  and used them for mapping KVA starting from KERNBASE. However, this is not
914  *  enough. Vectors and devices need L2 page tables too. Note that they are
915  *  even above VM_MAX_KERNEL_ADDRESS.
916  */
917 static __inline vm_paddr_t
918 pmap_preboot_pt2pg_setup(vm_offset_t va)
919 {
920 	pt2_entry_t *pte2p, pte2;
921 	vm_paddr_t pt2pg_pa;
922 
923 	/* Get associated entry in PT2TAB. */
924 	pte2p = kern_pt2tab_entry(va);
925 
926 	/* Just return, if PT2s page exists already. */
927 	pte2 = pt2tab_load(pte2p);
928 	if (pte2_is_valid(pte2))
929 		return (pte2_pa(pte2));
930 
931 	KASSERT(va >= VM_MAX_KERNEL_ADDRESS,
932 	    ("%s: NKPT2PG too small", __func__));
933 
934 	/*
935 	 * Allocate page for PT2s and insert it to PT2TAB.
936 	 * In other words, map it into PT2MAP space.
937 	 */
938 	pt2pg_pa = pmap_preboot_get_pages(1);
939 	pt2tab_store(pte2p, PTE2_KPT(pt2pg_pa));
940 
941 	/* Zero all PT2s in allocated page. */
942 	bzero((void*)pt2map_pt2pg(va), PAGE_SIZE);
943 	pte2_sync_range((pt2_entry_t *)pt2map_pt2pg(va), PAGE_SIZE);
944 
945 	return (pt2pg_pa);
946 }
947 
948 /*
949  *  Setup L2 page table for given KVA.
950  *  Used in pre-bootstrap epoch.
951  */
952 static void
953 pmap_preboot_pt2_setup(vm_offset_t va)
954 {
955 	pt1_entry_t *pte1p;
956 	vm_paddr_t pt2pg_pa, pt2_pa;
957 
958 	/* Setup PT2's page. */
959 	pt2pg_pa = pmap_preboot_pt2pg_setup(va);
960 	pt2_pa = page_pt2pa(pt2pg_pa, pte1_index(va));
961 
962 	/* Insert PT2 to PT1. */
963 	pte1p = kern_pte1(va);
964 	pte1_store(pte1p, PTE1_LINK(pt2_pa));
965 }
966 
967 /*
968  *  Get L2 page entry associated with given KVA.
969  *  Used in pre-bootstrap epoch.
970  */
971 static __inline pt2_entry_t*
972 pmap_preboot_vtopte2(vm_offset_t va)
973 {
974 	pt1_entry_t *pte1p;
975 
976 	/* Setup PT2 if needed. */
977 	pte1p = kern_pte1(va);
978 	if (!pte1_is_valid(pte1_load(pte1p))) /* XXX - sections ?! */
979 		pmap_preboot_pt2_setup(va);
980 
981 	return (pt2map_entry(va));
982 }
983 
984 /*
985  *  Pre-bootstrap epoch page(s) mapping(s).
986  */
987 void
988 pmap_preboot_map_pages(vm_paddr_t pa, vm_offset_t va, u_int num)
989 {
990 	u_int i;
991 	pt2_entry_t *pte2p;
992 
993 	/* Map all the pages. */
994 	for (i = 0; i < num; i++) {
995 		pte2p = pmap_preboot_vtopte2(va);
996 		pte2_store(pte2p, PTE2_KRW(pa));
997 		va += PAGE_SIZE;
998 		pa += PAGE_SIZE;
999 	}
1000 }
1001 
1002 /*
1003  *  Pre-bootstrap epoch virtual space alocator.
1004  */
1005 vm_offset_t
1006 pmap_preboot_reserve_pages(u_int num)
1007 {
1008 	u_int i;
1009 	vm_offset_t start, va;
1010 	pt2_entry_t *pte2p;
1011 
1012 	/* Allocate virtual space. */
1013 	start = va = virtual_avail;
1014 	virtual_avail += num * PAGE_SIZE;
1015 
1016 	/* Zero the mapping. */
1017 	for (i = 0; i < num; i++) {
1018 		pte2p = pmap_preboot_vtopte2(va);
1019 		pte2_store(pte2p, 0);
1020 		va += PAGE_SIZE;
1021 	}
1022 
1023 	return (start);
1024 }
1025 
1026 /*
1027  *  Pre-bootstrap epoch page(s) allocation and mapping(s).
1028  */
1029 vm_offset_t
1030 pmap_preboot_get_vpages(u_int num)
1031 {
1032 	vm_paddr_t  pa;
1033 	vm_offset_t va;
1034 
1035 	/* Allocate physical page(s). */
1036 	pa = pmap_preboot_get_pages(num);
1037 
1038 	/* Allocate virtual space. */
1039 	va = virtual_avail;
1040 	virtual_avail += num * PAGE_SIZE;
1041 
1042 	/* Map and zero all. */
1043 	pmap_preboot_map_pages(pa, va, num);
1044 	bzero((void *)va, num * PAGE_SIZE);
1045 
1046 	return (va);
1047 }
1048 
1049 /*
1050  *  Pre-bootstrap epoch page mapping(s) with attributes.
1051  */
1052 void
1053 pmap_preboot_map_attr(vm_paddr_t pa, vm_offset_t va, vm_size_t size,
1054     vm_prot_t prot, vm_memattr_t attr)
1055 {
1056 	u_int num;
1057 	u_int l1_attr, l1_prot, l2_prot, l2_attr;
1058 	pt1_entry_t *pte1p;
1059 	pt2_entry_t *pte2p;
1060 
1061 	l2_prot = prot & VM_PROT_WRITE ? PTE2_AP_KRW : PTE2_AP_KR;
1062 	l2_prot |= (prot & VM_PROT_EXECUTE) ? PTE2_X : PTE2_NX;
1063 	l2_attr = vm_memattr_to_pte2(attr);
1064 	l1_prot = ATTR_TO_L1(l2_prot);
1065 	l1_attr = ATTR_TO_L1(l2_attr);
1066 
1067 	/* Map all the pages. */
1068 	num = round_page(size);
1069 	while (num > 0) {
1070 		if ((((va | pa) & PTE1_OFFSET) == 0) && (num >= PTE1_SIZE)) {
1071 			pte1p = kern_pte1(va);
1072 			pte1_store(pte1p, PTE1_KERN(pa, l1_prot, l1_attr));
1073 			va += PTE1_SIZE;
1074 			pa += PTE1_SIZE;
1075 			num -= PTE1_SIZE;
1076 		} else {
1077 			pte2p = pmap_preboot_vtopte2(va);
1078 			pte2_store(pte2p, PTE2_KERN(pa, l2_prot, l2_attr));
1079 			va += PAGE_SIZE;
1080 			pa += PAGE_SIZE;
1081 			num -= PAGE_SIZE;
1082 		}
1083 	}
1084 }
1085 
1086 /*
1087  *  Extract from the kernel page table the physical address
1088  *  that is mapped by the given virtual address "va".
1089  */
1090 vm_paddr_t
1091 pmap_kextract(vm_offset_t va)
1092 {
1093 	vm_paddr_t pa;
1094 	pt1_entry_t pte1;
1095 	pt2_entry_t pte2;
1096 
1097 	pte1 = pte1_load(kern_pte1(va));
1098 	if (pte1_is_section(pte1)) {
1099 		pa = pte1_pa(pte1) | (va & PTE1_OFFSET);
1100 	} else if (pte1_is_link(pte1)) {
1101 		/*
1102 		 * We should beware of concurrent promotion that changes
1103 		 * pte1 at this point. However, it's not a problem as PT2
1104 		 * page is preserved by promotion in PT2TAB. So even if
1105 		 * it happens, using of PT2MAP is still safe.
1106 		 *
1107 		 * QQQ: However, concurrent removing is a problem which
1108 		 *      ends in abort on PT2MAP space. Locking must be used
1109 		 *      to deal with this.
1110 		 */
1111 		pte2 = pte2_load(pt2map_entry(va));
1112 		pa = pte2_pa(pte2) | (va & PTE2_OFFSET);
1113 	}
1114 	else {
1115 		panic("%s: va %#x pte1 %#x", __func__, va, pte1);
1116 	}
1117 	return (pa);
1118 }
1119 
1120 /*
1121  *  Extract from the kernel page table the physical address
1122  *  that is mapped by the given virtual address "va". Also
1123  *  return L2 page table entry which maps the address.
1124  *
1125  *  This is only intended to be used for panic dumps.
1126  */
1127 vm_paddr_t
1128 pmap_dump_kextract(vm_offset_t va, pt2_entry_t *pte2p)
1129 {
1130 	vm_paddr_t pa;
1131 	pt1_entry_t pte1;
1132 	pt2_entry_t pte2;
1133 
1134 	pte1 = pte1_load(kern_pte1(va));
1135 	if (pte1_is_section(pte1)) {
1136 		pa = pte1_pa(pte1) | (va & PTE1_OFFSET);
1137 		pte2 = pa | ATTR_TO_L2(pte1) | PTE2_V;
1138 	} else if (pte1_is_link(pte1)) {
1139 		pte2 = pte2_load(pt2map_entry(va));
1140 		pa = pte2_pa(pte2);
1141 	} else {
1142 		pte2 = 0;
1143 		pa = 0;
1144 	}
1145 	if (pte2p != NULL)
1146 		*pte2p = pte2;
1147 	return (pa);
1148 }
1149 
1150 /*****************************************************************************
1151  *
1152  *	PMAP second stage initialization and utility functions
1153  *	for bootstrap epoch.
1154  *
1155  *  After pmap_bootstrap() is called, the following functions for
1156  *  mappings can be used:
1157  *
1158  *  void pmap_kenter(vm_offset_t va, vm_paddr_t pa);
1159  *  void pmap_kremove(vm_offset_t va);
1160  *  vm_offset_t pmap_map(vm_offset_t *virt, vm_paddr_t start, vm_paddr_t end,
1161  *      int prot);
1162  *
1163  *  NOTE: This is not SMP coherent stage. And physical page allocation is not
1164  *        allowed during this stage.
1165  *
1166  *****************************************************************************/
1167 
1168 /*
1169  *  Initialize kernel PMAP locks and lists, kernel_pmap itself, and
1170  *  reserve various virtual spaces for temporary mappings.
1171  */
1172 void
1173 pmap_bootstrap(vm_offset_t firstaddr)
1174 {
1175 	pt2_entry_t *unused __unused;
1176 	struct pcpu *pc;
1177 
1178 	/*
1179 	 * Initialize the kernel pmap (which is statically allocated).
1180 	 */
1181 	PMAP_LOCK_INIT(kernel_pmap);
1182 	kernel_l1pa = (vm_paddr_t)kern_pt1;  /* for libkvm */
1183 	kernel_pmap->pm_pt1 = kern_pt1;
1184 	kernel_pmap->pm_pt2tab = kern_pt2tab;
1185 	CPU_FILL(&kernel_pmap->pm_active);  /* don't allow deactivation */
1186 	TAILQ_INIT(&kernel_pmap->pm_pvchunk);
1187 
1188 	/*
1189 	 * Initialize the global pv list lock.
1190 	 */
1191 	rw_init(&pvh_global_lock, "pmap pv global");
1192 
1193 	LIST_INIT(&allpmaps);
1194 
1195 	/*
1196 	 * Request a spin mutex so that changes to allpmaps cannot be
1197 	 * preempted by smp_rendezvous_cpus().
1198 	 */
1199 	mtx_init(&allpmaps_lock, "allpmaps", NULL, MTX_SPIN);
1200 	mtx_lock_spin(&allpmaps_lock);
1201 	LIST_INSERT_HEAD(&allpmaps, kernel_pmap, pm_list);
1202 	mtx_unlock_spin(&allpmaps_lock);
1203 
1204 	/*
1205 	 * Reserve some special page table entries/VA space for temporary
1206 	 * mapping of pages.
1207 	 */
1208 #define	SYSMAP(c, p, v, n)  do {		\
1209 	v = (c)pmap_preboot_reserve_pages(n);	\
1210 	p = pt2map_entry((vm_offset_t)v);	\
1211 	} while (0)
1212 
1213 	/*
1214 	 * Local CMAP1/CMAP2 are used for zeroing and copying pages.
1215 	 * Local CMAP2 is also used for data cache cleaning.
1216 	 */
1217 	pc = get_pcpu();
1218 	mtx_init(&pc->pc_cmap_lock, "SYSMAPS", NULL, MTX_DEF);
1219 	SYSMAP(caddr_t, pc->pc_cmap1_pte2p, pc->pc_cmap1_addr, 1);
1220 	SYSMAP(caddr_t, pc->pc_cmap2_pte2p, pc->pc_cmap2_addr, 1);
1221 	SYSMAP(vm_offset_t, pc->pc_qmap_pte2p, pc->pc_qmap_addr, 1);
1222 
1223 	/*
1224 	 * Crashdump maps.
1225 	 */
1226 	SYSMAP(caddr_t, unused, crashdumpmap, MAXDUMPPGS);
1227 
1228 	/*
1229 	 * _tmppt is used for reading arbitrary physical pages via /dev/mem.
1230 	 */
1231 	SYSMAP(caddr_t, unused, _tmppt, 1);
1232 
1233 	/*
1234 	 * PADDR1 and PADDR2 are used by pmap_pte2_quick() and pmap_pte2(),
1235 	 * respectively. PADDR3 is used by pmap_pte2_ddb().
1236 	 */
1237 	SYSMAP(pt2_entry_t *, PMAP1, PADDR1, 1);
1238 	SYSMAP(pt2_entry_t *, PMAP2, PADDR2, 1);
1239 #ifdef DDB
1240 	SYSMAP(pt2_entry_t *, PMAP3, PADDR3, 1);
1241 #endif
1242 	mtx_init(&PMAP2mutex, "PMAP2", NULL, MTX_DEF);
1243 
1244 	/*
1245 	 * Note that in very short time in initarm(), we are going to
1246 	 * initialize phys_avail[] array and no further page allocation
1247 	 * can happen after that until vm subsystem will be initialized.
1248 	 */
1249 	kernel_vm_end_new = kernel_vm_end;
1250 	virtual_end = vm_max_kernel_address;
1251 }
1252 
1253 static void
1254 pmap_init_reserved_pages(void)
1255 {
1256 	struct pcpu *pc;
1257 	vm_offset_t pages;
1258 	int i;
1259 
1260 	CPU_FOREACH(i) {
1261 		pc = pcpu_find(i);
1262 		/*
1263 		 * Skip if the mapping has already been initialized,
1264 		 * i.e. this is the BSP.
1265 		 */
1266 		if (pc->pc_cmap1_addr != 0)
1267 			continue;
1268 		mtx_init(&pc->pc_cmap_lock, "SYSMAPS", NULL, MTX_DEF);
1269 		pages = kva_alloc(PAGE_SIZE * 3);
1270 		if (pages == 0)
1271 			panic("%s: unable to allocate KVA", __func__);
1272 		pc->pc_cmap1_pte2p = pt2map_entry(pages);
1273 		pc->pc_cmap2_pte2p = pt2map_entry(pages + PAGE_SIZE);
1274 		pc->pc_qmap_pte2p = pt2map_entry(pages + (PAGE_SIZE * 2));
1275 		pc->pc_cmap1_addr = (caddr_t)pages;
1276 		pc->pc_cmap2_addr = (caddr_t)(pages + PAGE_SIZE);
1277 		pc->pc_qmap_addr = pages + (PAGE_SIZE * 2);
1278 	}
1279 }
1280 SYSINIT(rpages_init, SI_SUB_CPU, SI_ORDER_ANY, pmap_init_reserved_pages, NULL);
1281 
1282 /*
1283  *  The function can already be use in second initialization stage.
1284  *  As such, the function DOES NOT call pmap_growkernel() where PT2
1285  *  allocation can happen. So if used, be sure that PT2 for given
1286  *  virtual address is allocated already!
1287  *
1288  *  Add a wired page to the kva.
1289  *  Note: not SMP coherent.
1290  */
1291 static __inline void
1292 pmap_kenter_prot_attr(vm_offset_t va, vm_paddr_t pa, uint32_t prot,
1293     uint32_t attr)
1294 {
1295 	pt1_entry_t *pte1p;
1296 	pt2_entry_t *pte2p;
1297 
1298 	pte1p = kern_pte1(va);
1299 	if (!pte1_is_valid(pte1_load(pte1p))) { /* XXX - sections ?! */
1300 		/*
1301 		 * This is a very low level function, so PT2 and particularly
1302 		 * PT2PG associated with given virtual address must be already
1303 		 * allocated. It's a pain mainly during pmap initialization
1304 		 * stage. However, called after pmap initialization with
1305 		 * virtual address not under kernel_vm_end will lead to
1306 		 * the same misery.
1307 		 */
1308 		if (!pte2_is_valid(pte2_load(kern_pt2tab_entry(va))))
1309 			panic("%s: kernel PT2 not allocated!", __func__);
1310 	}
1311 
1312 	pte2p = pt2map_entry(va);
1313 	pte2_store(pte2p, PTE2_KERN(pa, prot, attr));
1314 }
1315 
1316 PMAP_INLINE void
1317 pmap_kenter(vm_offset_t va, vm_paddr_t pa)
1318 {
1319 
1320 	pmap_kenter_prot_attr(va, pa, PTE2_AP_KRW, PTE2_ATTR_DEFAULT);
1321 }
1322 
1323 /*
1324  *  Remove a page from the kernel pagetables.
1325  *  Note: not SMP coherent.
1326  */
1327 PMAP_INLINE void
1328 pmap_kremove(vm_offset_t va)
1329 {
1330 	pt1_entry_t *pte1p;
1331 	pt2_entry_t *pte2p;
1332 
1333 	pte1p = kern_pte1(va);
1334 	if (pte1_is_section(pte1_load(pte1p))) {
1335 		pte1_clear(pte1p);
1336 	} else {
1337 		pte2p = pt2map_entry(va);
1338 		pte2_clear(pte2p);
1339 	}
1340 }
1341 
1342 /*
1343  *  Share new kernel PT2PG with all pmaps.
1344  *  The caller is responsible for maintaining TLB consistency.
1345  */
1346 static void
1347 pmap_kenter_pt2tab(vm_offset_t va, pt2_entry_t npte2)
1348 {
1349 	pmap_t pmap;
1350 	pt2_entry_t *pte2p;
1351 
1352 	mtx_lock_spin(&allpmaps_lock);
1353 	LIST_FOREACH(pmap, &allpmaps, pm_list) {
1354 		pte2p = pmap_pt2tab_entry(pmap, va);
1355 		pt2tab_store(pte2p, npte2);
1356 	}
1357 	mtx_unlock_spin(&allpmaps_lock);
1358 }
1359 
1360 /*
1361  *  Share new kernel PTE1 with all pmaps.
1362  *  The caller is responsible for maintaining TLB consistency.
1363  */
1364 static void
1365 pmap_kenter_pte1(vm_offset_t va, pt1_entry_t npte1)
1366 {
1367 	pmap_t pmap;
1368 	pt1_entry_t *pte1p;
1369 
1370 	mtx_lock_spin(&allpmaps_lock);
1371 	LIST_FOREACH(pmap, &allpmaps, pm_list) {
1372 		pte1p = pmap_pte1(pmap, va);
1373 		pte1_store(pte1p, npte1);
1374 	}
1375 	mtx_unlock_spin(&allpmaps_lock);
1376 }
1377 
1378 /*
1379  *  Used to map a range of physical addresses into kernel
1380  *  virtual address space.
1381  *
1382  *  The value passed in '*virt' is a suggested virtual address for
1383  *  the mapping. Architectures which can support a direct-mapped
1384  *  physical to virtual region can return the appropriate address
1385  *  within that region, leaving '*virt' unchanged. Other
1386  *  architectures should map the pages starting at '*virt' and
1387  *  update '*virt' with the first usable address after the mapped
1388  *  region.
1389  *
1390  *  NOTE: Read the comments above pmap_kenter_prot_attr() as
1391  *        the function is used herein!
1392  */
1393 vm_offset_t
1394 pmap_map(vm_offset_t *virt, vm_paddr_t start, vm_paddr_t end, int prot)
1395 {
1396 	vm_offset_t va, sva;
1397 	vm_paddr_t pte1_offset;
1398 	pt1_entry_t npte1;
1399 	uint32_t l1prot, l2prot;
1400 	uint32_t l1attr, l2attr;
1401 
1402 	PDEBUG(1, printf("%s: virt = %#x, start = %#x, end = %#x (size = %#x),"
1403 	    " prot = %d\n", __func__, *virt, start, end, end - start,  prot));
1404 
1405 	l2prot = (prot & VM_PROT_WRITE) ? PTE2_AP_KRW : PTE2_AP_KR;
1406 	l2prot |= (prot & VM_PROT_EXECUTE) ? PTE2_X : PTE2_NX;
1407 	l1prot = ATTR_TO_L1(l2prot);
1408 
1409 	l2attr = PTE2_ATTR_DEFAULT;
1410 	l1attr = ATTR_TO_L1(l2attr);
1411 
1412 	va = *virt;
1413 	/*
1414 	 * Does the physical address range's size and alignment permit at
1415 	 * least one section mapping to be created?
1416 	 */
1417 	pte1_offset = start & PTE1_OFFSET;
1418 	if ((end - start) - ((PTE1_SIZE - pte1_offset) & PTE1_OFFSET) >=
1419 	    PTE1_SIZE) {
1420 		/*
1421 		 * Increase the starting virtual address so that its alignment
1422 		 * does not preclude the use of section mappings.
1423 		 */
1424 		if ((va & PTE1_OFFSET) < pte1_offset)
1425 			va = pte1_trunc(va) + pte1_offset;
1426 		else if ((va & PTE1_OFFSET) > pte1_offset)
1427 			va = pte1_roundup(va) + pte1_offset;
1428 	}
1429 	sva = va;
1430 	while (start < end) {
1431 		if ((start & PTE1_OFFSET) == 0 && end - start >= PTE1_SIZE) {
1432 			KASSERT((va & PTE1_OFFSET) == 0,
1433 			    ("%s: misaligned va %#x", __func__, va));
1434 			npte1 = PTE1_KERN(start, l1prot, l1attr);
1435 			pmap_kenter_pte1(va, npte1);
1436 			va += PTE1_SIZE;
1437 			start += PTE1_SIZE;
1438 		} else {
1439 			pmap_kenter_prot_attr(va, start, l2prot, l2attr);
1440 			va += PAGE_SIZE;
1441 			start += PAGE_SIZE;
1442 		}
1443 	}
1444 	tlb_flush_range(sva, va - sva);
1445 	*virt = va;
1446 	return (sva);
1447 }
1448 
1449 /*
1450  *  Make a temporary mapping for a physical address.
1451  *  This is only intended to be used for panic dumps.
1452  */
1453 void *
1454 pmap_kenter_temporary(vm_paddr_t pa, int i)
1455 {
1456 	vm_offset_t va;
1457 
1458 	/* QQQ: 'i' should be less or equal to MAXDUMPPGS. */
1459 
1460 	va = (vm_offset_t)crashdumpmap + (i * PAGE_SIZE);
1461 	pmap_kenter(va, pa);
1462 	tlb_flush_local(va);
1463 	return ((void *)crashdumpmap);
1464 }
1465 
1466 
1467 /*************************************
1468  *
1469  *  TLB & cache maintenance routines.
1470  *
1471  *************************************/
1472 
1473 /*
1474  *  We inline these within pmap.c for speed.
1475  */
1476 PMAP_INLINE void
1477 pmap_tlb_flush(pmap_t pmap, vm_offset_t va)
1478 {
1479 
1480 	if (pmap == kernel_pmap || !CPU_EMPTY(&pmap->pm_active))
1481 		tlb_flush(va);
1482 }
1483 
1484 PMAP_INLINE void
1485 pmap_tlb_flush_range(pmap_t pmap, vm_offset_t sva, vm_size_t size)
1486 {
1487 
1488 	if (pmap == kernel_pmap || !CPU_EMPTY(&pmap->pm_active))
1489 		tlb_flush_range(sva, size);
1490 }
1491 
1492 /*
1493  *  Abuse the pte2 nodes for unmapped kva to thread a kva freelist through.
1494  *  Requirements:
1495  *   - Must deal with pages in order to ensure that none of the PTE2_* bits
1496  *     are ever set, PTE2_V in particular.
1497  *   - Assumes we can write to pte2s without pte2_store() atomic ops.
1498  *   - Assumes nothing will ever test these addresses for 0 to indicate
1499  *     no mapping instead of correctly checking PTE2_V.
1500  *   - Assumes a vm_offset_t will fit in a pte2 (true for arm).
1501  *  Because PTE2_V is never set, there can be no mappings to invalidate.
1502  */
1503 static vm_offset_t
1504 pmap_pte2list_alloc(vm_offset_t *head)
1505 {
1506 	pt2_entry_t *pte2p;
1507 	vm_offset_t va;
1508 
1509 	va = *head;
1510 	if (va == 0)
1511 		panic("pmap_ptelist_alloc: exhausted ptelist KVA");
1512 	pte2p = pt2map_entry(va);
1513 	*head = *pte2p;
1514 	if (*head & PTE2_V)
1515 		panic("%s: va with PTE2_V set!", __func__);
1516 	*pte2p = 0;
1517 	return (va);
1518 }
1519 
1520 static void
1521 pmap_pte2list_free(vm_offset_t *head, vm_offset_t va)
1522 {
1523 	pt2_entry_t *pte2p;
1524 
1525 	if (va & PTE2_V)
1526 		panic("%s: freeing va with PTE2_V set!", __func__);
1527 	pte2p = pt2map_entry(va);
1528 	*pte2p = *head;		/* virtual! PTE2_V is 0 though */
1529 	*head = va;
1530 }
1531 
1532 static void
1533 pmap_pte2list_init(vm_offset_t *head, void *base, int npages)
1534 {
1535 	int i;
1536 	vm_offset_t va;
1537 
1538 	*head = 0;
1539 	for (i = npages - 1; i >= 0; i--) {
1540 		va = (vm_offset_t)base + i * PAGE_SIZE;
1541 		pmap_pte2list_free(head, va);
1542 	}
1543 }
1544 
1545 /*****************************************************************************
1546  *
1547  *	PMAP third and final stage initialization.
1548  *
1549  *  After pmap_init() is called, PMAP subsystem is fully initialized.
1550  *
1551  *****************************************************************************/
1552 
1553 SYSCTL_NODE(_vm, OID_AUTO, pmap, CTLFLAG_RD, 0, "VM/pmap parameters");
1554 
1555 SYSCTL_INT(_vm_pmap, OID_AUTO, pv_entry_max, CTLFLAG_RD, &pv_entry_max, 0,
1556     "Max number of PV entries");
1557 SYSCTL_INT(_vm_pmap, OID_AUTO, shpgperproc, CTLFLAG_RD, &shpgperproc, 0,
1558     "Page share factor per proc");
1559 
1560 static u_long nkpt2pg = NKPT2PG;
1561 SYSCTL_ULONG(_vm_pmap, OID_AUTO, nkpt2pg, CTLFLAG_RD,
1562     &nkpt2pg, 0, "Pre-allocated pages for kernel PT2s");
1563 
1564 static int sp_enabled = 1;
1565 SYSCTL_INT(_vm_pmap, OID_AUTO, sp_enabled, CTLFLAG_RDTUN | CTLFLAG_NOFETCH,
1566     &sp_enabled, 0, "Are large page mappings enabled?");
1567 
1568 bool
1569 pmap_ps_enabled(pmap_t pmap __unused)
1570 {
1571 
1572 	return (sp_enabled != 0);
1573 }
1574 
1575 static SYSCTL_NODE(_vm_pmap, OID_AUTO, pte1, CTLFLAG_RD, 0,
1576     "1MB page mapping counters");
1577 
1578 static u_long pmap_pte1_demotions;
1579 SYSCTL_ULONG(_vm_pmap_pte1, OID_AUTO, demotions, CTLFLAG_RD,
1580     &pmap_pte1_demotions, 0, "1MB page demotions");
1581 
1582 static u_long pmap_pte1_mappings;
1583 SYSCTL_ULONG(_vm_pmap_pte1, OID_AUTO, mappings, CTLFLAG_RD,
1584     &pmap_pte1_mappings, 0, "1MB page mappings");
1585 
1586 static u_long pmap_pte1_p_failures;
1587 SYSCTL_ULONG(_vm_pmap_pte1, OID_AUTO, p_failures, CTLFLAG_RD,
1588     &pmap_pte1_p_failures, 0, "1MB page promotion failures");
1589 
1590 static u_long pmap_pte1_promotions;
1591 SYSCTL_ULONG(_vm_pmap_pte1, OID_AUTO, promotions, CTLFLAG_RD,
1592     &pmap_pte1_promotions, 0, "1MB page promotions");
1593 
1594 static u_long pmap_pte1_kern_demotions;
1595 SYSCTL_ULONG(_vm_pmap_pte1, OID_AUTO, kern_demotions, CTLFLAG_RD,
1596     &pmap_pte1_kern_demotions, 0, "1MB page kernel demotions");
1597 
1598 static u_long pmap_pte1_kern_promotions;
1599 SYSCTL_ULONG(_vm_pmap_pte1, OID_AUTO, kern_promotions, CTLFLAG_RD,
1600     &pmap_pte1_kern_promotions, 0, "1MB page kernel promotions");
1601 
1602 static __inline ttb_entry_t
1603 pmap_ttb_get(pmap_t pmap)
1604 {
1605 
1606 	return (vtophys(pmap->pm_pt1) | ttb_flags);
1607 }
1608 
1609 /*
1610  *  Initialize a vm_page's machine-dependent fields.
1611  *
1612  *  Variations:
1613  *  1. Pages for L2 page tables are always not managed. So, pv_list and
1614  *     pt2_wirecount can share same physical space. However, proper
1615  *     initialization on a page alloc for page tables and reinitialization
1616  *     on the page free must be ensured.
1617  */
1618 void
1619 pmap_page_init(vm_page_t m)
1620 {
1621 
1622 	TAILQ_INIT(&m->md.pv_list);
1623 	pt2_wirecount_init(m);
1624 	m->md.pat_mode = VM_MEMATTR_DEFAULT;
1625 }
1626 
1627 /*
1628  *  Virtualization for faster way how to zero whole page.
1629  */
1630 static __inline void
1631 pagezero(void *page)
1632 {
1633 
1634 	bzero(page, PAGE_SIZE);
1635 }
1636 
1637 /*
1638  *  Zero L2 page table page.
1639  *  Use same KVA as in pmap_zero_page().
1640  */
1641 static __inline vm_paddr_t
1642 pmap_pt2pg_zero(vm_page_t m)
1643 {
1644 	pt2_entry_t *cmap2_pte2p;
1645 	vm_paddr_t pa;
1646 	struct pcpu *pc;
1647 
1648 	pa = VM_PAGE_TO_PHYS(m);
1649 
1650 	/*
1651 	 * XXX: For now, we map whole page even if it's already zero,
1652 	 *      to sync it even if the sync is only DSB.
1653 	 */
1654 	sched_pin();
1655 	pc = get_pcpu();
1656 	cmap2_pte2p = pc->pc_cmap2_pte2p;
1657 	mtx_lock(&pc->pc_cmap_lock);
1658 	if (pte2_load(cmap2_pte2p) != 0)
1659 		panic("%s: CMAP2 busy", __func__);
1660 	pte2_store(cmap2_pte2p, PTE2_KERN_NG(pa, PTE2_AP_KRW,
1661 	    vm_page_pte2_attr(m)));
1662 	/*  Even VM_ALLOC_ZERO request is only advisory. */
1663 	if ((m->flags & PG_ZERO) == 0)
1664 		pagezero(pc->pc_cmap2_addr);
1665 	pte2_sync_range((pt2_entry_t *)pc->pc_cmap2_addr, PAGE_SIZE);
1666 	pte2_clear(cmap2_pte2p);
1667 	tlb_flush((vm_offset_t)pc->pc_cmap2_addr);
1668 
1669 	/*
1670 	 * Unpin the thread before releasing the lock.  Otherwise the thread
1671 	 * could be rescheduled while still bound to the current CPU, only
1672 	 * to unpin itself immediately upon resuming execution.
1673 	 */
1674 	sched_unpin();
1675 	mtx_unlock(&pc->pc_cmap_lock);
1676 
1677 	return (pa);
1678 }
1679 
1680 /*
1681  *  Init just allocated page as L2 page table(s) holder
1682  *  and return its physical address.
1683  */
1684 static __inline vm_paddr_t
1685 pmap_pt2pg_init(pmap_t pmap, vm_offset_t va, vm_page_t m)
1686 {
1687 	vm_paddr_t pa;
1688 	pt2_entry_t *pte2p;
1689 
1690 	/* Check page attributes. */
1691 	if (m->md.pat_mode != pt_memattr)
1692 		pmap_page_set_memattr(m, pt_memattr);
1693 
1694 	/* Zero page and init wire counts. */
1695 	pa = pmap_pt2pg_zero(m);
1696 	pt2_wirecount_init(m);
1697 
1698 	/*
1699 	 * Map page to PT2MAP address space for given pmap.
1700 	 * Note that PT2MAP space is shared with all pmaps.
1701 	 */
1702 	if (pmap == kernel_pmap)
1703 		pmap_kenter_pt2tab(va, PTE2_KPT(pa));
1704 	else {
1705 		pte2p = pmap_pt2tab_entry(pmap, va);
1706 		pt2tab_store(pte2p, PTE2_KPT_NG(pa));
1707 	}
1708 
1709 	return (pa);
1710 }
1711 
1712 /*
1713  *  Initialize the pmap module.
1714  *  Called by vm_init, to initialize any structures that the pmap
1715  *  system needs to map virtual memory.
1716  */
1717 void
1718 pmap_init(void)
1719 {
1720 	vm_size_t s;
1721 	pt2_entry_t *pte2p, pte2;
1722 	u_int i, pte1_idx, pv_npg;
1723 
1724 	PDEBUG(1, printf("%s: phys_start = %#x\n", __func__, PHYSADDR));
1725 
1726 	/*
1727 	 * Initialize the vm page array entries for kernel pmap's
1728 	 * L2 page table pages allocated in advance.
1729 	 */
1730 	pte1_idx = pte1_index(KERNBASE - PT2MAP_SIZE);
1731 	pte2p = kern_pt2tab_entry(KERNBASE - PT2MAP_SIZE);
1732 	for (i = 0; i < nkpt2pg + NPG_IN_PT2TAB; i++, pte2p++) {
1733 		vm_paddr_t pa;
1734 		vm_page_t m;
1735 
1736 		pte2 = pte2_load(pte2p);
1737 		KASSERT(pte2_is_valid(pte2), ("%s: no valid entry", __func__));
1738 
1739 		pa = pte2_pa(pte2);
1740 		m = PHYS_TO_VM_PAGE(pa);
1741 		KASSERT(m >= vm_page_array &&
1742 		    m < &vm_page_array[vm_page_array_size],
1743 		    ("%s: L2 page table page is out of range", __func__));
1744 
1745 		m->pindex = pte1_idx;
1746 		m->phys_addr = pa;
1747 		pte1_idx += NPT2_IN_PG;
1748 	}
1749 
1750 	/*
1751 	 * Initialize the address space (zone) for the pv entries.  Set a
1752 	 * high water mark so that the system can recover from excessive
1753 	 * numbers of pv entries.
1754 	 */
1755 	TUNABLE_INT_FETCH("vm.pmap.shpgperproc", &shpgperproc);
1756 	pv_entry_max = shpgperproc * maxproc + vm_cnt.v_page_count;
1757 	TUNABLE_INT_FETCH("vm.pmap.pv_entries", &pv_entry_max);
1758 	pv_entry_max = roundup(pv_entry_max, _NPCPV);
1759 	pv_entry_high_water = 9 * (pv_entry_max / 10);
1760 
1761 	/*
1762 	 * Are large page mappings enabled?
1763 	 */
1764 	TUNABLE_INT_FETCH("vm.pmap.sp_enabled", &sp_enabled);
1765 	if (sp_enabled) {
1766 		KASSERT(MAXPAGESIZES > 1 && pagesizes[1] == 0,
1767 		    ("%s: can't assign to pagesizes[1]", __func__));
1768 		pagesizes[1] = PTE1_SIZE;
1769 	}
1770 
1771 	/*
1772 	 * Calculate the size of the pv head table for sections.
1773 	 * Handle the possibility that "vm_phys_segs[...].end" is zero.
1774 	 * Note that the table is only for sections which could be promoted.
1775 	 */
1776 	first_managed_pa = pte1_trunc(vm_phys_segs[0].start);
1777 	pv_npg = (pte1_trunc(vm_phys_segs[vm_phys_nsegs - 1].end - PAGE_SIZE)
1778 	    - first_managed_pa) / PTE1_SIZE + 1;
1779 
1780 	/*
1781 	 * Allocate memory for the pv head table for sections.
1782 	 */
1783 	s = (vm_size_t)(pv_npg * sizeof(struct md_page));
1784 	s = round_page(s);
1785 	pv_table = (struct md_page *)kmem_malloc(s, M_WAITOK | M_ZERO);
1786 	for (i = 0; i < pv_npg; i++)
1787 		TAILQ_INIT(&pv_table[i].pv_list);
1788 
1789 	pv_maxchunks = MAX(pv_entry_max / _NPCPV, maxproc);
1790 	pv_chunkbase = (struct pv_chunk *)kva_alloc(PAGE_SIZE * pv_maxchunks);
1791 	if (pv_chunkbase == NULL)
1792 		panic("%s: not enough kvm for pv chunks", __func__);
1793 	pmap_pte2list_init(&pv_vafree, pv_chunkbase, pv_maxchunks);
1794 }
1795 
1796 /*
1797  *  Add a list of wired pages to the kva
1798  *  this routine is only used for temporary
1799  *  kernel mappings that do not need to have
1800  *  page modification or references recorded.
1801  *  Note that old mappings are simply written
1802  *  over.  The page *must* be wired.
1803  *  Note: SMP coherent.  Uses a ranged shootdown IPI.
1804  */
1805 void
1806 pmap_qenter(vm_offset_t sva, vm_page_t *ma, int count)
1807 {
1808 	u_int anychanged;
1809 	pt2_entry_t *epte2p, *pte2p, pte2;
1810 	vm_page_t m;
1811 	vm_paddr_t pa;
1812 
1813 	anychanged = 0;
1814 	pte2p = pt2map_entry(sva);
1815 	epte2p = pte2p + count;
1816 	while (pte2p < epte2p) {
1817 		m = *ma++;
1818 		pa = VM_PAGE_TO_PHYS(m);
1819 		pte2 = pte2_load(pte2p);
1820 		if ((pte2_pa(pte2) != pa) ||
1821 		    (pte2_attr(pte2) != vm_page_pte2_attr(m))) {
1822 			anychanged++;
1823 			pte2_store(pte2p, PTE2_KERN(pa, PTE2_AP_KRW,
1824 			    vm_page_pte2_attr(m)));
1825 		}
1826 		pte2p++;
1827 	}
1828 	if (__predict_false(anychanged))
1829 		tlb_flush_range(sva, count * PAGE_SIZE);
1830 }
1831 
1832 /*
1833  *  This routine tears out page mappings from the
1834  *  kernel -- it is meant only for temporary mappings.
1835  *  Note: SMP coherent.  Uses a ranged shootdown IPI.
1836  */
1837 void
1838 pmap_qremove(vm_offset_t sva, int count)
1839 {
1840 	vm_offset_t va;
1841 
1842 	va = sva;
1843 	while (count-- > 0) {
1844 		pmap_kremove(va);
1845 		va += PAGE_SIZE;
1846 	}
1847 	tlb_flush_range(sva, va - sva);
1848 }
1849 
1850 /*
1851  *  Are we current address space or kernel?
1852  */
1853 static __inline int
1854 pmap_is_current(pmap_t pmap)
1855 {
1856 
1857 	return (pmap == kernel_pmap ||
1858 		(pmap == vmspace_pmap(curthread->td_proc->p_vmspace)));
1859 }
1860 
1861 /*
1862  *  If the given pmap is not the current or kernel pmap, the returned
1863  *  pte2 must be released by passing it to pmap_pte2_release().
1864  */
1865 static pt2_entry_t *
1866 pmap_pte2(pmap_t pmap, vm_offset_t va)
1867 {
1868 	pt1_entry_t pte1;
1869 	vm_paddr_t pt2pg_pa;
1870 
1871 	pte1 = pte1_load(pmap_pte1(pmap, va));
1872 	if (pte1_is_section(pte1))
1873 		panic("%s: attempt to map PTE1", __func__);
1874 	if (pte1_is_link(pte1)) {
1875 		/* Are we current address space or kernel? */
1876 		if (pmap_is_current(pmap))
1877 			return (pt2map_entry(va));
1878 		/* Note that L2 page table size is not equal to PAGE_SIZE. */
1879 		pt2pg_pa = trunc_page(pte1_link_pa(pte1));
1880 		mtx_lock(&PMAP2mutex);
1881 		if (pte2_pa(pte2_load(PMAP2)) != pt2pg_pa) {
1882 			pte2_store(PMAP2, PTE2_KPT(pt2pg_pa));
1883 			tlb_flush((vm_offset_t)PADDR2);
1884 		}
1885 		return (PADDR2 + (arm32_btop(va) & (NPTE2_IN_PG - 1)));
1886 	}
1887 	return (NULL);
1888 }
1889 
1890 /*
1891  *  Releases a pte2 that was obtained from pmap_pte2().
1892  *  Be prepared for the pte2p being NULL.
1893  */
1894 static __inline void
1895 pmap_pte2_release(pt2_entry_t *pte2p)
1896 {
1897 
1898 	if ((pt2_entry_t *)(trunc_page((vm_offset_t)pte2p)) == PADDR2) {
1899 		mtx_unlock(&PMAP2mutex);
1900 	}
1901 }
1902 
1903 /*
1904  *  Super fast pmap_pte2 routine best used when scanning
1905  *  the pv lists.  This eliminates many coarse-grained
1906  *  invltlb calls.  Note that many of the pv list
1907  *  scans are across different pmaps.  It is very wasteful
1908  *  to do an entire tlb flush for checking a single mapping.
1909  *
1910  *  If the given pmap is not the current pmap, pvh_global_lock
1911  *  must be held and curthread pinned to a CPU.
1912  */
1913 static pt2_entry_t *
1914 pmap_pte2_quick(pmap_t pmap, vm_offset_t va)
1915 {
1916 	pt1_entry_t pte1;
1917 	vm_paddr_t pt2pg_pa;
1918 
1919 	pte1 = pte1_load(pmap_pte1(pmap, va));
1920 	if (pte1_is_section(pte1))
1921 		panic("%s: attempt to map PTE1", __func__);
1922 	if (pte1_is_link(pte1)) {
1923 		/* Are we current address space or kernel? */
1924 		if (pmap_is_current(pmap))
1925 			return (pt2map_entry(va));
1926 		rw_assert(&pvh_global_lock, RA_WLOCKED);
1927 		KASSERT(curthread->td_pinned > 0,
1928 		    ("%s: curthread not pinned", __func__));
1929 		/* Note that L2 page table size is not equal to PAGE_SIZE. */
1930 		pt2pg_pa = trunc_page(pte1_link_pa(pte1));
1931 		if (pte2_pa(pte2_load(PMAP1)) != pt2pg_pa) {
1932 			pte2_store(PMAP1, PTE2_KPT(pt2pg_pa));
1933 #ifdef SMP
1934 			PMAP1cpu = PCPU_GET(cpuid);
1935 #endif
1936 			tlb_flush_local((vm_offset_t)PADDR1);
1937 			PMAP1changed++;
1938 		} else
1939 #ifdef SMP
1940 		if (PMAP1cpu != PCPU_GET(cpuid)) {
1941 			PMAP1cpu = PCPU_GET(cpuid);
1942 			tlb_flush_local((vm_offset_t)PADDR1);
1943 			PMAP1changedcpu++;
1944 		} else
1945 #endif
1946 			PMAP1unchanged++;
1947 		return (PADDR1 + (arm32_btop(va) & (NPTE2_IN_PG - 1)));
1948 	}
1949 	return (NULL);
1950 }
1951 
1952 /*
1953  *  Routine: pmap_extract
1954  *  Function:
1955  * 	Extract the physical page address associated
1956  *	with the given map/virtual_address pair.
1957  */
1958 vm_paddr_t
1959 pmap_extract(pmap_t pmap, vm_offset_t va)
1960 {
1961 	vm_paddr_t pa;
1962 	pt1_entry_t pte1;
1963 	pt2_entry_t *pte2p;
1964 
1965 	PMAP_LOCK(pmap);
1966 	pte1 = pte1_load(pmap_pte1(pmap, va));
1967 	if (pte1_is_section(pte1))
1968 		pa = pte1_pa(pte1) | (va & PTE1_OFFSET);
1969 	else if (pte1_is_link(pte1)) {
1970 		pte2p = pmap_pte2(pmap, va);
1971 		pa = pte2_pa(pte2_load(pte2p)) | (va & PTE2_OFFSET);
1972 		pmap_pte2_release(pte2p);
1973 	} else
1974 		pa = 0;
1975 	PMAP_UNLOCK(pmap);
1976 	return (pa);
1977 }
1978 
1979 /*
1980  *  Routine: pmap_extract_and_hold
1981  *  Function:
1982  *	Atomically extract and hold the physical page
1983  *	with the given pmap and virtual address pair
1984  *	if that mapping permits the given protection.
1985  */
1986 vm_page_t
1987 pmap_extract_and_hold(pmap_t pmap, vm_offset_t va, vm_prot_t prot)
1988 {
1989 	vm_paddr_t pa, lockpa;
1990 	pt1_entry_t pte1;
1991 	pt2_entry_t pte2, *pte2p;
1992 	vm_page_t m;
1993 
1994 	lockpa = 0;
1995 	m = NULL;
1996 	PMAP_LOCK(pmap);
1997 retry:
1998 	pte1 = pte1_load(pmap_pte1(pmap, va));
1999 	if (pte1_is_section(pte1)) {
2000 		if (!(pte1 & PTE1_RO) || !(prot & VM_PROT_WRITE)) {
2001 			pa = pte1_pa(pte1) | (va & PTE1_OFFSET);
2002 			if (vm_page_pa_tryrelock(pmap, pa, &lockpa))
2003 				goto retry;
2004 			m = PHYS_TO_VM_PAGE(pa);
2005 			vm_page_hold(m);
2006 		}
2007 	} else if (pte1_is_link(pte1)) {
2008 		pte2p = pmap_pte2(pmap, va);
2009 		pte2 = pte2_load(pte2p);
2010 		pmap_pte2_release(pte2p);
2011 		if (pte2_is_valid(pte2) &&
2012 		    (!(pte2 & PTE2_RO) || !(prot & VM_PROT_WRITE))) {
2013 			pa = pte2_pa(pte2);
2014 			if (vm_page_pa_tryrelock(pmap, pa, &lockpa))
2015 				goto retry;
2016 			m = PHYS_TO_VM_PAGE(pa);
2017 			vm_page_hold(m);
2018 		}
2019 	}
2020 	PA_UNLOCK_COND(lockpa);
2021 	PMAP_UNLOCK(pmap);
2022 	return (m);
2023 }
2024 
2025 /*
2026  *  Grow the number of kernel L2 page table entries, if needed.
2027  */
2028 void
2029 pmap_growkernel(vm_offset_t addr)
2030 {
2031 	vm_page_t m;
2032 	vm_paddr_t pt2pg_pa, pt2_pa;
2033 	pt1_entry_t pte1;
2034 	pt2_entry_t pte2;
2035 
2036 	PDEBUG(1, printf("%s: addr = %#x\n", __func__, addr));
2037 	/*
2038 	 * All the time kernel_vm_end is first KVA for which underlying
2039 	 * L2 page table is either not allocated or linked from L1 page table
2040 	 * (not considering sections). Except for two possible cases:
2041 	 *
2042 	 *   (1) in the very beginning as long as pmap_growkernel() was
2043 	 *       not called, it could be first unused KVA (which is not
2044 	 *       rounded up to PTE1_SIZE),
2045 	 *
2046 	 *   (2) when all KVA space is mapped and vm_map_max(kernel_map)
2047 	 *       address is not rounded up to PTE1_SIZE. (For example,
2048 	 *       it could be 0xFFFFFFFF.)
2049 	 */
2050 	kernel_vm_end = pte1_roundup(kernel_vm_end);
2051 	mtx_assert(&kernel_map->system_mtx, MA_OWNED);
2052 	addr = roundup2(addr, PTE1_SIZE);
2053 	if (addr - 1 >= vm_map_max(kernel_map))
2054 		addr = vm_map_max(kernel_map);
2055 	while (kernel_vm_end < addr) {
2056 		pte1 = pte1_load(kern_pte1(kernel_vm_end));
2057 		if (pte1_is_valid(pte1)) {
2058 			kernel_vm_end += PTE1_SIZE;
2059 			if (kernel_vm_end - 1 >= vm_map_max(kernel_map)) {
2060 				kernel_vm_end = vm_map_max(kernel_map);
2061 				break;
2062 			}
2063 			continue;
2064 		}
2065 
2066 		/*
2067 		 * kernel_vm_end_new is used in pmap_pinit() when kernel
2068 		 * mappings are entered to new pmap all at once to avoid race
2069 		 * between pmap_kenter_pte1() and kernel_vm_end increase.
2070 		 * The same aplies to pmap_kenter_pt2tab().
2071 		 */
2072 		kernel_vm_end_new = kernel_vm_end + PTE1_SIZE;
2073 
2074 		pte2 = pt2tab_load(kern_pt2tab_entry(kernel_vm_end));
2075 		if (!pte2_is_valid(pte2)) {
2076 			/*
2077 			 * Install new PT2s page into kernel PT2TAB.
2078 			 */
2079 			m = vm_page_alloc(NULL,
2080 			    pte1_index(kernel_vm_end) & ~PT2PG_MASK,
2081 			    VM_ALLOC_INTERRUPT | VM_ALLOC_NOOBJ |
2082 			    VM_ALLOC_WIRED | VM_ALLOC_ZERO);
2083 			if (m == NULL)
2084 				panic("%s: no memory to grow kernel", __func__);
2085 			/*
2086 			 * QQQ: To link all new L2 page tables from L1 page
2087 			 *      table now and so pmap_kenter_pte1() them
2088 			 *      at once together with pmap_kenter_pt2tab()
2089 			 *      could be nice speed up. However,
2090 			 *      pmap_growkernel() does not happen so often...
2091 			 * QQQ: The other TTBR is another option.
2092 			 */
2093 			pt2pg_pa = pmap_pt2pg_init(kernel_pmap, kernel_vm_end,
2094 			    m);
2095 		} else
2096 			pt2pg_pa = pte2_pa(pte2);
2097 
2098 		pt2_pa = page_pt2pa(pt2pg_pa, pte1_index(kernel_vm_end));
2099 		pmap_kenter_pte1(kernel_vm_end, PTE1_LINK(pt2_pa));
2100 
2101 		kernel_vm_end = kernel_vm_end_new;
2102 		if (kernel_vm_end - 1 >= vm_map_max(kernel_map)) {
2103 			kernel_vm_end = vm_map_max(kernel_map);
2104 			break;
2105 		}
2106 	}
2107 }
2108 
2109 static int
2110 kvm_size(SYSCTL_HANDLER_ARGS)
2111 {
2112 	unsigned long ksize = vm_max_kernel_address - KERNBASE;
2113 
2114 	return (sysctl_handle_long(oidp, &ksize, 0, req));
2115 }
2116 SYSCTL_PROC(_vm, OID_AUTO, kvm_size, CTLTYPE_LONG|CTLFLAG_RD,
2117     0, 0, kvm_size, "IU", "Size of KVM");
2118 
2119 static int
2120 kvm_free(SYSCTL_HANDLER_ARGS)
2121 {
2122 	unsigned long kfree = vm_max_kernel_address - kernel_vm_end;
2123 
2124 	return (sysctl_handle_long(oidp, &kfree, 0, req));
2125 }
2126 SYSCTL_PROC(_vm, OID_AUTO, kvm_free, CTLTYPE_LONG|CTLFLAG_RD,
2127     0, 0, kvm_free, "IU", "Amount of KVM free");
2128 
2129 /***********************************************
2130  *
2131  *  Pmap allocation/deallocation routines.
2132  *
2133  ***********************************************/
2134 
2135 /*
2136  *  Initialize the pmap for the swapper process.
2137  */
2138 void
2139 pmap_pinit0(pmap_t pmap)
2140 {
2141 	PDEBUG(1, printf("%s: pmap = %p\n", __func__, pmap));
2142 
2143 	PMAP_LOCK_INIT(pmap);
2144 
2145 	/*
2146 	 * Kernel page table directory and pmap stuff around is already
2147 	 * initialized, we are using it right now and here. So, finish
2148 	 * only PMAP structures initialization for process0 ...
2149 	 *
2150 	 * Since the L1 page table and PT2TAB is shared with the kernel pmap,
2151 	 * which is already included in the list "allpmaps", this pmap does
2152 	 * not need to be inserted into that list.
2153 	 */
2154 	pmap->pm_pt1 = kern_pt1;
2155 	pmap->pm_pt2tab = kern_pt2tab;
2156 	CPU_ZERO(&pmap->pm_active);
2157 	PCPU_SET(curpmap, pmap);
2158 	TAILQ_INIT(&pmap->pm_pvchunk);
2159 	bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
2160 	CPU_SET(0, &pmap->pm_active);
2161 }
2162 
2163 static __inline void
2164 pte1_copy_nosync(pt1_entry_t *spte1p, pt1_entry_t *dpte1p, vm_offset_t sva,
2165     vm_offset_t eva)
2166 {
2167 	u_int idx, count;
2168 
2169 	idx = pte1_index(sva);
2170 	count = (pte1_index(eva) - idx + 1) * sizeof(pt1_entry_t);
2171 	bcopy(spte1p + idx, dpte1p + idx, count);
2172 }
2173 
2174 static __inline void
2175 pt2tab_copy_nosync(pt2_entry_t *spte2p, pt2_entry_t *dpte2p, vm_offset_t sva,
2176     vm_offset_t eva)
2177 {
2178 	u_int idx, count;
2179 
2180 	idx = pt2tab_index(sva);
2181 	count = (pt2tab_index(eva) - idx + 1) * sizeof(pt2_entry_t);
2182 	bcopy(spte2p + idx, dpte2p + idx, count);
2183 }
2184 
2185 /*
2186  *  Initialize a preallocated and zeroed pmap structure,
2187  *  such as one in a vmspace structure.
2188  */
2189 int
2190 pmap_pinit(pmap_t pmap)
2191 {
2192 	pt1_entry_t *pte1p;
2193 	pt2_entry_t *pte2p;
2194 	vm_paddr_t pa, pt2tab_pa;
2195 	u_int i;
2196 
2197 	PDEBUG(6, printf("%s: pmap = %p, pm_pt1 = %p\n", __func__, pmap,
2198 	    pmap->pm_pt1));
2199 
2200 	/*
2201 	 * No need to allocate L2 page table space yet but we do need
2202 	 * a valid L1 page table and PT2TAB table.
2203 	 *
2204 	 * Install shared kernel mappings to these tables. It's a little
2205 	 * tricky as some parts of KVA are reserved for vectors, devices,
2206 	 * and whatever else. These parts are supposed to be above
2207 	 * vm_max_kernel_address. Thus two regions should be installed:
2208 	 *
2209 	 *   (1) <KERNBASE, kernel_vm_end),
2210 	 *   (2) <vm_max_kernel_address, 0xFFFFFFFF>.
2211 	 *
2212 	 * QQQ: The second region should be stable enough to be installed
2213 	 *      only once in time when the tables are allocated.
2214 	 * QQQ: Maybe copy of both regions at once could be faster ...
2215 	 * QQQ: Maybe the other TTBR is an option.
2216 	 *
2217 	 * Finally, install own PT2TAB table to these tables.
2218 	 */
2219 
2220 	if (pmap->pm_pt1 == NULL) {
2221 		pmap->pm_pt1 = (pt1_entry_t *)kmem_alloc_contig(NB_IN_PT1,
2222 		    M_NOWAIT | M_ZERO, 0, -1UL, NB_IN_PT1, 0, pt_memattr);
2223 		if (pmap->pm_pt1 == NULL)
2224 			return (0);
2225 	}
2226 	if (pmap->pm_pt2tab == NULL) {
2227 		/*
2228 		 * QQQ: (1) PT2TAB must be contiguous. If PT2TAB is one page
2229 		 *      only, what should be the only size for 32 bit systems,
2230 		 *      then we could allocate it with vm_page_alloc() and all
2231 		 *      the stuff needed as other L2 page table pages.
2232 		 *      (2) Note that a process PT2TAB is special L2 page table
2233 		 *      page. Its mapping in kernel_arena is permanent and can
2234 		 *      be used no matter which process is current. Its mapping
2235 		 *      in PT2MAP can be used only for current process.
2236 		 */
2237 		pmap->pm_pt2tab = (pt2_entry_t *)kmem_alloc_attr(NB_IN_PT2TAB,
2238 		    M_NOWAIT | M_ZERO, 0, -1UL, pt_memattr);
2239 		if (pmap->pm_pt2tab == NULL) {
2240 			/*
2241 			 * QQQ: As struct pmap is allocated from UMA with
2242 			 *      UMA_ZONE_NOFREE flag, it's important to leave
2243 			 *      no allocation in pmap if initialization failed.
2244 			 */
2245 			kmem_free((vm_offset_t)pmap->pm_pt1, NB_IN_PT1);
2246 			pmap->pm_pt1 = NULL;
2247 			return (0);
2248 		}
2249 		/*
2250 		 * QQQ: Each L2 page table page vm_page_t has pindex set to
2251 		 *      pte1 index of virtual address mapped by this page.
2252 		 *      It's not valid for non kernel PT2TABs themselves.
2253 		 *      The pindex of these pages can not be altered because
2254 		 *      of the way how they are allocated now. However, it
2255 		 *      should not be a problem.
2256 		 */
2257 	}
2258 
2259 	mtx_lock_spin(&allpmaps_lock);
2260 	/*
2261 	 * To avoid race with pmap_kenter_pte1() and pmap_kenter_pt2tab(),
2262 	 * kernel_vm_end_new is used here instead of kernel_vm_end.
2263 	 */
2264 	pte1_copy_nosync(kern_pt1, pmap->pm_pt1, KERNBASE,
2265 	    kernel_vm_end_new - 1);
2266 	pte1_copy_nosync(kern_pt1, pmap->pm_pt1, vm_max_kernel_address,
2267 	    0xFFFFFFFF);
2268 	pt2tab_copy_nosync(kern_pt2tab, pmap->pm_pt2tab, KERNBASE,
2269 	    kernel_vm_end_new - 1);
2270 	pt2tab_copy_nosync(kern_pt2tab, pmap->pm_pt2tab, vm_max_kernel_address,
2271 	    0xFFFFFFFF);
2272 	LIST_INSERT_HEAD(&allpmaps, pmap, pm_list);
2273 	mtx_unlock_spin(&allpmaps_lock);
2274 
2275 	/*
2276 	 * Store PT2MAP PT2 pages (a.k.a. PT2TAB) in PT2TAB itself.
2277 	 * I.e. self reference mapping.  The PT2TAB is private, however mapped
2278 	 * into shared PT2MAP space, so the mapping should be not global.
2279 	 */
2280 	pt2tab_pa = vtophys(pmap->pm_pt2tab);
2281 	pte2p = pmap_pt2tab_entry(pmap, (vm_offset_t)PT2MAP);
2282 	for (pa = pt2tab_pa, i = 0; i < NPG_IN_PT2TAB; i++, pa += PTE2_SIZE) {
2283 		pt2tab_store(pte2p++, PTE2_KPT_NG(pa));
2284 	}
2285 
2286 	/* Insert PT2MAP PT2s into pmap PT1. */
2287 	pte1p = pmap_pte1(pmap, (vm_offset_t)PT2MAP);
2288 	for (pa = pt2tab_pa, i = 0; i < NPT2_IN_PT2TAB; i++, pa += NB_IN_PT2) {
2289 		pte1_store(pte1p++, PTE1_LINK(pa));
2290 	}
2291 
2292 	/*
2293 	 * Now synchronize new mapping which was made above.
2294 	 */
2295 	pte1_sync_range(pmap->pm_pt1, NB_IN_PT1);
2296 	pte2_sync_range(pmap->pm_pt2tab, NB_IN_PT2TAB);
2297 
2298 	CPU_ZERO(&pmap->pm_active);
2299 	TAILQ_INIT(&pmap->pm_pvchunk);
2300 	bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
2301 
2302 	return (1);
2303 }
2304 
2305 #ifdef INVARIANTS
2306 static boolean_t
2307 pt2tab_user_is_empty(pt2_entry_t *tab)
2308 {
2309 	u_int i, end;
2310 
2311 	end = pt2tab_index(VM_MAXUSER_ADDRESS);
2312 	for (i = 0; i < end; i++)
2313 		if (tab[i] != 0) return (FALSE);
2314 	return (TRUE);
2315 }
2316 #endif
2317 /*
2318  *  Release any resources held by the given physical map.
2319  *  Called when a pmap initialized by pmap_pinit is being released.
2320  *  Should only be called if the map contains no valid mappings.
2321  */
2322 void
2323 pmap_release(pmap_t pmap)
2324 {
2325 #ifdef INVARIANTS
2326 	vm_offset_t start, end;
2327 #endif
2328 	KASSERT(pmap->pm_stats.resident_count == 0,
2329 	    ("%s: pmap resident count %ld != 0", __func__,
2330 	    pmap->pm_stats.resident_count));
2331 	KASSERT(pt2tab_user_is_empty(pmap->pm_pt2tab),
2332 	    ("%s: has allocated user PT2(s)", __func__));
2333 	KASSERT(CPU_EMPTY(&pmap->pm_active),
2334 	    ("%s: pmap %p is active on some CPU(s)", __func__, pmap));
2335 
2336 	mtx_lock_spin(&allpmaps_lock);
2337 	LIST_REMOVE(pmap, pm_list);
2338 	mtx_unlock_spin(&allpmaps_lock);
2339 
2340 #ifdef INVARIANTS
2341 	start = pte1_index(KERNBASE) * sizeof(pt1_entry_t);
2342 	end = (pte1_index(0xFFFFFFFF) + 1) * sizeof(pt1_entry_t);
2343 	bzero((char *)pmap->pm_pt1 + start, end - start);
2344 
2345 	start = pt2tab_index(KERNBASE) * sizeof(pt2_entry_t);
2346 	end = (pt2tab_index(0xFFFFFFFF) + 1) * sizeof(pt2_entry_t);
2347 	bzero((char *)pmap->pm_pt2tab + start, end - start);
2348 #endif
2349 	/*
2350 	 * We are leaving PT1 and PT2TAB allocated on released pmap,
2351 	 * so hopefully UMA vmspace_zone will always be inited with
2352 	 * UMA_ZONE_NOFREE flag.
2353 	 */
2354 }
2355 
2356 /*********************************************************
2357  *
2358  *  L2 table pages and their pages management routines.
2359  *
2360  *********************************************************/
2361 
2362 /*
2363  *  Virtual interface for L2 page table wire counting.
2364  *
2365  *  Each L2 page table in a page has own counter which counts a number of
2366  *  valid mappings in a table. Global page counter counts mappings in all
2367  *  tables in a page plus a single itself mapping in PT2TAB.
2368  *
2369  *  During a promotion we leave the associated L2 page table counter
2370  *  untouched, so the table (strictly speaking a page which holds it)
2371  *  is never freed if promoted.
2372  *
2373  *  If a page m->wire_count == 1 then no valid mappings exist in any L2 page
2374  *  table in the page and the page itself is only mapped in PT2TAB.
2375  */
2376 
2377 static __inline void
2378 pt2_wirecount_init(vm_page_t m)
2379 {
2380 	u_int i;
2381 
2382 	/*
2383 	 * Note: A page m is allocated with VM_ALLOC_WIRED flag and
2384 	 *       m->wire_count should be already set correctly.
2385 	 *       So, there is no need to set it again herein.
2386 	 */
2387 	for (i = 0; i < NPT2_IN_PG; i++)
2388 		m->md.pt2_wirecount[i] = 0;
2389 }
2390 
2391 static __inline void
2392 pt2_wirecount_inc(vm_page_t m, uint32_t pte1_idx)
2393 {
2394 
2395 	/*
2396 	 * Note: A just modificated pte2 (i.e. already allocated)
2397 	 *       is acquiring one extra reference which must be
2398 	 *       explicitly cleared. It influences the KASSERTs herein.
2399 	 *       All L2 page tables in a page always belong to the same
2400 	 *       pmap, so we allow only one extra reference for the page.
2401 	 */
2402 	KASSERT(m->md.pt2_wirecount[pte1_idx & PT2PG_MASK] < (NPTE2_IN_PT2 + 1),
2403 	    ("%s: PT2 is overflowing ...", __func__));
2404 	KASSERT(m->wire_count <= (NPTE2_IN_PG + 1),
2405 	    ("%s: PT2PG is overflowing ...", __func__));
2406 
2407 	m->wire_count++;
2408 	m->md.pt2_wirecount[pte1_idx & PT2PG_MASK]++;
2409 }
2410 
2411 static __inline void
2412 pt2_wirecount_dec(vm_page_t m, uint32_t pte1_idx)
2413 {
2414 
2415 	KASSERT(m->md.pt2_wirecount[pte1_idx & PT2PG_MASK] != 0,
2416 	    ("%s: PT2 is underflowing ...", __func__));
2417 	KASSERT(m->wire_count > 1,
2418 	    ("%s: PT2PG is underflowing ...", __func__));
2419 
2420 	m->wire_count--;
2421 	m->md.pt2_wirecount[pte1_idx & PT2PG_MASK]--;
2422 }
2423 
2424 static __inline void
2425 pt2_wirecount_set(vm_page_t m, uint32_t pte1_idx, uint16_t count)
2426 {
2427 
2428 	KASSERT(count <= NPTE2_IN_PT2,
2429 	    ("%s: invalid count %u", __func__, count));
2430 	KASSERT(m->wire_count >  m->md.pt2_wirecount[pte1_idx & PT2PG_MASK],
2431 	    ("%s: PT2PG corrupting (%u, %u) ...", __func__, m->wire_count,
2432 	    m->md.pt2_wirecount[pte1_idx & PT2PG_MASK]));
2433 
2434 	m->wire_count -= m->md.pt2_wirecount[pte1_idx & PT2PG_MASK];
2435 	m->wire_count += count;
2436 	m->md.pt2_wirecount[pte1_idx & PT2PG_MASK] = count;
2437 
2438 	KASSERT(m->wire_count <= (NPTE2_IN_PG + 1),
2439 	    ("%s: PT2PG is overflowed (%u) ...", __func__, m->wire_count));
2440 }
2441 
2442 static __inline uint32_t
2443 pt2_wirecount_get(vm_page_t m, uint32_t pte1_idx)
2444 {
2445 
2446 	return (m->md.pt2_wirecount[pte1_idx & PT2PG_MASK]);
2447 }
2448 
2449 static __inline boolean_t
2450 pt2_is_empty(vm_page_t m, vm_offset_t va)
2451 {
2452 
2453 	return (m->md.pt2_wirecount[pte1_index(va) & PT2PG_MASK] == 0);
2454 }
2455 
2456 static __inline boolean_t
2457 pt2_is_full(vm_page_t m, vm_offset_t va)
2458 {
2459 
2460 	return (m->md.pt2_wirecount[pte1_index(va) & PT2PG_MASK] ==
2461 	    NPTE2_IN_PT2);
2462 }
2463 
2464 static __inline boolean_t
2465 pt2pg_is_empty(vm_page_t m)
2466 {
2467 
2468 	return (m->wire_count == 1);
2469 }
2470 
2471 /*
2472  *  This routine is called if the L2 page table
2473  *  is not mapped correctly.
2474  */
2475 static vm_page_t
2476 _pmap_allocpte2(pmap_t pmap, vm_offset_t va, u_int flags)
2477 {
2478 	uint32_t pte1_idx;
2479 	pt1_entry_t *pte1p;
2480 	pt2_entry_t pte2;
2481 	vm_page_t  m;
2482 	vm_paddr_t pt2pg_pa, pt2_pa;
2483 
2484 	pte1_idx = pte1_index(va);
2485 	pte1p = pmap->pm_pt1 + pte1_idx;
2486 
2487 	KASSERT(pte1_load(pte1p) == 0,
2488 	    ("%s: pm_pt1[%#x] is not zero: %#x", __func__, pte1_idx,
2489 	    pte1_load(pte1p)));
2490 
2491 	pte2 = pt2tab_load(pmap_pt2tab_entry(pmap, va));
2492 	if (!pte2_is_valid(pte2)) {
2493 		/*
2494 		 * Install new PT2s page into pmap PT2TAB.
2495 		 */
2496 		m = vm_page_alloc(NULL, pte1_idx & ~PT2PG_MASK,
2497 		    VM_ALLOC_NOOBJ | VM_ALLOC_WIRED | VM_ALLOC_ZERO);
2498 		if (m == NULL) {
2499 			if ((flags & PMAP_ENTER_NOSLEEP) == 0) {
2500 				PMAP_UNLOCK(pmap);
2501 				rw_wunlock(&pvh_global_lock);
2502 				vm_wait(NULL);
2503 				rw_wlock(&pvh_global_lock);
2504 				PMAP_LOCK(pmap);
2505 			}
2506 
2507 			/*
2508 			 * Indicate the need to retry.  While waiting,
2509 			 * the L2 page table page may have been allocated.
2510 			 */
2511 			return (NULL);
2512 		}
2513 		pmap->pm_stats.resident_count++;
2514 		pt2pg_pa = pmap_pt2pg_init(pmap, va, m);
2515 	} else {
2516 		pt2pg_pa = pte2_pa(pte2);
2517 		m = PHYS_TO_VM_PAGE(pt2pg_pa);
2518 	}
2519 
2520 	pt2_wirecount_inc(m, pte1_idx);
2521 	pt2_pa = page_pt2pa(pt2pg_pa, pte1_idx);
2522 	pte1_store(pte1p, PTE1_LINK(pt2_pa));
2523 
2524 	return (m);
2525 }
2526 
2527 static vm_page_t
2528 pmap_allocpte2(pmap_t pmap, vm_offset_t va, u_int flags)
2529 {
2530 	u_int pte1_idx;
2531 	pt1_entry_t *pte1p, pte1;
2532 	vm_page_t m;
2533 
2534 	pte1_idx = pte1_index(va);
2535 retry:
2536 	pte1p = pmap->pm_pt1 + pte1_idx;
2537 	pte1 = pte1_load(pte1p);
2538 
2539 	/*
2540 	 * This supports switching from a 1MB page to a
2541 	 * normal 4K page.
2542 	 */
2543 	if (pte1_is_section(pte1)) {
2544 		(void)pmap_demote_pte1(pmap, pte1p, va);
2545 		/*
2546 		 * Reload pte1 after demotion.
2547 		 *
2548 		 * Note: Demotion can even fail as either PT2 is not find for
2549 		 *       the virtual address or PT2PG can not be allocated.
2550 		 */
2551 		pte1 = pte1_load(pte1p);
2552 	}
2553 
2554 	/*
2555 	 * If the L2 page table page is mapped, we just increment the
2556 	 * hold count, and activate it.
2557 	 */
2558 	if (pte1_is_link(pte1)) {
2559 		m = PHYS_TO_VM_PAGE(pte1_link_pa(pte1));
2560 		pt2_wirecount_inc(m, pte1_idx);
2561 	} else  {
2562 		/*
2563 		 * Here if the PT2 isn't mapped, or if it has
2564 		 * been deallocated.
2565 		 */
2566 		m = _pmap_allocpte2(pmap, va, flags);
2567 		if (m == NULL && (flags & PMAP_ENTER_NOSLEEP) == 0)
2568 			goto retry;
2569 	}
2570 
2571 	return (m);
2572 }
2573 
2574 /*
2575  *  Schedule the specified unused L2 page table page to be freed. Specifically,
2576  *  add the page to the specified list of pages that will be released to the
2577  *  physical memory manager after the TLB has been updated.
2578  */
2579 static __inline void
2580 pmap_add_delayed_free_list(vm_page_t m, struct spglist *free)
2581 {
2582 
2583 	/*
2584 	 * Put page on a list so that it is released after
2585 	 * *ALL* TLB shootdown is done
2586 	 */
2587 #ifdef PMAP_DEBUG
2588 	pmap_zero_page_check(m);
2589 #endif
2590 	m->flags |= PG_ZERO;
2591 	SLIST_INSERT_HEAD(free, m, plinks.s.ss);
2592 }
2593 
2594 /*
2595  *  Unwire L2 page tables page.
2596  */
2597 static void
2598 pmap_unwire_pt2pg(pmap_t pmap, vm_offset_t va, vm_page_t m)
2599 {
2600 	pt1_entry_t *pte1p, opte1 __unused;
2601 	pt2_entry_t *pte2p;
2602 	uint32_t i;
2603 
2604 	KASSERT(pt2pg_is_empty(m),
2605 	    ("%s: pmap %p PT2PG %p wired", __func__, pmap, m));
2606 
2607 	/*
2608 	 * Unmap all L2 page tables in the page from L1 page table.
2609 	 *
2610 	 * QQQ: Individual L2 page tables (except the last one) can be unmapped
2611 	 * earlier. However, we are doing that this way.
2612 	 */
2613 	KASSERT(m->pindex == (pte1_index(va) & ~PT2PG_MASK),
2614 	    ("%s: pmap %p va %#x PT2PG %p bad index", __func__, pmap, va, m));
2615 	pte1p = pmap->pm_pt1 + m->pindex;
2616 	for (i = 0; i < NPT2_IN_PG; i++, pte1p++) {
2617 		KASSERT(m->md.pt2_wirecount[i] == 0,
2618 		    ("%s: pmap %p PT2 %u (PG %p) wired", __func__, pmap, i, m));
2619 		opte1 = pte1_load(pte1p);
2620 		if (pte1_is_link(opte1)) {
2621 			pte1_clear(pte1p);
2622 			/*
2623 			 * Flush intermediate TLB cache.
2624 			 */
2625 			pmap_tlb_flush(pmap, (m->pindex + i) << PTE1_SHIFT);
2626 		}
2627 #ifdef INVARIANTS
2628 		else
2629 			KASSERT((opte1 == 0) || pte1_is_section(opte1),
2630 			    ("%s: pmap %p va %#x bad pte1 %x at %u", __func__,
2631 			    pmap, va, opte1, i));
2632 #endif
2633 	}
2634 
2635 	/*
2636 	 * Unmap the page from PT2TAB.
2637 	 */
2638 	pte2p = pmap_pt2tab_entry(pmap, va);
2639 	(void)pt2tab_load_clear(pte2p);
2640 	pmap_tlb_flush(pmap, pt2map_pt2pg(va));
2641 
2642 	m->wire_count = 0;
2643 	pmap->pm_stats.resident_count--;
2644 
2645 	/*
2646 	 * This barrier is so that the ordinary store unmapping
2647 	 * the L2 page table page is globally performed before TLB shoot-
2648 	 * down is begun.
2649 	 */
2650 	wmb();
2651 	vm_wire_sub(1);
2652 }
2653 
2654 /*
2655  *  Decrements a L2 page table page's wire count, which is used to record the
2656  *  number of valid page table entries within the page.  If the wire count
2657  *  drops to zero, then the page table page is unmapped.  Returns TRUE if the
2658  *  page table page was unmapped and FALSE otherwise.
2659  */
2660 static __inline boolean_t
2661 pmap_unwire_pt2(pmap_t pmap, vm_offset_t va, vm_page_t m, struct spglist *free)
2662 {
2663 	pt2_wirecount_dec(m, pte1_index(va));
2664 	if (pt2pg_is_empty(m)) {
2665 		/*
2666 		 * QQQ: Wire count is zero, so whole page should be zero and
2667 		 *      we can set PG_ZERO flag to it.
2668 		 *      Note that when promotion is enabled, it takes some
2669 		 *      more efforts. See pmap_unwire_pt2_all() below.
2670 		 */
2671 		pmap_unwire_pt2pg(pmap, va, m);
2672 		pmap_add_delayed_free_list(m, free);
2673 		return (TRUE);
2674 	} else
2675 		return (FALSE);
2676 }
2677 
2678 /*
2679  *  Drop a L2 page table page's wire count at once, which is used to record
2680  *  the number of valid L2 page table entries within the page. If the wire
2681  *  count drops to zero, then the L2 page table page is unmapped.
2682  */
2683 static __inline void
2684 pmap_unwire_pt2_all(pmap_t pmap, vm_offset_t va, vm_page_t m,
2685     struct spglist *free)
2686 {
2687 	u_int pte1_idx = pte1_index(va);
2688 
2689 	KASSERT(m->pindex == (pte1_idx & ~PT2PG_MASK),
2690 		("%s: PT2 page's pindex is wrong", __func__));
2691 	KASSERT(m->wire_count > pt2_wirecount_get(m, pte1_idx),
2692 	    ("%s: bad pt2 wire count %u > %u", __func__, m->wire_count,
2693 	    pt2_wirecount_get(m, pte1_idx)));
2694 
2695 	/*
2696 	 * It's possible that the L2 page table was never used.
2697 	 * It happened in case that a section was created without promotion.
2698 	 */
2699 	if (pt2_is_full(m, va)) {
2700 		pt2_wirecount_set(m, pte1_idx, 0);
2701 
2702 		/*
2703 		 * QQQ: We clear L2 page table now, so when L2 page table page
2704 		 *      is going to be freed, we can set it PG_ZERO flag ...
2705 		 *      This function is called only on section mappings, so
2706 		 *      hopefully it's not to big overload.
2707 		 *
2708 		 * XXX: If pmap is current, existing PT2MAP mapping could be
2709 		 *      used for zeroing.
2710 		 */
2711 		pmap_zero_page_area(m, page_pt2off(pte1_idx), NB_IN_PT2);
2712 	}
2713 #ifdef INVARIANTS
2714 	else
2715 		KASSERT(pt2_is_empty(m, va), ("%s: PT2 is not empty (%u)",
2716 		    __func__, pt2_wirecount_get(m, pte1_idx)));
2717 #endif
2718 	if (pt2pg_is_empty(m)) {
2719 		pmap_unwire_pt2pg(pmap, va, m);
2720 		pmap_add_delayed_free_list(m, free);
2721 	}
2722 }
2723 
2724 /*
2725  *  After removing a L2 page table entry, this routine is used to
2726  *  conditionally free the page, and manage the hold/wire counts.
2727  */
2728 static boolean_t
2729 pmap_unuse_pt2(pmap_t pmap, vm_offset_t va, struct spglist *free)
2730 {
2731 	pt1_entry_t pte1;
2732 	vm_page_t mpte;
2733 
2734 	if (va >= VM_MAXUSER_ADDRESS)
2735 		return (FALSE);
2736 	pte1 = pte1_load(pmap_pte1(pmap, va));
2737 	mpte = PHYS_TO_VM_PAGE(pte1_link_pa(pte1));
2738 	return (pmap_unwire_pt2(pmap, va, mpte, free));
2739 }
2740 
2741 /*************************************
2742  *
2743  *  Page management routines.
2744  *
2745  *************************************/
2746 
2747 CTASSERT(sizeof(struct pv_chunk) == PAGE_SIZE);
2748 CTASSERT(_NPCM == 11);
2749 CTASSERT(_NPCPV == 336);
2750 
2751 static __inline struct pv_chunk *
2752 pv_to_chunk(pv_entry_t pv)
2753 {
2754 
2755 	return ((struct pv_chunk *)((uintptr_t)pv & ~(uintptr_t)PAGE_MASK));
2756 }
2757 
2758 #define PV_PMAP(pv) (pv_to_chunk(pv)->pc_pmap)
2759 
2760 #define	PC_FREE0_9	0xfffffffful	/* Free values for index 0 through 9 */
2761 #define	PC_FREE10	0x0000fffful	/* Free values for index 10 */
2762 
2763 static const uint32_t pc_freemask[_NPCM] = {
2764 	PC_FREE0_9, PC_FREE0_9, PC_FREE0_9,
2765 	PC_FREE0_9, PC_FREE0_9, PC_FREE0_9,
2766 	PC_FREE0_9, PC_FREE0_9, PC_FREE0_9,
2767 	PC_FREE0_9, PC_FREE10
2768 };
2769 
2770 SYSCTL_INT(_vm_pmap, OID_AUTO, pv_entry_count, CTLFLAG_RD, &pv_entry_count, 0,
2771 	"Current number of pv entries");
2772 
2773 #ifdef PV_STATS
2774 static int pc_chunk_count, pc_chunk_allocs, pc_chunk_frees, pc_chunk_tryfail;
2775 
2776 SYSCTL_INT(_vm_pmap, OID_AUTO, pc_chunk_count, CTLFLAG_RD, &pc_chunk_count, 0,
2777     "Current number of pv entry chunks");
2778 SYSCTL_INT(_vm_pmap, OID_AUTO, pc_chunk_allocs, CTLFLAG_RD, &pc_chunk_allocs, 0,
2779     "Current number of pv entry chunks allocated");
2780 SYSCTL_INT(_vm_pmap, OID_AUTO, pc_chunk_frees, CTLFLAG_RD, &pc_chunk_frees, 0,
2781     "Current number of pv entry chunks frees");
2782 SYSCTL_INT(_vm_pmap, OID_AUTO, pc_chunk_tryfail, CTLFLAG_RD, &pc_chunk_tryfail,
2783     0, "Number of times tried to get a chunk page but failed.");
2784 
2785 static long pv_entry_frees, pv_entry_allocs;
2786 static int pv_entry_spare;
2787 
2788 SYSCTL_LONG(_vm_pmap, OID_AUTO, pv_entry_frees, CTLFLAG_RD, &pv_entry_frees, 0,
2789     "Current number of pv entry frees");
2790 SYSCTL_LONG(_vm_pmap, OID_AUTO, pv_entry_allocs, CTLFLAG_RD, &pv_entry_allocs,
2791     0, "Current number of pv entry allocs");
2792 SYSCTL_INT(_vm_pmap, OID_AUTO, pv_entry_spare, CTLFLAG_RD, &pv_entry_spare, 0,
2793     "Current number of spare pv entries");
2794 #endif
2795 
2796 /*
2797  *  Is given page managed?
2798  */
2799 static __inline bool
2800 is_managed(vm_paddr_t pa)
2801 {
2802 	vm_page_t m;
2803 
2804 	m = PHYS_TO_VM_PAGE(pa);
2805 	if (m == NULL)
2806 		return (false);
2807 	return ((m->oflags & VPO_UNMANAGED) == 0);
2808 }
2809 
2810 static __inline bool
2811 pte1_is_managed(pt1_entry_t pte1)
2812 {
2813 
2814 	return (is_managed(pte1_pa(pte1)));
2815 }
2816 
2817 static __inline bool
2818 pte2_is_managed(pt2_entry_t pte2)
2819 {
2820 
2821 	return (is_managed(pte2_pa(pte2)));
2822 }
2823 
2824 /*
2825  *  We are in a serious low memory condition.  Resort to
2826  *  drastic measures to free some pages so we can allocate
2827  *  another pv entry chunk.
2828  */
2829 static vm_page_t
2830 pmap_pv_reclaim(pmap_t locked_pmap)
2831 {
2832 	struct pch newtail;
2833 	struct pv_chunk *pc;
2834 	struct md_page *pvh;
2835 	pt1_entry_t *pte1p;
2836 	pmap_t pmap;
2837 	pt2_entry_t *pte2p, tpte2;
2838 	pv_entry_t pv;
2839 	vm_offset_t va;
2840 	vm_page_t m, m_pc;
2841 	struct spglist free;
2842 	uint32_t inuse;
2843 	int bit, field, freed;
2844 
2845 	PMAP_LOCK_ASSERT(locked_pmap, MA_OWNED);
2846 	pmap = NULL;
2847 	m_pc = NULL;
2848 	SLIST_INIT(&free);
2849 	TAILQ_INIT(&newtail);
2850 	while ((pc = TAILQ_FIRST(&pv_chunks)) != NULL && (pv_vafree == 0 ||
2851 	    SLIST_EMPTY(&free))) {
2852 		TAILQ_REMOVE(&pv_chunks, pc, pc_lru);
2853 		if (pmap != pc->pc_pmap) {
2854 			if (pmap != NULL) {
2855 				if (pmap != locked_pmap)
2856 					PMAP_UNLOCK(pmap);
2857 			}
2858 			pmap = pc->pc_pmap;
2859 			/* Avoid deadlock and lock recursion. */
2860 			if (pmap > locked_pmap)
2861 				PMAP_LOCK(pmap);
2862 			else if (pmap != locked_pmap && !PMAP_TRYLOCK(pmap)) {
2863 				pmap = NULL;
2864 				TAILQ_INSERT_TAIL(&newtail, pc, pc_lru);
2865 				continue;
2866 			}
2867 		}
2868 
2869 		/*
2870 		 * Destroy every non-wired, 4 KB page mapping in the chunk.
2871 		 */
2872 		freed = 0;
2873 		for (field = 0; field < _NPCM; field++) {
2874 			for (inuse = ~pc->pc_map[field] & pc_freemask[field];
2875 			    inuse != 0; inuse &= ~(1UL << bit)) {
2876 				bit = ffs(inuse) - 1;
2877 				pv = &pc->pc_pventry[field * 32 + bit];
2878 				va = pv->pv_va;
2879 				pte1p = pmap_pte1(pmap, va);
2880 				if (pte1_is_section(pte1_load(pte1p)))
2881 					continue;
2882 				pte2p = pmap_pte2(pmap, va);
2883 				tpte2 = pte2_load(pte2p);
2884 				if ((tpte2 & PTE2_W) == 0)
2885 					tpte2 = pte2_load_clear(pte2p);
2886 				pmap_pte2_release(pte2p);
2887 				if ((tpte2 & PTE2_W) != 0)
2888 					continue;
2889 				KASSERT(tpte2 != 0,
2890 				    ("pmap_pv_reclaim: pmap %p va %#x zero pte",
2891 				    pmap, va));
2892 				pmap_tlb_flush(pmap, va);
2893 				m = PHYS_TO_VM_PAGE(pte2_pa(tpte2));
2894 				if (pte2_is_dirty(tpte2))
2895 					vm_page_dirty(m);
2896 				if ((tpte2 & PTE2_A) != 0)
2897 					vm_page_aflag_set(m, PGA_REFERENCED);
2898 				TAILQ_REMOVE(&m->md.pv_list, pv, pv_next);
2899 				if (TAILQ_EMPTY(&m->md.pv_list) &&
2900 				    (m->flags & PG_FICTITIOUS) == 0) {
2901 					pvh = pa_to_pvh(VM_PAGE_TO_PHYS(m));
2902 					if (TAILQ_EMPTY(&pvh->pv_list)) {
2903 						vm_page_aflag_clear(m,
2904 						    PGA_WRITEABLE);
2905 					}
2906 				}
2907 				pc->pc_map[field] |= 1UL << bit;
2908 				pmap_unuse_pt2(pmap, va, &free);
2909 				freed++;
2910 			}
2911 		}
2912 		if (freed == 0) {
2913 			TAILQ_INSERT_TAIL(&newtail, pc, pc_lru);
2914 			continue;
2915 		}
2916 		/* Every freed mapping is for a 4 KB page. */
2917 		pmap->pm_stats.resident_count -= freed;
2918 		PV_STAT(pv_entry_frees += freed);
2919 		PV_STAT(pv_entry_spare += freed);
2920 		pv_entry_count -= freed;
2921 		TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
2922 		for (field = 0; field < _NPCM; field++)
2923 			if (pc->pc_map[field] != pc_freemask[field]) {
2924 				TAILQ_INSERT_HEAD(&pmap->pm_pvchunk, pc,
2925 				    pc_list);
2926 				TAILQ_INSERT_TAIL(&newtail, pc, pc_lru);
2927 
2928 				/*
2929 				 * One freed pv entry in locked_pmap is
2930 				 * sufficient.
2931 				 */
2932 				if (pmap == locked_pmap)
2933 					goto out;
2934 				break;
2935 			}
2936 		if (field == _NPCM) {
2937 			PV_STAT(pv_entry_spare -= _NPCPV);
2938 			PV_STAT(pc_chunk_count--);
2939 			PV_STAT(pc_chunk_frees++);
2940 			/* Entire chunk is free; return it. */
2941 			m_pc = PHYS_TO_VM_PAGE(pmap_kextract((vm_offset_t)pc));
2942 			pmap_qremove((vm_offset_t)pc, 1);
2943 			pmap_pte2list_free(&pv_vafree, (vm_offset_t)pc);
2944 			break;
2945 		}
2946 	}
2947 out:
2948 	TAILQ_CONCAT(&pv_chunks, &newtail, pc_lru);
2949 	if (pmap != NULL) {
2950 		if (pmap != locked_pmap)
2951 			PMAP_UNLOCK(pmap);
2952 	}
2953 	if (m_pc == NULL && pv_vafree != 0 && SLIST_EMPTY(&free)) {
2954 		m_pc = SLIST_FIRST(&free);
2955 		SLIST_REMOVE_HEAD(&free, plinks.s.ss);
2956 		/* Recycle a freed page table page. */
2957 		m_pc->wire_count = 1;
2958 		vm_wire_add(1);
2959 	}
2960 	vm_page_free_pages_toq(&free, false);
2961 	return (m_pc);
2962 }
2963 
2964 static void
2965 free_pv_chunk(struct pv_chunk *pc)
2966 {
2967 	vm_page_t m;
2968 
2969 	TAILQ_REMOVE(&pv_chunks, pc, pc_lru);
2970 	PV_STAT(pv_entry_spare -= _NPCPV);
2971 	PV_STAT(pc_chunk_count--);
2972 	PV_STAT(pc_chunk_frees++);
2973 	/* entire chunk is free, return it */
2974 	m = PHYS_TO_VM_PAGE(pmap_kextract((vm_offset_t)pc));
2975 	pmap_qremove((vm_offset_t)pc, 1);
2976 	vm_page_unwire(m, PQ_NONE);
2977 	vm_page_free(m);
2978 	pmap_pte2list_free(&pv_vafree, (vm_offset_t)pc);
2979 }
2980 
2981 /*
2982  *  Free the pv_entry back to the free list.
2983  */
2984 static void
2985 free_pv_entry(pmap_t pmap, pv_entry_t pv)
2986 {
2987 	struct pv_chunk *pc;
2988 	int idx, field, bit;
2989 
2990 	rw_assert(&pvh_global_lock, RA_WLOCKED);
2991 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
2992 	PV_STAT(pv_entry_frees++);
2993 	PV_STAT(pv_entry_spare++);
2994 	pv_entry_count--;
2995 	pc = pv_to_chunk(pv);
2996 	idx = pv - &pc->pc_pventry[0];
2997 	field = idx / 32;
2998 	bit = idx % 32;
2999 	pc->pc_map[field] |= 1ul << bit;
3000 	for (idx = 0; idx < _NPCM; idx++)
3001 		if (pc->pc_map[idx] != pc_freemask[idx]) {
3002 			/*
3003 			 * 98% of the time, pc is already at the head of the
3004 			 * list.  If it isn't already, move it to the head.
3005 			 */
3006 			if (__predict_false(TAILQ_FIRST(&pmap->pm_pvchunk) !=
3007 			    pc)) {
3008 				TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
3009 				TAILQ_INSERT_HEAD(&pmap->pm_pvchunk, pc,
3010 				    pc_list);
3011 			}
3012 			return;
3013 		}
3014 	TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
3015 	free_pv_chunk(pc);
3016 }
3017 
3018 /*
3019  *  Get a new pv_entry, allocating a block from the system
3020  *  when needed.
3021  */
3022 static pv_entry_t
3023 get_pv_entry(pmap_t pmap, boolean_t try)
3024 {
3025 	static const struct timeval printinterval = { 60, 0 };
3026 	static struct timeval lastprint;
3027 	int bit, field;
3028 	pv_entry_t pv;
3029 	struct pv_chunk *pc;
3030 	vm_page_t m;
3031 
3032 	rw_assert(&pvh_global_lock, RA_WLOCKED);
3033 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
3034 	PV_STAT(pv_entry_allocs++);
3035 	pv_entry_count++;
3036 	if (pv_entry_count > pv_entry_high_water)
3037 		if (ratecheck(&lastprint, &printinterval))
3038 			printf("Approaching the limit on PV entries, consider "
3039 			    "increasing either the vm.pmap.shpgperproc or the "
3040 			    "vm.pmap.pv_entries tunable.\n");
3041 retry:
3042 	pc = TAILQ_FIRST(&pmap->pm_pvchunk);
3043 	if (pc != NULL) {
3044 		for (field = 0; field < _NPCM; field++) {
3045 			if (pc->pc_map[field]) {
3046 				bit = ffs(pc->pc_map[field]) - 1;
3047 				break;
3048 			}
3049 		}
3050 		if (field < _NPCM) {
3051 			pv = &pc->pc_pventry[field * 32 + bit];
3052 			pc->pc_map[field] &= ~(1ul << bit);
3053 			/* If this was the last item, move it to tail */
3054 			for (field = 0; field < _NPCM; field++)
3055 				if (pc->pc_map[field] != 0) {
3056 					PV_STAT(pv_entry_spare--);
3057 					return (pv);	/* not full, return */
3058 				}
3059 			TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
3060 			TAILQ_INSERT_TAIL(&pmap->pm_pvchunk, pc, pc_list);
3061 			PV_STAT(pv_entry_spare--);
3062 			return (pv);
3063 		}
3064 	}
3065 	/*
3066 	 * Access to the pte2list "pv_vafree" is synchronized by the pvh
3067 	 * global lock.  If "pv_vafree" is currently non-empty, it will
3068 	 * remain non-empty until pmap_pte2list_alloc() completes.
3069 	 */
3070 	if (pv_vafree == 0 || (m = vm_page_alloc(NULL, 0, VM_ALLOC_NORMAL |
3071 	    VM_ALLOC_NOOBJ | VM_ALLOC_WIRED)) == NULL) {
3072 		if (try) {
3073 			pv_entry_count--;
3074 			PV_STAT(pc_chunk_tryfail++);
3075 			return (NULL);
3076 		}
3077 		m = pmap_pv_reclaim(pmap);
3078 		if (m == NULL)
3079 			goto retry;
3080 	}
3081 	PV_STAT(pc_chunk_count++);
3082 	PV_STAT(pc_chunk_allocs++);
3083 	pc = (struct pv_chunk *)pmap_pte2list_alloc(&pv_vafree);
3084 	pmap_qenter((vm_offset_t)pc, &m, 1);
3085 	pc->pc_pmap = pmap;
3086 	pc->pc_map[0] = pc_freemask[0] & ~1ul;	/* preallocated bit 0 */
3087 	for (field = 1; field < _NPCM; field++)
3088 		pc->pc_map[field] = pc_freemask[field];
3089 	TAILQ_INSERT_TAIL(&pv_chunks, pc, pc_lru);
3090 	pv = &pc->pc_pventry[0];
3091 	TAILQ_INSERT_HEAD(&pmap->pm_pvchunk, pc, pc_list);
3092 	PV_STAT(pv_entry_spare += _NPCPV - 1);
3093 	return (pv);
3094 }
3095 
3096 /*
3097  *  Create a pv entry for page at pa for
3098  *  (pmap, va).
3099  */
3100 static void
3101 pmap_insert_entry(pmap_t pmap, vm_offset_t va, vm_page_t m)
3102 {
3103 	pv_entry_t pv;
3104 
3105 	rw_assert(&pvh_global_lock, RA_WLOCKED);
3106 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
3107 	pv = get_pv_entry(pmap, FALSE);
3108 	pv->pv_va = va;
3109 	TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_next);
3110 }
3111 
3112 static __inline pv_entry_t
3113 pmap_pvh_remove(struct md_page *pvh, pmap_t pmap, vm_offset_t va)
3114 {
3115 	pv_entry_t pv;
3116 
3117 	rw_assert(&pvh_global_lock, RA_WLOCKED);
3118 	TAILQ_FOREACH(pv, &pvh->pv_list, pv_next) {
3119 		if (pmap == PV_PMAP(pv) && va == pv->pv_va) {
3120 			TAILQ_REMOVE(&pvh->pv_list, pv, pv_next);
3121 			break;
3122 		}
3123 	}
3124 	return (pv);
3125 }
3126 
3127 static void
3128 pmap_pvh_free(struct md_page *pvh, pmap_t pmap, vm_offset_t va)
3129 {
3130 	pv_entry_t pv;
3131 
3132 	pv = pmap_pvh_remove(pvh, pmap, va);
3133 	KASSERT(pv != NULL, ("pmap_pvh_free: pv not found"));
3134 	free_pv_entry(pmap, pv);
3135 }
3136 
3137 static void
3138 pmap_remove_entry(pmap_t pmap, vm_page_t m, vm_offset_t va)
3139 {
3140 	struct md_page *pvh;
3141 
3142 	rw_assert(&pvh_global_lock, RA_WLOCKED);
3143 	pmap_pvh_free(&m->md, pmap, va);
3144 	if (TAILQ_EMPTY(&m->md.pv_list) && (m->flags & PG_FICTITIOUS) == 0) {
3145 		pvh = pa_to_pvh(VM_PAGE_TO_PHYS(m));
3146 		if (TAILQ_EMPTY(&pvh->pv_list))
3147 			vm_page_aflag_clear(m, PGA_WRITEABLE);
3148 	}
3149 }
3150 
3151 static void
3152 pmap_pv_demote_pte1(pmap_t pmap, vm_offset_t va, vm_paddr_t pa)
3153 {
3154 	struct md_page *pvh;
3155 	pv_entry_t pv;
3156 	vm_offset_t va_last;
3157 	vm_page_t m;
3158 
3159 	rw_assert(&pvh_global_lock, RA_WLOCKED);
3160 	KASSERT((pa & PTE1_OFFSET) == 0,
3161 	    ("pmap_pv_demote_pte1: pa is not 1mpage aligned"));
3162 
3163 	/*
3164 	 * Transfer the 1mpage's pv entry for this mapping to the first
3165 	 * page's pv list.
3166 	 */
3167 	pvh = pa_to_pvh(pa);
3168 	va = pte1_trunc(va);
3169 	pv = pmap_pvh_remove(pvh, pmap, va);
3170 	KASSERT(pv != NULL, ("pmap_pv_demote_pte1: pv not found"));
3171 	m = PHYS_TO_VM_PAGE(pa);
3172 	TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_next);
3173 	/* Instantiate the remaining NPTE2_IN_PT2 - 1 pv entries. */
3174 	va_last = va + PTE1_SIZE - PAGE_SIZE;
3175 	do {
3176 		m++;
3177 		KASSERT((m->oflags & VPO_UNMANAGED) == 0,
3178 		    ("pmap_pv_demote_pte1: page %p is not managed", m));
3179 		va += PAGE_SIZE;
3180 		pmap_insert_entry(pmap, va, m);
3181 	} while (va < va_last);
3182 }
3183 
3184 #if VM_NRESERVLEVEL > 0
3185 static void
3186 pmap_pv_promote_pte1(pmap_t pmap, vm_offset_t va, vm_paddr_t pa)
3187 {
3188 	struct md_page *pvh;
3189 	pv_entry_t pv;
3190 	vm_offset_t va_last;
3191 	vm_page_t m;
3192 
3193 	rw_assert(&pvh_global_lock, RA_WLOCKED);
3194 	KASSERT((pa & PTE1_OFFSET) == 0,
3195 	    ("pmap_pv_promote_pte1: pa is not 1mpage aligned"));
3196 
3197 	/*
3198 	 * Transfer the first page's pv entry for this mapping to the
3199 	 * 1mpage's pv list.  Aside from avoiding the cost of a call
3200 	 * to get_pv_entry(), a transfer avoids the possibility that
3201 	 * get_pv_entry() calls pmap_pv_reclaim() and that pmap_pv_reclaim()
3202 	 * removes one of the mappings that is being promoted.
3203 	 */
3204 	m = PHYS_TO_VM_PAGE(pa);
3205 	va = pte1_trunc(va);
3206 	pv = pmap_pvh_remove(&m->md, pmap, va);
3207 	KASSERT(pv != NULL, ("pmap_pv_promote_pte1: pv not found"));
3208 	pvh = pa_to_pvh(pa);
3209 	TAILQ_INSERT_TAIL(&pvh->pv_list, pv, pv_next);
3210 	/* Free the remaining NPTE2_IN_PT2 - 1 pv entries. */
3211 	va_last = va + PTE1_SIZE - PAGE_SIZE;
3212 	do {
3213 		m++;
3214 		va += PAGE_SIZE;
3215 		pmap_pvh_free(&m->md, pmap, va);
3216 	} while (va < va_last);
3217 }
3218 #endif
3219 
3220 /*
3221  *  Conditionally create a pv entry.
3222  */
3223 static boolean_t
3224 pmap_try_insert_pv_entry(pmap_t pmap, vm_offset_t va, vm_page_t m)
3225 {
3226 	pv_entry_t pv;
3227 
3228 	rw_assert(&pvh_global_lock, RA_WLOCKED);
3229 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
3230 	if (pv_entry_count < pv_entry_high_water &&
3231 	    (pv = get_pv_entry(pmap, TRUE)) != NULL) {
3232 		pv->pv_va = va;
3233 		TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_next);
3234 		return (TRUE);
3235 	} else
3236 		return (FALSE);
3237 }
3238 
3239 /*
3240  *  Create the pv entries for each of the pages within a section.
3241  */
3242 static bool
3243 pmap_pv_insert_pte1(pmap_t pmap, vm_offset_t va, pt1_entry_t pte1, u_int flags)
3244 {
3245 	struct md_page *pvh;
3246 	pv_entry_t pv;
3247 	bool noreclaim;
3248 
3249 	rw_assert(&pvh_global_lock, RA_WLOCKED);
3250 	noreclaim = (flags & PMAP_ENTER_NORECLAIM) != 0;
3251 	if ((noreclaim && pv_entry_count >= pv_entry_high_water) ||
3252 	    (pv = get_pv_entry(pmap, noreclaim)) == NULL)
3253 		return (false);
3254 	pv->pv_va = va;
3255 	pvh = pa_to_pvh(pte1_pa(pte1));
3256 	TAILQ_INSERT_TAIL(&pvh->pv_list, pv, pv_next);
3257 	return (true);
3258 }
3259 
3260 static inline void
3261 pmap_tlb_flush_pte1(pmap_t pmap, vm_offset_t va, pt1_entry_t npte1)
3262 {
3263 
3264 	/* Kill all the small mappings or the big one only. */
3265 	if (pte1_is_section(npte1))
3266 		pmap_tlb_flush_range(pmap, pte1_trunc(va), PTE1_SIZE);
3267 	else
3268 		pmap_tlb_flush(pmap, pte1_trunc(va));
3269 }
3270 
3271 /*
3272  *  Update kernel pte1 on all pmaps.
3273  *
3274  *  The following function is called only on one cpu with disabled interrupts.
3275  *  In SMP case, smp_rendezvous_cpus() is used to stop other cpus. This way
3276  *  nobody can invoke explicit hardware table walk during the update of pte1.
3277  *  Unsolicited hardware table walk can still happen, invoked by speculative
3278  *  data or instruction prefetch or even by speculative hardware table walk.
3279  *
3280  *  The break-before-make approach should be implemented here. However, it's
3281  *  not so easy to do that for kernel mappings as it would be unhappy to unmap
3282  *  itself unexpectedly but voluntarily.
3283  */
3284 static void
3285 pmap_update_pte1_kernel(vm_offset_t va, pt1_entry_t npte1)
3286 {
3287 	pmap_t pmap;
3288 	pt1_entry_t *pte1p;
3289 
3290 	/*
3291 	 * Get current pmap. Interrupts should be disabled here
3292 	 * so PCPU_GET() is done atomically.
3293 	 */
3294 	pmap = PCPU_GET(curpmap);
3295 	if (pmap == NULL)
3296 		pmap = kernel_pmap;
3297 
3298 	/*
3299 	 * (1) Change pte1 on current pmap.
3300 	 * (2) Flush all obsolete TLB entries on current CPU.
3301 	 * (3) Change pte1 on all pmaps.
3302 	 * (4) Flush all obsolete TLB entries on all CPUs in SMP case.
3303 	 */
3304 
3305 	pte1p = pmap_pte1(pmap, va);
3306 	pte1_store(pte1p, npte1);
3307 
3308 	/* Kill all the small mappings or the big one only. */
3309 	if (pte1_is_section(npte1)) {
3310 		pmap_pte1_kern_promotions++;
3311 		tlb_flush_range_local(pte1_trunc(va), PTE1_SIZE);
3312 	} else {
3313 		pmap_pte1_kern_demotions++;
3314 		tlb_flush_local(pte1_trunc(va));
3315 	}
3316 
3317 	/*
3318 	 * In SMP case, this function is called when all cpus are at smp
3319 	 * rendezvous, so there is no need to use 'allpmaps_lock' lock here.
3320 	 * In UP case, the function is called with this lock locked.
3321 	 */
3322 	LIST_FOREACH(pmap, &allpmaps, pm_list) {
3323 		pte1p = pmap_pte1(pmap, va);
3324 		pte1_store(pte1p, npte1);
3325 	}
3326 
3327 #ifdef SMP
3328 	/* Kill all the small mappings or the big one only. */
3329 	if (pte1_is_section(npte1))
3330 		tlb_flush_range(pte1_trunc(va), PTE1_SIZE);
3331 	else
3332 		tlb_flush(pte1_trunc(va));
3333 #endif
3334 }
3335 
3336 #ifdef SMP
3337 struct pte1_action {
3338 	vm_offset_t va;
3339 	pt1_entry_t npte1;
3340 	u_int update;		/* CPU that updates the PTE1 */
3341 };
3342 
3343 static void
3344 pmap_update_pte1_action(void *arg)
3345 {
3346 	struct pte1_action *act = arg;
3347 
3348 	if (act->update == PCPU_GET(cpuid))
3349 		pmap_update_pte1_kernel(act->va, act->npte1);
3350 }
3351 
3352 /*
3353  *  Change pte1 on current pmap.
3354  *  Note that kernel pte1 must be changed on all pmaps.
3355  *
3356  *  According to the architecture reference manual published by ARM,
3357  *  the behaviour is UNPREDICTABLE when two or more TLB entries map the same VA.
3358  *  According to this manual, UNPREDICTABLE behaviours must never happen in
3359  *  a viable system. In contrast, on x86 processors, it is not specified which
3360  *  TLB entry mapping the virtual address will be used, but the MMU doesn't
3361  *  generate a bogus translation the way it does on Cortex-A8 rev 2 (Beaglebone
3362  *  Black).
3363  *
3364  *  It's a problem when either promotion or demotion is being done. The pte1
3365  *  update and appropriate TLB flush must be done atomically in general.
3366  */
3367 static void
3368 pmap_change_pte1(pmap_t pmap, pt1_entry_t *pte1p, vm_offset_t va,
3369     pt1_entry_t npte1)
3370 {
3371 
3372 	if (pmap == kernel_pmap) {
3373 		struct pte1_action act;
3374 
3375 		sched_pin();
3376 		act.va = va;
3377 		act.npte1 = npte1;
3378 		act.update = PCPU_GET(cpuid);
3379 		smp_rendezvous_cpus(all_cpus, smp_no_rendezvous_barrier,
3380 		    pmap_update_pte1_action, NULL, &act);
3381 		sched_unpin();
3382 	} else {
3383 		register_t cspr;
3384 
3385 		/*
3386 		 * Use break-before-make approach for changing userland
3387 		 * mappings. It can cause L1 translation aborts on other
3388 		 * cores in SMP case. So, special treatment is implemented
3389 		 * in pmap_fault(). To reduce the likelihood that another core
3390 		 * will be affected by the broken mapping, disable interrupts
3391 		 * until the mapping change is completed.
3392 		 */
3393 		cspr = disable_interrupts(PSR_I | PSR_F);
3394 		pte1_clear(pte1p);
3395 		pmap_tlb_flush_pte1(pmap, va, npte1);
3396 		pte1_store(pte1p, npte1);
3397 		restore_interrupts(cspr);
3398 	}
3399 }
3400 #else
3401 static void
3402 pmap_change_pte1(pmap_t pmap, pt1_entry_t *pte1p, vm_offset_t va,
3403     pt1_entry_t npte1)
3404 {
3405 
3406 	if (pmap == kernel_pmap) {
3407 		mtx_lock_spin(&allpmaps_lock);
3408 		pmap_update_pte1_kernel(va, npte1);
3409 		mtx_unlock_spin(&allpmaps_lock);
3410 	} else {
3411 		register_t cspr;
3412 
3413 		/*
3414 		 * Use break-before-make approach for changing userland
3415 		 * mappings. It's absolutely safe in UP case when interrupts
3416 		 * are disabled.
3417 		 */
3418 		cspr = disable_interrupts(PSR_I | PSR_F);
3419 		pte1_clear(pte1p);
3420 		pmap_tlb_flush_pte1(pmap, va, npte1);
3421 		pte1_store(pte1p, npte1);
3422 		restore_interrupts(cspr);
3423 	}
3424 }
3425 #endif
3426 
3427 #if VM_NRESERVLEVEL > 0
3428 /*
3429  *  Tries to promote the NPTE2_IN_PT2, contiguous 4KB page mappings that are
3430  *  within a single page table page (PT2) to a single 1MB page mapping.
3431  *  For promotion to occur, two conditions must be met: (1) the 4KB page
3432  *  mappings must map aligned, contiguous physical memory and (2) the 4KB page
3433  *  mappings must have identical characteristics.
3434  *
3435  *  Managed (PG_MANAGED) mappings within the kernel address space are not
3436  *  promoted.  The reason is that kernel PTE1s are replicated in each pmap but
3437  *  pmap_remove_write(), pmap_clear_modify(), and pmap_clear_reference() only
3438  *  read the PTE1 from the kernel pmap.
3439  */
3440 static void
3441 pmap_promote_pte1(pmap_t pmap, pt1_entry_t *pte1p, vm_offset_t va)
3442 {
3443 	pt1_entry_t npte1;
3444 	pt2_entry_t *fpte2p, fpte2, fpte2_fav;
3445 	pt2_entry_t *pte2p, pte2;
3446 	vm_offset_t pteva __unused;
3447 	vm_page_t m __unused;
3448 
3449 	PDEBUG(6, printf("%s(%p): try for va %#x pte1 %#x at %p\n", __func__,
3450 	    pmap, va, pte1_load(pte1p), pte1p));
3451 
3452 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
3453 
3454 	/*
3455 	 * Examine the first PTE2 in the specified PT2. Abort if this PTE2 is
3456 	 * either invalid, unused, or does not map the first 4KB physical page
3457 	 * within a 1MB page.
3458 	 */
3459 	fpte2p = pmap_pte2_quick(pmap, pte1_trunc(va));
3460 	fpte2 = pte2_load(fpte2p);
3461 	if ((fpte2 & ((PTE2_FRAME & PTE1_OFFSET) | PTE2_A | PTE2_V)) !=
3462 	    (PTE2_A | PTE2_V)) {
3463 		pmap_pte1_p_failures++;
3464 		CTR3(KTR_PMAP, "%s: failure(1) for va %#x in pmap %p",
3465 		    __func__, va, pmap);
3466 		return;
3467 	}
3468 	if (pte2_is_managed(fpte2) && pmap == kernel_pmap) {
3469 		pmap_pte1_p_failures++;
3470 		CTR3(KTR_PMAP, "%s: failure(2) for va %#x in pmap %p",
3471 		    __func__, va, pmap);
3472 		return;
3473 	}
3474 	if ((fpte2 & (PTE2_NM | PTE2_RO)) == PTE2_NM) {
3475 		/*
3476 		 * When page is not modified, PTE2_RO can be set without
3477 		 * a TLB invalidation.
3478 		 */
3479 		fpte2 |= PTE2_RO;
3480 		pte2_store(fpte2p, fpte2);
3481 	}
3482 
3483 	/*
3484 	 * Examine each of the other PTE2s in the specified PT2. Abort if this
3485 	 * PTE2 maps an unexpected 4KB physical page or does not have identical
3486 	 * characteristics to the first PTE2.
3487 	 */
3488 	fpte2_fav = (fpte2 & (PTE2_FRAME | PTE2_A | PTE2_V));
3489 	fpte2_fav += PTE1_SIZE - PTE2_SIZE; /* examine from the end */
3490 	for (pte2p = fpte2p + NPTE2_IN_PT2 - 1; pte2p > fpte2p; pte2p--) {
3491 		pte2 = pte2_load(pte2p);
3492 		if ((pte2 & (PTE2_FRAME | PTE2_A | PTE2_V)) != fpte2_fav) {
3493 			pmap_pte1_p_failures++;
3494 			CTR3(KTR_PMAP, "%s: failure(3) for va %#x in pmap %p",
3495 			    __func__, va, pmap);
3496 			return;
3497 		}
3498 		if ((pte2 & (PTE2_NM | PTE2_RO)) == PTE2_NM) {
3499 			/*
3500 			 * When page is not modified, PTE2_RO can be set
3501 			 * without a TLB invalidation. See note above.
3502 			 */
3503 			pte2 |= PTE2_RO;
3504 			pte2_store(pte2p, pte2);
3505 			pteva = pte1_trunc(va) | (pte2 & PTE1_OFFSET &
3506 			    PTE2_FRAME);
3507 			CTR3(KTR_PMAP, "%s: protect for va %#x in pmap %p",
3508 			    __func__, pteva, pmap);
3509 		}
3510 		if ((pte2 & PTE2_PROMOTE) != (fpte2 & PTE2_PROMOTE)) {
3511 			pmap_pte1_p_failures++;
3512 			CTR3(KTR_PMAP, "%s: failure(4) for va %#x in pmap %p",
3513 			    __func__, va, pmap);
3514 			return;
3515 		}
3516 
3517 		fpte2_fav -= PTE2_SIZE;
3518 	}
3519 	/*
3520 	 * The page table page in its current state will stay in PT2TAB
3521 	 * until the PTE1 mapping the section is demoted by pmap_demote_pte1()
3522 	 * or destroyed by pmap_remove_pte1().
3523 	 *
3524 	 * Note that L2 page table size is not equal to PAGE_SIZE.
3525 	 */
3526 	m = PHYS_TO_VM_PAGE(trunc_page(pte1_link_pa(pte1_load(pte1p))));
3527 	KASSERT(m >= vm_page_array && m < &vm_page_array[vm_page_array_size],
3528 	    ("%s: PT2 page is out of range", __func__));
3529 	KASSERT(m->pindex == (pte1_index(va) & ~PT2PG_MASK),
3530 	    ("%s: PT2 page's pindex is wrong", __func__));
3531 
3532 	/*
3533 	 * Get pte1 from pte2 format.
3534 	 */
3535 	npte1 = (fpte2 & PTE1_FRAME) | ATTR_TO_L1(fpte2) | PTE1_V;
3536 
3537 	/*
3538 	 * Promote the pv entries.
3539 	 */
3540 	if (pte2_is_managed(fpte2))
3541 		pmap_pv_promote_pte1(pmap, va, pte1_pa(npte1));
3542 
3543 	/*
3544 	 * Promote the mappings.
3545 	 */
3546 	pmap_change_pte1(pmap, pte1p, va, npte1);
3547 
3548 	pmap_pte1_promotions++;
3549 	CTR3(KTR_PMAP, "%s: success for va %#x in pmap %p",
3550 	    __func__, va, pmap);
3551 
3552 	PDEBUG(6, printf("%s(%p): success for va %#x pte1 %#x(%#x) at %p\n",
3553 	    __func__, pmap, va, npte1, pte1_load(pte1p), pte1p));
3554 }
3555 #endif /* VM_NRESERVLEVEL > 0 */
3556 
3557 /*
3558  *  Zero L2 page table page.
3559  */
3560 static __inline void
3561 pmap_clear_pt2(pt2_entry_t *fpte2p)
3562 {
3563 	pt2_entry_t *pte2p;
3564 
3565 	for (pte2p = fpte2p; pte2p < fpte2p + NPTE2_IN_PT2; pte2p++)
3566 		pte2_clear(pte2p);
3567 
3568 }
3569 
3570 /*
3571  *  Removes a 1MB page mapping from the kernel pmap.
3572  */
3573 static void
3574 pmap_remove_kernel_pte1(pmap_t pmap, pt1_entry_t *pte1p, vm_offset_t va)
3575 {
3576 	vm_page_t m;
3577 	uint32_t pte1_idx;
3578 	pt2_entry_t *fpte2p;
3579 	vm_paddr_t pt2_pa;
3580 
3581 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
3582 	m = pmap_pt2_page(pmap, va);
3583 	if (m == NULL)
3584 		/*
3585 		 * QQQ: Is this function called only on promoted pte1?
3586 		 *      We certainly do section mappings directly
3587 		 *      (without promotion) in kernel !!!
3588 		 */
3589 		panic("%s: missing pt2 page", __func__);
3590 
3591 	pte1_idx = pte1_index(va);
3592 
3593 	/*
3594 	 * Initialize the L2 page table.
3595 	 */
3596 	fpte2p = page_pt2(pt2map_pt2pg(va), pte1_idx);
3597 	pmap_clear_pt2(fpte2p);
3598 
3599 	/*
3600 	 * Remove the mapping.
3601 	 */
3602 	pt2_pa = page_pt2pa(VM_PAGE_TO_PHYS(m), pte1_idx);
3603 	pmap_kenter_pte1(va, PTE1_LINK(pt2_pa));
3604 
3605 	/*
3606 	 * QQQ: We do not need to invalidate PT2MAP mapping
3607 	 * as we did not change it. I.e. the L2 page table page
3608 	 * was and still is mapped the same way.
3609 	 */
3610 }
3611 
3612 /*
3613  *  Do the things to unmap a section in a process
3614  */
3615 static void
3616 pmap_remove_pte1(pmap_t pmap, pt1_entry_t *pte1p, vm_offset_t sva,
3617     struct spglist *free)
3618 {
3619 	pt1_entry_t opte1;
3620 	struct md_page *pvh;
3621 	vm_offset_t eva, va;
3622 	vm_page_t m;
3623 
3624 	PDEBUG(6, printf("%s(%p): va %#x pte1 %#x at %p\n", __func__, pmap, sva,
3625 	    pte1_load(pte1p), pte1p));
3626 
3627 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
3628 	KASSERT((sva & PTE1_OFFSET) == 0,
3629 	    ("%s: sva is not 1mpage aligned", __func__));
3630 
3631 	/*
3632 	 * Clear and invalidate the mapping. It should occupy one and only TLB
3633 	 * entry. So, pmap_tlb_flush() called with aligned address should be
3634 	 * sufficient.
3635 	 */
3636 	opte1 = pte1_load_clear(pte1p);
3637 	pmap_tlb_flush(pmap, sva);
3638 
3639 	if (pte1_is_wired(opte1))
3640 		pmap->pm_stats.wired_count -= PTE1_SIZE / PAGE_SIZE;
3641 	pmap->pm_stats.resident_count -= PTE1_SIZE / PAGE_SIZE;
3642 	if (pte1_is_managed(opte1)) {
3643 		pvh = pa_to_pvh(pte1_pa(opte1));
3644 		pmap_pvh_free(pvh, pmap, sva);
3645 		eva = sva + PTE1_SIZE;
3646 		for (va = sva, m = PHYS_TO_VM_PAGE(pte1_pa(opte1));
3647 		    va < eva; va += PAGE_SIZE, m++) {
3648 			if (pte1_is_dirty(opte1))
3649 				vm_page_dirty(m);
3650 			if (opte1 & PTE1_A)
3651 				vm_page_aflag_set(m, PGA_REFERENCED);
3652 			if (TAILQ_EMPTY(&m->md.pv_list) &&
3653 			    TAILQ_EMPTY(&pvh->pv_list))
3654 				vm_page_aflag_clear(m, PGA_WRITEABLE);
3655 		}
3656 	}
3657 	if (pmap == kernel_pmap) {
3658 		/*
3659 		 * L2 page table(s) can't be removed from kernel map as
3660 		 * kernel counts on it (stuff around pmap_growkernel()).
3661 		 */
3662 		 pmap_remove_kernel_pte1(pmap, pte1p, sva);
3663 	} else {
3664 		/*
3665 		 * Get associated L2 page table page.
3666 		 * It's possible that the page was never allocated.
3667 		 */
3668 		m = pmap_pt2_page(pmap, sva);
3669 		if (m != NULL)
3670 			pmap_unwire_pt2_all(pmap, sva, m, free);
3671 	}
3672 }
3673 
3674 /*
3675  *  Fills L2 page table page with mappings to consecutive physical pages.
3676  */
3677 static __inline void
3678 pmap_fill_pt2(pt2_entry_t *fpte2p, pt2_entry_t npte2)
3679 {
3680 	pt2_entry_t *pte2p;
3681 
3682 	for (pte2p = fpte2p; pte2p < fpte2p + NPTE2_IN_PT2; pte2p++) {
3683 		pte2_store(pte2p, npte2);
3684 		npte2 += PTE2_SIZE;
3685 	}
3686 }
3687 
3688 /*
3689  *  Tries to demote a 1MB page mapping. If demotion fails, the
3690  *  1MB page mapping is invalidated.
3691  */
3692 static boolean_t
3693 pmap_demote_pte1(pmap_t pmap, pt1_entry_t *pte1p, vm_offset_t va)
3694 {
3695 	pt1_entry_t opte1, npte1;
3696 	pt2_entry_t *fpte2p, npte2;
3697 	vm_paddr_t pt2pg_pa, pt2_pa;
3698 	vm_page_t m;
3699 	struct spglist free;
3700 	uint32_t pte1_idx, isnew = 0;
3701 
3702 	PDEBUG(6, printf("%s(%p): try for va %#x pte1 %#x at %p\n", __func__,
3703 	    pmap, va, pte1_load(pte1p), pte1p));
3704 
3705 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
3706 
3707 	opte1 = pte1_load(pte1p);
3708 	KASSERT(pte1_is_section(opte1), ("%s: opte1 not a section", __func__));
3709 
3710 	if ((opte1 & PTE1_A) == 0 || (m = pmap_pt2_page(pmap, va)) == NULL) {
3711 		KASSERT(!pte1_is_wired(opte1),
3712 		    ("%s: PT2 page for a wired mapping is missing", __func__));
3713 
3714 		/*
3715 		 * Invalidate the 1MB page mapping and return
3716 		 * "failure" if the mapping was never accessed or the
3717 		 * allocation of the new page table page fails.
3718 		 */
3719 		if ((opte1 & PTE1_A) == 0 || (m = vm_page_alloc(NULL,
3720 		    pte1_index(va) & ~PT2PG_MASK, VM_ALLOC_NOOBJ |
3721 		    VM_ALLOC_NORMAL | VM_ALLOC_WIRED)) == NULL) {
3722 			SLIST_INIT(&free);
3723 			pmap_remove_pte1(pmap, pte1p, pte1_trunc(va), &free);
3724 			vm_page_free_pages_toq(&free, false);
3725 			CTR3(KTR_PMAP, "%s: failure for va %#x in pmap %p",
3726 			    __func__, va, pmap);
3727 			return (FALSE);
3728 		}
3729 		if (va < VM_MAXUSER_ADDRESS)
3730 			pmap->pm_stats.resident_count++;
3731 
3732 		isnew = 1;
3733 
3734 		/*
3735 		 * We init all L2 page tables in the page even if
3736 		 * we are going to change everything for one L2 page
3737 		 * table in a while.
3738 		 */
3739 		pt2pg_pa = pmap_pt2pg_init(pmap, va, m);
3740 	} else {
3741 		if (va < VM_MAXUSER_ADDRESS) {
3742 			if (pt2_is_empty(m, va))
3743 				isnew = 1; /* Demoting section w/o promotion. */
3744 #ifdef INVARIANTS
3745 			else
3746 				KASSERT(pt2_is_full(m, va), ("%s: bad PT2 wire"
3747 				    " count %u", __func__,
3748 				    pt2_wirecount_get(m, pte1_index(va))));
3749 #endif
3750 		}
3751 	}
3752 
3753 	pt2pg_pa = VM_PAGE_TO_PHYS(m);
3754 	pte1_idx = pte1_index(va);
3755 	/*
3756 	 * If the pmap is current, then the PT2MAP can provide access to
3757 	 * the page table page (promoted L2 page tables are not unmapped).
3758 	 * Otherwise, temporarily map the L2 page table page (m) into
3759 	 * the kernel's address space at either PADDR1 or PADDR2.
3760 	 *
3761 	 * Note that L2 page table size is not equal to PAGE_SIZE.
3762 	 */
3763 	if (pmap_is_current(pmap))
3764 		fpte2p = page_pt2(pt2map_pt2pg(va), pte1_idx);
3765 	else if (curthread->td_pinned > 0 && rw_wowned(&pvh_global_lock)) {
3766 		if (pte2_pa(pte2_load(PMAP1)) != pt2pg_pa) {
3767 			pte2_store(PMAP1, PTE2_KPT(pt2pg_pa));
3768 #ifdef SMP
3769 			PMAP1cpu = PCPU_GET(cpuid);
3770 #endif
3771 			tlb_flush_local((vm_offset_t)PADDR1);
3772 			PMAP1changed++;
3773 		} else
3774 #ifdef SMP
3775 		if (PMAP1cpu != PCPU_GET(cpuid)) {
3776 			PMAP1cpu = PCPU_GET(cpuid);
3777 			tlb_flush_local((vm_offset_t)PADDR1);
3778 			PMAP1changedcpu++;
3779 		} else
3780 #endif
3781 			PMAP1unchanged++;
3782 		fpte2p = page_pt2((vm_offset_t)PADDR1, pte1_idx);
3783 	} else {
3784 		mtx_lock(&PMAP2mutex);
3785 		if (pte2_pa(pte2_load(PMAP2)) != pt2pg_pa) {
3786 			pte2_store(PMAP2, PTE2_KPT(pt2pg_pa));
3787 			tlb_flush((vm_offset_t)PADDR2);
3788 		}
3789 		fpte2p = page_pt2((vm_offset_t)PADDR2, pte1_idx);
3790 	}
3791 	pt2_pa = page_pt2pa(pt2pg_pa, pte1_idx);
3792 	npte1 = PTE1_LINK(pt2_pa);
3793 
3794 	KASSERT((opte1 & PTE1_A) != 0,
3795 	    ("%s: opte1 is missing PTE1_A", __func__));
3796 	KASSERT((opte1 & (PTE1_NM | PTE1_RO)) != PTE1_NM,
3797 	    ("%s: opte1 has PTE1_NM", __func__));
3798 
3799 	/*
3800 	 *  Get pte2 from pte1 format.
3801 	*/
3802 	npte2 = pte1_pa(opte1) | ATTR_TO_L2(opte1) | PTE2_V;
3803 
3804 	/*
3805 	 * If the L2 page table page is new, initialize it. If the mapping
3806 	 * has changed attributes, update the page table entries.
3807 	 */
3808 	if (isnew != 0) {
3809 		pt2_wirecount_set(m, pte1_idx, NPTE2_IN_PT2);
3810 		pmap_fill_pt2(fpte2p, npte2);
3811 	} else if ((pte2_load(fpte2p) & PTE2_PROMOTE) !=
3812 		    (npte2 & PTE2_PROMOTE))
3813 		pmap_fill_pt2(fpte2p, npte2);
3814 
3815 	KASSERT(pte2_pa(pte2_load(fpte2p)) == pte2_pa(npte2),
3816 	    ("%s: fpte2p and npte2 map different physical addresses",
3817 	    __func__));
3818 
3819 	if (fpte2p == PADDR2)
3820 		mtx_unlock(&PMAP2mutex);
3821 
3822 	/*
3823 	 * Demote the mapping. This pmap is locked. The old PTE1 has
3824 	 * PTE1_A set. If the old PTE1 has not PTE1_RO set, it also
3825 	 * has not PTE1_NM set. Thus, there is no danger of a race with
3826 	 * another processor changing the setting of PTE1_A and/or PTE1_NM
3827 	 * between the read above and the store below.
3828 	 */
3829 	pmap_change_pte1(pmap, pte1p, va, npte1);
3830 
3831 	/*
3832 	 * Demote the pv entry. This depends on the earlier demotion
3833 	 * of the mapping. Specifically, the (re)creation of a per-
3834 	 * page pv entry might trigger the execution of pmap_pv_reclaim(),
3835 	 * which might reclaim a newly (re)created per-page pv entry
3836 	 * and destroy the associated mapping. In order to destroy
3837 	 * the mapping, the PTE1 must have already changed from mapping
3838 	 * the 1mpage to referencing the page table page.
3839 	 */
3840 	if (pte1_is_managed(opte1))
3841 		pmap_pv_demote_pte1(pmap, va, pte1_pa(opte1));
3842 
3843 	pmap_pte1_demotions++;
3844 	CTR3(KTR_PMAP, "%s: success for va %#x in pmap %p",
3845 	    __func__, va, pmap);
3846 
3847 	PDEBUG(6, printf("%s(%p): success for va %#x pte1 %#x(%#x) at %p\n",
3848 	    __func__, pmap, va, npte1, pte1_load(pte1p), pte1p));
3849 	return (TRUE);
3850 }
3851 
3852 /*
3853  *	Insert the given physical page (p) at
3854  *	the specified virtual address (v) in the
3855  *	target physical map with the protection requested.
3856  *
3857  *	If specified, the page will be wired down, meaning
3858  *	that the related pte can not be reclaimed.
3859  *
3860  *	NB:  This is the only routine which MAY NOT lazy-evaluate
3861  *	or lose information.  That is, this routine must actually
3862  *	insert this page into the given map NOW.
3863  */
3864 int
3865 pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot,
3866     u_int flags, int8_t psind)
3867 {
3868 	pt1_entry_t *pte1p;
3869 	pt2_entry_t *pte2p;
3870 	pt2_entry_t npte2, opte2;
3871 	pv_entry_t pv;
3872 	vm_paddr_t opa, pa;
3873 	vm_page_t mpte2, om;
3874 	int rv;
3875 
3876 	va = trunc_page(va);
3877 	KASSERT(va <= vm_max_kernel_address, ("%s: toobig", __func__));
3878 	KASSERT(va < UPT2V_MIN_ADDRESS || va >= UPT2V_MAX_ADDRESS,
3879 	    ("%s: invalid to pmap_enter page table pages (va: 0x%x)", __func__,
3880 	    va));
3881 	KASSERT((m->oflags & VPO_UNMANAGED) != 0 || va < kmi.clean_sva ||
3882 	    va >= kmi.clean_eva,
3883 	    ("%s: managed mapping within the clean submap", __func__));
3884 	if ((m->oflags & VPO_UNMANAGED) == 0 && !vm_page_xbusied(m))
3885 		VM_OBJECT_ASSERT_LOCKED(m->object);
3886 	KASSERT((flags & PMAP_ENTER_RESERVED) == 0,
3887 	    ("%s: flags %u has reserved bits set", __func__, flags));
3888 	pa = VM_PAGE_TO_PHYS(m);
3889 	npte2 = PTE2(pa, PTE2_A, vm_page_pte2_attr(m));
3890 	if ((flags & VM_PROT_WRITE) == 0)
3891 		npte2 |= PTE2_NM;
3892 	if ((prot & VM_PROT_WRITE) == 0)
3893 		npte2 |= PTE2_RO;
3894 	KASSERT((npte2 & (PTE2_NM | PTE2_RO)) != PTE2_RO,
3895 	    ("%s: flags includes VM_PROT_WRITE but prot doesn't", __func__));
3896 	if ((prot & VM_PROT_EXECUTE) == 0)
3897 		npte2 |= PTE2_NX;
3898 	if ((flags & PMAP_ENTER_WIRED) != 0)
3899 		npte2 |= PTE2_W;
3900 	if (va < VM_MAXUSER_ADDRESS)
3901 		npte2 |= PTE2_U;
3902 	if (pmap != kernel_pmap)
3903 		npte2 |= PTE2_NG;
3904 
3905 	rw_wlock(&pvh_global_lock);
3906 	PMAP_LOCK(pmap);
3907 	sched_pin();
3908 	if (psind == 1) {
3909 		/* Assert the required virtual and physical alignment. */
3910 		KASSERT((va & PTE1_OFFSET) == 0,
3911 		    ("%s: va unaligned", __func__));
3912 		KASSERT(m->psind > 0, ("%s: m->psind < psind", __func__));
3913 		rv = pmap_enter_pte1(pmap, va, PTE1_PA(pa) | ATTR_TO_L1(npte2) |
3914 		    PTE1_V, flags, m);
3915 		goto out;
3916 	}
3917 
3918 	/*
3919 	 * In the case that a page table page is not
3920 	 * resident, we are creating it here.
3921 	 */
3922 	if (va < VM_MAXUSER_ADDRESS) {
3923 		mpte2 = pmap_allocpte2(pmap, va, flags);
3924 		if (mpte2 == NULL) {
3925 			KASSERT((flags & PMAP_ENTER_NOSLEEP) != 0,
3926 			    ("pmap_allocpte2 failed with sleep allowed"));
3927 			rv = KERN_RESOURCE_SHORTAGE;
3928 			goto out;
3929 		}
3930 	} else
3931 		mpte2 = NULL;
3932 	pte1p = pmap_pte1(pmap, va);
3933 	if (pte1_is_section(pte1_load(pte1p)))
3934 		panic("%s: attempted on 1MB page", __func__);
3935 	pte2p = pmap_pte2_quick(pmap, va);
3936 	if (pte2p == NULL)
3937 		panic("%s: invalid L1 page table entry va=%#x", __func__, va);
3938 
3939 	om = NULL;
3940 	opte2 = pte2_load(pte2p);
3941 	opa = pte2_pa(opte2);
3942 	/*
3943 	 * Mapping has not changed, must be protection or wiring change.
3944 	 */
3945 	if (pte2_is_valid(opte2) && (opa == pa)) {
3946 		/*
3947 		 * Wiring change, just update stats. We don't worry about
3948 		 * wiring PT2 pages as they remain resident as long as there
3949 		 * are valid mappings in them. Hence, if a user page is wired,
3950 		 * the PT2 page will be also.
3951 		 */
3952 		if (pte2_is_wired(npte2) && !pte2_is_wired(opte2))
3953 			pmap->pm_stats.wired_count++;
3954 		else if (!pte2_is_wired(npte2) && pte2_is_wired(opte2))
3955 			pmap->pm_stats.wired_count--;
3956 
3957 		/*
3958 		 * Remove extra pte2 reference
3959 		 */
3960 		if (mpte2)
3961 			pt2_wirecount_dec(mpte2, pte1_index(va));
3962 		if ((m->oflags & VPO_UNMANAGED) == 0)
3963 			om = m;
3964 		goto validate;
3965 	}
3966 
3967 	/*
3968 	 * QQQ: We think that changing physical address on writeable mapping
3969 	 *      is not safe. Well, maybe on kernel address space with correct
3970 	 *      locking, it can make a sense. However, we have no idea why
3971 	 *      anyone should do that on user address space. Are we wrong?
3972 	 */
3973 	KASSERT((opa == 0) || (opa == pa) ||
3974 	    !pte2_is_valid(opte2) || ((opte2 & PTE2_RO) != 0),
3975 	    ("%s: pmap %p va %#x(%#x) opa %#x pa %#x - gotcha %#x %#x!",
3976 	    __func__, pmap, va, opte2, opa, pa, flags, prot));
3977 
3978 	pv = NULL;
3979 
3980 	/*
3981 	 * Mapping has changed, invalidate old range and fall through to
3982 	 * handle validating new mapping.
3983 	 */
3984 	if (opa) {
3985 		if (pte2_is_wired(opte2))
3986 			pmap->pm_stats.wired_count--;
3987 		om = PHYS_TO_VM_PAGE(opa);
3988 		if (om != NULL && (om->oflags & VPO_UNMANAGED) != 0)
3989 			om = NULL;
3990 		if (om != NULL)
3991 			pv = pmap_pvh_remove(&om->md, pmap, va);
3992 
3993 		/*
3994 		 * Remove extra pte2 reference
3995 		 */
3996 		if (mpte2 != NULL)
3997 			pt2_wirecount_dec(mpte2, va >> PTE1_SHIFT);
3998 	} else
3999 		pmap->pm_stats.resident_count++;
4000 
4001 	/*
4002 	 * Enter on the PV list if part of our managed memory.
4003 	 */
4004 	if ((m->oflags & VPO_UNMANAGED) == 0) {
4005 		if (pv == NULL) {
4006 			pv = get_pv_entry(pmap, FALSE);
4007 			pv->pv_va = va;
4008 		}
4009 		TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_next);
4010 	} else if (pv != NULL)
4011 		free_pv_entry(pmap, pv);
4012 
4013 	/*
4014 	 * Increment counters
4015 	 */
4016 	if (pte2_is_wired(npte2))
4017 		pmap->pm_stats.wired_count++;
4018 
4019 validate:
4020 	/*
4021 	 * Now validate mapping with desired protection/wiring.
4022 	 */
4023 	if (prot & VM_PROT_WRITE) {
4024 		if ((m->oflags & VPO_UNMANAGED) == 0)
4025 			vm_page_aflag_set(m, PGA_WRITEABLE);
4026 	}
4027 
4028 	/*
4029 	 * If the mapping or permission bits are different, we need
4030 	 * to update the pte2.
4031 	 *
4032 	 * QQQ: Think again and again what to do
4033 	 *      if the mapping is going to be changed!
4034 	 */
4035 	if ((opte2 & ~(PTE2_NM | PTE2_A)) != (npte2 & ~(PTE2_NM | PTE2_A))) {
4036 		/*
4037 		 * Sync icache if exec permission and attribute VM_MEMATTR_WB_WA
4038 		 * is set. Do it now, before the mapping is stored and made
4039 		 * valid for hardware table walk. If done later, there is a race
4040 		 * for other threads of current process in lazy loading case.
4041 		 * Don't do it for kernel memory which is mapped with exec
4042 		 * permission even if the memory isn't going to hold executable
4043 		 * code. The only time when icache sync is needed is after
4044 		 * kernel module is loaded and the relocation info is processed.
4045 		 * And it's done in elf_cpu_load_file().
4046 		 *
4047 		 * QQQ: (1) Does it exist any better way where
4048 		 *          or how to sync icache?
4049 		 *      (2) Now, we do it on a page basis.
4050 		 */
4051 		if ((prot & VM_PROT_EXECUTE) && pmap != kernel_pmap &&
4052 		    m->md.pat_mode == VM_MEMATTR_WB_WA &&
4053 		    (opa != pa || (opte2 & PTE2_NX)))
4054 			cache_icache_sync_fresh(va, pa, PAGE_SIZE);
4055 
4056 		if (opte2 & PTE2_V) {
4057 			/* Change mapping with break-before-make approach. */
4058 			opte2 = pte2_load_clear(pte2p);
4059 			pmap_tlb_flush(pmap, va);
4060 			pte2_store(pte2p, npte2);
4061 			if (om != NULL) {
4062 				KASSERT((om->oflags & VPO_UNMANAGED) == 0,
4063 				    ("%s: om %p unmanaged", __func__, om));
4064 				if ((opte2 & PTE2_A) != 0)
4065 					vm_page_aflag_set(om, PGA_REFERENCED);
4066 				if (pte2_is_dirty(opte2))
4067 					vm_page_dirty(om);
4068 				if (TAILQ_EMPTY(&om->md.pv_list) &&
4069 				    ((om->flags & PG_FICTITIOUS) != 0 ||
4070 				    TAILQ_EMPTY(&pa_to_pvh(opa)->pv_list)))
4071 					vm_page_aflag_clear(om, PGA_WRITEABLE);
4072 			}
4073 		} else
4074 			pte2_store(pte2p, npte2);
4075 	}
4076 #if 0
4077 	else {
4078 		/*
4079 		 * QQQ: In time when both access and not mofified bits are
4080 		 *      emulated by software, this should not happen. Some
4081 		 *      analysis is need, if this really happen. Missing
4082 		 *      tlb flush somewhere could be the reason.
4083 		 */
4084 		panic("%s: pmap %p va %#x opte2 %x npte2 %x !!", __func__, pmap,
4085 		    va, opte2, npte2);
4086 	}
4087 #endif
4088 
4089 #if VM_NRESERVLEVEL > 0
4090 	/*
4091 	 * If both the L2 page table page and the reservation are fully
4092 	 * populated, then attempt promotion.
4093 	 */
4094 	if ((mpte2 == NULL || pt2_is_full(mpte2, va)) &&
4095 	    sp_enabled && (m->flags & PG_FICTITIOUS) == 0 &&
4096 	    vm_reserv_level_iffullpop(m) == 0)
4097 		pmap_promote_pte1(pmap, pte1p, va);
4098 #endif
4099 
4100 	rv = KERN_SUCCESS;
4101 out:
4102 	sched_unpin();
4103 	rw_wunlock(&pvh_global_lock);
4104 	PMAP_UNLOCK(pmap);
4105 	return (rv);
4106 }
4107 
4108 /*
4109  *  Do the things to unmap a page in a process.
4110  */
4111 static int
4112 pmap_remove_pte2(pmap_t pmap, pt2_entry_t *pte2p, vm_offset_t va,
4113     struct spglist *free)
4114 {
4115 	pt2_entry_t opte2;
4116 	vm_page_t m;
4117 
4118 	rw_assert(&pvh_global_lock, RA_WLOCKED);
4119 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4120 
4121 	/* Clear and invalidate the mapping. */
4122 	opte2 = pte2_load_clear(pte2p);
4123 	pmap_tlb_flush(pmap, va);
4124 
4125 	KASSERT(pte2_is_valid(opte2), ("%s: pmap %p va %#x not link pte2 %#x",
4126 	    __func__, pmap, va, opte2));
4127 
4128 	if (opte2 & PTE2_W)
4129 		pmap->pm_stats.wired_count -= 1;
4130 	pmap->pm_stats.resident_count -= 1;
4131 	if (pte2_is_managed(opte2)) {
4132 		m = PHYS_TO_VM_PAGE(pte2_pa(opte2));
4133 		if (pte2_is_dirty(opte2))
4134 			vm_page_dirty(m);
4135 		if (opte2 & PTE2_A)
4136 			vm_page_aflag_set(m, PGA_REFERENCED);
4137 		pmap_remove_entry(pmap, m, va);
4138 	}
4139 	return (pmap_unuse_pt2(pmap, va, free));
4140 }
4141 
4142 /*
4143  *  Remove a single page from a process address space.
4144  */
4145 static void
4146 pmap_remove_page(pmap_t pmap, vm_offset_t va, struct spglist *free)
4147 {
4148 	pt2_entry_t *pte2p;
4149 
4150 	rw_assert(&pvh_global_lock, RA_WLOCKED);
4151 	KASSERT(curthread->td_pinned > 0,
4152 	    ("%s: curthread not pinned", __func__));
4153 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4154 	if ((pte2p = pmap_pte2_quick(pmap, va)) == NULL ||
4155 	    !pte2_is_valid(pte2_load(pte2p)))
4156 		return;
4157 	pmap_remove_pte2(pmap, pte2p, va, free);
4158 }
4159 
4160 /*
4161  *  Remove the given range of addresses from the specified map.
4162  *
4163  *  It is assumed that the start and end are properly
4164  *  rounded to the page size.
4165  */
4166 void
4167 pmap_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
4168 {
4169 	vm_offset_t nextva;
4170 	pt1_entry_t *pte1p, pte1;
4171 	pt2_entry_t *pte2p, pte2;
4172 	struct spglist free;
4173 
4174 	/*
4175 	 * Perform an unsynchronized read. This is, however, safe.
4176 	 */
4177 	if (pmap->pm_stats.resident_count == 0)
4178 		return;
4179 
4180 	SLIST_INIT(&free);
4181 
4182 	rw_wlock(&pvh_global_lock);
4183 	sched_pin();
4184 	PMAP_LOCK(pmap);
4185 
4186 	/*
4187 	 * Special handling of removing one page. A very common
4188 	 * operation and easy to short circuit some code.
4189 	 */
4190 	if (sva + PAGE_SIZE == eva) {
4191 		pte1 = pte1_load(pmap_pte1(pmap, sva));
4192 		if (pte1_is_link(pte1)) {
4193 			pmap_remove_page(pmap, sva, &free);
4194 			goto out;
4195 		}
4196 	}
4197 
4198 	for (; sva < eva; sva = nextva) {
4199 		/*
4200 		 * Calculate address for next L2 page table.
4201 		 */
4202 		nextva = pte1_trunc(sva + PTE1_SIZE);
4203 		if (nextva < sva)
4204 			nextva = eva;
4205 		if (pmap->pm_stats.resident_count == 0)
4206 			break;
4207 
4208 		pte1p = pmap_pte1(pmap, sva);
4209 		pte1 = pte1_load(pte1p);
4210 
4211 		/*
4212 		 * Weed out invalid mappings. Note: we assume that the L1 page
4213 		 * table is always allocated, and in kernel virtual.
4214 		 */
4215 		if (pte1 == 0)
4216 			continue;
4217 
4218 		if (pte1_is_section(pte1)) {
4219 			/*
4220 			 * Are we removing the entire large page?  If not,
4221 			 * demote the mapping and fall through.
4222 			 */
4223 			if (sva + PTE1_SIZE == nextva && eva >= nextva) {
4224 				pmap_remove_pte1(pmap, pte1p, sva, &free);
4225 				continue;
4226 			} else if (!pmap_demote_pte1(pmap, pte1p, sva)) {
4227 				/* The large page mapping was destroyed. */
4228 				continue;
4229 			}
4230 #ifdef INVARIANTS
4231 			else {
4232 				/* Update pte1 after demotion. */
4233 				pte1 = pte1_load(pte1p);
4234 			}
4235 #endif
4236 		}
4237 
4238 		KASSERT(pte1_is_link(pte1), ("%s: pmap %p va %#x pte1 %#x at %p"
4239 		    " is not link", __func__, pmap, sva, pte1, pte1p));
4240 
4241 		/*
4242 		 * Limit our scan to either the end of the va represented
4243 		 * by the current L2 page table page, or to the end of the
4244 		 * range being removed.
4245 		 */
4246 		if (nextva > eva)
4247 			nextva = eva;
4248 
4249 		for (pte2p = pmap_pte2_quick(pmap, sva); sva != nextva;
4250 		    pte2p++, sva += PAGE_SIZE) {
4251 			pte2 = pte2_load(pte2p);
4252 			if (!pte2_is_valid(pte2))
4253 				continue;
4254 			if (pmap_remove_pte2(pmap, pte2p, sva, &free))
4255 				break;
4256 		}
4257 	}
4258 out:
4259 	sched_unpin();
4260 	rw_wunlock(&pvh_global_lock);
4261 	PMAP_UNLOCK(pmap);
4262 	vm_page_free_pages_toq(&free, false);
4263 }
4264 
4265 /*
4266  *	Routine:	pmap_remove_all
4267  *	Function:
4268  *		Removes this physical page from
4269  *		all physical maps in which it resides.
4270  *		Reflects back modify bits to the pager.
4271  *
4272  *	Notes:
4273  *		Original versions of this routine were very
4274  *		inefficient because they iteratively called
4275  *		pmap_remove (slow...)
4276  */
4277 
4278 void
4279 pmap_remove_all(vm_page_t m)
4280 {
4281 	struct md_page *pvh;
4282 	pv_entry_t pv;
4283 	pmap_t pmap;
4284 	pt2_entry_t *pte2p, opte2;
4285 	pt1_entry_t *pte1p;
4286 	vm_offset_t va;
4287 	struct spglist free;
4288 
4289 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
4290 	    ("%s: page %p is not managed", __func__, m));
4291 	SLIST_INIT(&free);
4292 	rw_wlock(&pvh_global_lock);
4293 	sched_pin();
4294 	if ((m->flags & PG_FICTITIOUS) != 0)
4295 		goto small_mappings;
4296 	pvh = pa_to_pvh(VM_PAGE_TO_PHYS(m));
4297 	while ((pv = TAILQ_FIRST(&pvh->pv_list)) != NULL) {
4298 		va = pv->pv_va;
4299 		pmap = PV_PMAP(pv);
4300 		PMAP_LOCK(pmap);
4301 		pte1p = pmap_pte1(pmap, va);
4302 		(void)pmap_demote_pte1(pmap, pte1p, va);
4303 		PMAP_UNLOCK(pmap);
4304 	}
4305 small_mappings:
4306 	while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) {
4307 		pmap = PV_PMAP(pv);
4308 		PMAP_LOCK(pmap);
4309 		pmap->pm_stats.resident_count--;
4310 		pte1p = pmap_pte1(pmap, pv->pv_va);
4311 		KASSERT(!pte1_is_section(pte1_load(pte1p)), ("%s: found "
4312 		    "a 1mpage in page %p's pv list", __func__, m));
4313 		pte2p = pmap_pte2_quick(pmap, pv->pv_va);
4314 		opte2 = pte2_load_clear(pte2p);
4315 		pmap_tlb_flush(pmap, pv->pv_va);
4316 		KASSERT(pte2_is_valid(opte2), ("%s: pmap %p va %x zero pte2",
4317 		    __func__, pmap, pv->pv_va));
4318 		if (pte2_is_wired(opte2))
4319 			pmap->pm_stats.wired_count--;
4320 		if (opte2 & PTE2_A)
4321 			vm_page_aflag_set(m, PGA_REFERENCED);
4322 
4323 		/*
4324 		 * Update the vm_page_t clean and reference bits.
4325 		 */
4326 		if (pte2_is_dirty(opte2))
4327 			vm_page_dirty(m);
4328 		pmap_unuse_pt2(pmap, pv->pv_va, &free);
4329 		TAILQ_REMOVE(&m->md.pv_list, pv, pv_next);
4330 		free_pv_entry(pmap, pv);
4331 		PMAP_UNLOCK(pmap);
4332 	}
4333 	vm_page_aflag_clear(m, PGA_WRITEABLE);
4334 	sched_unpin();
4335 	rw_wunlock(&pvh_global_lock);
4336 	vm_page_free_pages_toq(&free, false);
4337 }
4338 
4339 /*
4340  *  Just subroutine for pmap_remove_pages() to reasonably satisfy
4341  *  good coding style, a.k.a. 80 character line width limit hell.
4342  */
4343 static __inline void
4344 pmap_remove_pte1_quick(pmap_t pmap, pt1_entry_t pte1, pv_entry_t pv,
4345     struct spglist *free)
4346 {
4347 	vm_paddr_t pa;
4348 	vm_page_t m, mt, mpt2pg;
4349 	struct md_page *pvh;
4350 
4351 	pa = pte1_pa(pte1);
4352 	m = PHYS_TO_VM_PAGE(pa);
4353 
4354 	KASSERT(m->phys_addr == pa, ("%s: vm_page_t %p addr mismatch %#x %#x",
4355 	    __func__, m, m->phys_addr, pa));
4356 	KASSERT((m->flags & PG_FICTITIOUS) != 0 ||
4357 	    m < &vm_page_array[vm_page_array_size],
4358 	    ("%s: bad pte1 %#x", __func__, pte1));
4359 
4360 	if (pte1_is_dirty(pte1)) {
4361 		for (mt = m; mt < &m[PTE1_SIZE / PAGE_SIZE]; mt++)
4362 			vm_page_dirty(mt);
4363 	}
4364 
4365 	pmap->pm_stats.resident_count -= PTE1_SIZE / PAGE_SIZE;
4366 	pvh = pa_to_pvh(pa);
4367 	TAILQ_REMOVE(&pvh->pv_list, pv, pv_next);
4368 	if (TAILQ_EMPTY(&pvh->pv_list)) {
4369 		for (mt = m; mt < &m[PTE1_SIZE / PAGE_SIZE]; mt++)
4370 			if (TAILQ_EMPTY(&mt->md.pv_list))
4371 				vm_page_aflag_clear(mt, PGA_WRITEABLE);
4372 	}
4373 	mpt2pg = pmap_pt2_page(pmap, pv->pv_va);
4374 	if (mpt2pg != NULL)
4375 		pmap_unwire_pt2_all(pmap, pv->pv_va, mpt2pg, free);
4376 }
4377 
4378 /*
4379  *  Just subroutine for pmap_remove_pages() to reasonably satisfy
4380  *  good coding style, a.k.a. 80 character line width limit hell.
4381  */
4382 static __inline void
4383 pmap_remove_pte2_quick(pmap_t pmap, pt2_entry_t pte2, pv_entry_t pv,
4384     struct spglist *free)
4385 {
4386 	vm_paddr_t pa;
4387 	vm_page_t m;
4388 	struct md_page *pvh;
4389 
4390 	pa = pte2_pa(pte2);
4391 	m = PHYS_TO_VM_PAGE(pa);
4392 
4393 	KASSERT(m->phys_addr == pa, ("%s: vm_page_t %p addr mismatch %#x %#x",
4394 	    __func__, m, m->phys_addr, pa));
4395 	KASSERT((m->flags & PG_FICTITIOUS) != 0 ||
4396 	    m < &vm_page_array[vm_page_array_size],
4397 	    ("%s: bad pte2 %#x", __func__, pte2));
4398 
4399 	if (pte2_is_dirty(pte2))
4400 		vm_page_dirty(m);
4401 
4402 	pmap->pm_stats.resident_count--;
4403 	TAILQ_REMOVE(&m->md.pv_list, pv, pv_next);
4404 	if (TAILQ_EMPTY(&m->md.pv_list) && (m->flags & PG_FICTITIOUS) == 0) {
4405 		pvh = pa_to_pvh(pa);
4406 		if (TAILQ_EMPTY(&pvh->pv_list))
4407 			vm_page_aflag_clear(m, PGA_WRITEABLE);
4408 	}
4409 	pmap_unuse_pt2(pmap, pv->pv_va, free);
4410 }
4411 
4412 /*
4413  *  Remove all pages from specified address space this aids process
4414  *  exit speeds. Also, this code is special cased for current process
4415  *  only, but can have the more generic (and slightly slower) mode enabled.
4416  *  This is much faster than pmap_remove in the case of running down
4417  *  an entire address space.
4418  */
4419 void
4420 pmap_remove_pages(pmap_t pmap)
4421 {
4422 	pt1_entry_t *pte1p, pte1;
4423 	pt2_entry_t *pte2p, pte2;
4424 	pv_entry_t pv;
4425 	struct pv_chunk *pc, *npc;
4426 	struct spglist free;
4427 	int field, idx;
4428 	int32_t bit;
4429 	uint32_t inuse, bitmask;
4430 	boolean_t allfree;
4431 
4432 	/*
4433 	 * Assert that the given pmap is only active on the current
4434 	 * CPU.  Unfortunately, we cannot block another CPU from
4435 	 * activating the pmap while this function is executing.
4436 	 */
4437 	KASSERT(pmap == vmspace_pmap(curthread->td_proc->p_vmspace),
4438 	    ("%s: non-current pmap %p", __func__, pmap));
4439 #if defined(SMP) && defined(INVARIANTS)
4440 	{
4441 		cpuset_t other_cpus;
4442 
4443 		sched_pin();
4444 		other_cpus = pmap->pm_active;
4445 		CPU_CLR(PCPU_GET(cpuid), &other_cpus);
4446 		sched_unpin();
4447 		KASSERT(CPU_EMPTY(&other_cpus),
4448 		    ("%s: pmap %p active on other cpus", __func__, pmap));
4449 	}
4450 #endif
4451 	SLIST_INIT(&free);
4452 	rw_wlock(&pvh_global_lock);
4453 	PMAP_LOCK(pmap);
4454 	sched_pin();
4455 	TAILQ_FOREACH_SAFE(pc, &pmap->pm_pvchunk, pc_list, npc) {
4456 		KASSERT(pc->pc_pmap == pmap, ("%s: wrong pmap %p %p",
4457 		    __func__, pmap, pc->pc_pmap));
4458 		allfree = TRUE;
4459 		for (field = 0; field < _NPCM; field++) {
4460 			inuse = (~(pc->pc_map[field])) & pc_freemask[field];
4461 			while (inuse != 0) {
4462 				bit = ffs(inuse) - 1;
4463 				bitmask = 1UL << bit;
4464 				idx = field * 32 + bit;
4465 				pv = &pc->pc_pventry[idx];
4466 				inuse &= ~bitmask;
4467 
4468 				/*
4469 				 * Note that we cannot remove wired pages
4470 				 * from a process' mapping at this time
4471 				 */
4472 				pte1p = pmap_pte1(pmap, pv->pv_va);
4473 				pte1 = pte1_load(pte1p);
4474 				if (pte1_is_section(pte1)) {
4475 					if (pte1_is_wired(pte1))  {
4476 						allfree = FALSE;
4477 						continue;
4478 					}
4479 					pte1_clear(pte1p);
4480 					pmap_remove_pte1_quick(pmap, pte1, pv,
4481 					    &free);
4482 				}
4483 				else if (pte1_is_link(pte1)) {
4484 					pte2p = pt2map_entry(pv->pv_va);
4485 					pte2 = pte2_load(pte2p);
4486 
4487 					if (!pte2_is_valid(pte2)) {
4488 						printf("%s: pmap %p va %#x "
4489 						    "pte2 %#x\n", __func__,
4490 						    pmap, pv->pv_va, pte2);
4491 						panic("bad pte2");
4492 					}
4493 
4494 					if (pte2_is_wired(pte2))   {
4495 						allfree = FALSE;
4496 						continue;
4497 					}
4498 					pte2_clear(pte2p);
4499 					pmap_remove_pte2_quick(pmap, pte2, pv,
4500 					    &free);
4501 				} else {
4502 					printf("%s: pmap %p va %#x pte1 %#x\n",
4503 					    __func__, pmap, pv->pv_va, pte1);
4504 					panic("bad pte1");
4505 				}
4506 
4507 				/* Mark free */
4508 				PV_STAT(pv_entry_frees++);
4509 				PV_STAT(pv_entry_spare++);
4510 				pv_entry_count--;
4511 				pc->pc_map[field] |= bitmask;
4512 			}
4513 		}
4514 		if (allfree) {
4515 			TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
4516 			free_pv_chunk(pc);
4517 		}
4518 	}
4519 	tlb_flush_all_ng_local();
4520 	sched_unpin();
4521 	rw_wunlock(&pvh_global_lock);
4522 	PMAP_UNLOCK(pmap);
4523 	vm_page_free_pages_toq(&free, false);
4524 }
4525 
4526 /*
4527  *  This code makes some *MAJOR* assumptions:
4528  *  1. Current pmap & pmap exists.
4529  *  2. Not wired.
4530  *  3. Read access.
4531  *  4. No L2 page table pages.
4532  *  but is *MUCH* faster than pmap_enter...
4533  */
4534 static vm_page_t
4535 pmap_enter_quick_locked(pmap_t pmap, vm_offset_t va, vm_page_t m,
4536     vm_prot_t prot, vm_page_t mpt2pg)
4537 {
4538 	pt2_entry_t *pte2p, pte2;
4539 	vm_paddr_t pa;
4540 	struct spglist free;
4541 	uint32_t l2prot;
4542 
4543 	KASSERT(va < kmi.clean_sva || va >= kmi.clean_eva ||
4544 	    (m->oflags & VPO_UNMANAGED) != 0,
4545 	    ("%s: managed mapping within the clean submap", __func__));
4546 	rw_assert(&pvh_global_lock, RA_WLOCKED);
4547 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4548 
4549 	/*
4550 	 * In the case that a L2 page table page is not
4551 	 * resident, we are creating it here.
4552 	 */
4553 	if (va < VM_MAXUSER_ADDRESS) {
4554 		u_int pte1_idx;
4555 		pt1_entry_t pte1, *pte1p;
4556 		vm_paddr_t pt2_pa;
4557 
4558 		/*
4559 		 * Get L1 page table things.
4560 		 */
4561 		pte1_idx = pte1_index(va);
4562 		pte1p = pmap_pte1(pmap, va);
4563 		pte1 = pte1_load(pte1p);
4564 
4565 		if (mpt2pg && (mpt2pg->pindex == (pte1_idx & ~PT2PG_MASK))) {
4566 			/*
4567 			 * Each of NPT2_IN_PG L2 page tables on the page can
4568 			 * come here. Make sure that associated L1 page table
4569 			 * link is established.
4570 			 *
4571 			 * QQQ: It comes that we don't establish all links to
4572 			 *      L2 page tables for newly allocated L2 page
4573 			 *      tables page.
4574 			 */
4575 			KASSERT(!pte1_is_section(pte1),
4576 			    ("%s: pte1 %#x is section", __func__, pte1));
4577 			if (!pte1_is_link(pte1)) {
4578 				pt2_pa = page_pt2pa(VM_PAGE_TO_PHYS(mpt2pg),
4579 				    pte1_idx);
4580 				pte1_store(pte1p, PTE1_LINK(pt2_pa));
4581 			}
4582 			pt2_wirecount_inc(mpt2pg, pte1_idx);
4583 		} else {
4584 			/*
4585 			 * If the L2 page table page is mapped, we just
4586 			 * increment the hold count, and activate it.
4587 			 */
4588 			if (pte1_is_section(pte1)) {
4589 				return (NULL);
4590 			} else if (pte1_is_link(pte1)) {
4591 				mpt2pg = PHYS_TO_VM_PAGE(pte1_link_pa(pte1));
4592 				pt2_wirecount_inc(mpt2pg, pte1_idx);
4593 			} else {
4594 				mpt2pg = _pmap_allocpte2(pmap, va,
4595 				    PMAP_ENTER_NOSLEEP);
4596 				if (mpt2pg == NULL)
4597 					return (NULL);
4598 			}
4599 		}
4600 	} else {
4601 		mpt2pg = NULL;
4602 	}
4603 
4604 	/*
4605 	 * This call to pt2map_entry() makes the assumption that we are
4606 	 * entering the page into the current pmap.  In order to support
4607 	 * quick entry into any pmap, one would likely use pmap_pte2_quick().
4608 	 * But that isn't as quick as pt2map_entry().
4609 	 */
4610 	pte2p = pt2map_entry(va);
4611 	pte2 = pte2_load(pte2p);
4612 	if (pte2_is_valid(pte2)) {
4613 		if (mpt2pg != NULL) {
4614 			/*
4615 			 * Remove extra pte2 reference
4616 			 */
4617 			pt2_wirecount_dec(mpt2pg, pte1_index(va));
4618 			mpt2pg = NULL;
4619 		}
4620 		return (NULL);
4621 	}
4622 
4623 	/*
4624 	 * Enter on the PV list if part of our managed memory.
4625 	 */
4626 	if ((m->oflags & VPO_UNMANAGED) == 0 &&
4627 	    !pmap_try_insert_pv_entry(pmap, va, m)) {
4628 		if (mpt2pg != NULL) {
4629 			SLIST_INIT(&free);
4630 			if (pmap_unwire_pt2(pmap, va, mpt2pg, &free)) {
4631 				pmap_tlb_flush(pmap, va);
4632 				vm_page_free_pages_toq(&free, false);
4633 			}
4634 
4635 			mpt2pg = NULL;
4636 		}
4637 		return (NULL);
4638 	}
4639 
4640 	/*
4641 	 * Increment counters
4642 	 */
4643 	pmap->pm_stats.resident_count++;
4644 
4645 	/*
4646 	 * Now validate mapping with RO protection
4647 	 */
4648 	pa = VM_PAGE_TO_PHYS(m);
4649 	l2prot = PTE2_RO | PTE2_NM;
4650 	if (va < VM_MAXUSER_ADDRESS)
4651 		l2prot |= PTE2_U | PTE2_NG;
4652 	if ((prot & VM_PROT_EXECUTE) == 0)
4653 		l2prot |= PTE2_NX;
4654 	else if (m->md.pat_mode == VM_MEMATTR_WB_WA && pmap != kernel_pmap) {
4655 		/*
4656 		 * Sync icache if exec permission and attribute VM_MEMATTR_WB_WA
4657 		 * is set. QQQ: For more info, see comments in pmap_enter().
4658 		 */
4659 		cache_icache_sync_fresh(va, pa, PAGE_SIZE);
4660 	}
4661 	pte2_store(pte2p, PTE2(pa, l2prot, vm_page_pte2_attr(m)));
4662 
4663 	return (mpt2pg);
4664 }
4665 
4666 void
4667 pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot)
4668 {
4669 
4670 	rw_wlock(&pvh_global_lock);
4671 	PMAP_LOCK(pmap);
4672 	(void)pmap_enter_quick_locked(pmap, va, m, prot, NULL);
4673 	rw_wunlock(&pvh_global_lock);
4674 	PMAP_UNLOCK(pmap);
4675 }
4676 
4677 /*
4678  *  Tries to create a read- and/or execute-only 1 MB page mapping.  Returns
4679  *  true if successful.  Returns false if (1) a mapping already exists at the
4680  *  specified virtual address or (2) a PV entry cannot be allocated without
4681  *  reclaiming another PV entry.
4682  */
4683 static bool
4684 pmap_enter_1mpage(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot)
4685 {
4686 	pt1_entry_t pte1;
4687 	vm_paddr_t pa;
4688 
4689 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4690 	pa = VM_PAGE_TO_PHYS(m);
4691 	pte1 = PTE1(pa, PTE1_NM | PTE1_RO, ATTR_TO_L1(vm_page_pte2_attr(m)));
4692 	if ((prot & VM_PROT_EXECUTE) == 0)
4693 		pte1 |= PTE1_NX;
4694 	if (va < VM_MAXUSER_ADDRESS)
4695 		pte1 |= PTE1_U;
4696 	if (pmap != kernel_pmap)
4697 		pte1 |= PTE1_NG;
4698 	return (pmap_enter_pte1(pmap, va, pte1, PMAP_ENTER_NOSLEEP |
4699 	    PMAP_ENTER_NOREPLACE | PMAP_ENTER_NORECLAIM, m) == KERN_SUCCESS);
4700 }
4701 
4702 /*
4703  *  Tries to create the specified 1 MB page mapping.  Returns KERN_SUCCESS if
4704  *  the mapping was created, and either KERN_FAILURE or KERN_RESOURCE_SHORTAGE
4705  *  otherwise.  Returns KERN_FAILURE if PMAP_ENTER_NOREPLACE was specified and
4706  *  a mapping already exists at the specified virtual address.  Returns
4707  *  KERN_RESOURCE_SHORTAGE if PMAP_ENTER_NORECLAIM was specified and PV entry
4708  *  allocation failed.
4709  */
4710 static int
4711 pmap_enter_pte1(pmap_t pmap, vm_offset_t va, pt1_entry_t pte1, u_int flags,
4712     vm_page_t m)
4713 {
4714 	struct spglist free;
4715 	pt1_entry_t opte1, *pte1p;
4716 	pt2_entry_t pte2, *pte2p;
4717 	vm_offset_t cur, end;
4718 	vm_page_t mt;
4719 
4720 	rw_assert(&pvh_global_lock, RA_WLOCKED);
4721 	KASSERT((pte1 & (PTE1_NM | PTE1_RO)) == 0 ||
4722 	    (pte1 & (PTE1_NM | PTE1_RO)) == (PTE1_NM | PTE1_RO),
4723 	    ("%s: pte1 has inconsistent NM and RO attributes", __func__));
4724 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4725 	pte1p = pmap_pte1(pmap, va);
4726 	opte1 = pte1_load(pte1p);
4727 	if (pte1_is_valid(opte1)) {
4728 		if ((flags & PMAP_ENTER_NOREPLACE) != 0) {
4729 			CTR3(KTR_PMAP, "%s: failure for va %#lx in pmap %p",
4730 			    __func__, va, pmap);
4731 			return (KERN_FAILURE);
4732 		}
4733 		/* Break the existing mapping(s). */
4734 		SLIST_INIT(&free);
4735 		if (pte1_is_section(opte1)) {
4736 			/*
4737 			 * If the section resulted from a promotion, then a
4738 			 * reserved PT page could be freed.
4739 			 */
4740 			pmap_remove_pte1(pmap, pte1p, va, &free);
4741 		} else {
4742 			sched_pin();
4743 			end = va + PTE1_SIZE;
4744 			for (cur = va, pte2p = pmap_pte2_quick(pmap, va);
4745 			    cur != end; cur += PAGE_SIZE, pte2p++) {
4746 				pte2 = pte2_load(pte2p);
4747 				if (!pte2_is_valid(pte2))
4748 					continue;
4749 				if (pmap_remove_pte2(pmap, pte2p, cur, &free))
4750 					break;
4751 			}
4752 			sched_unpin();
4753 		}
4754 		vm_page_free_pages_toq(&free, false);
4755 	}
4756 	if ((m->oflags & VPO_UNMANAGED) == 0) {
4757 		/*
4758 		 * Abort this mapping if its PV entry could not be created.
4759 		 */
4760 		if (!pmap_pv_insert_pte1(pmap, va, pte1, flags)) {
4761 			CTR3(KTR_PMAP, "%s: failure for va %#lx in pmap %p",
4762 			    __func__, va, pmap);
4763 			return (KERN_RESOURCE_SHORTAGE);
4764 		}
4765 		if ((pte1 & PTE1_RO) == 0) {
4766 			for (mt = m; mt < &m[PTE1_SIZE / PAGE_SIZE]; mt++)
4767 				vm_page_aflag_set(mt, PGA_WRITEABLE);
4768 		}
4769 	}
4770 
4771 	/*
4772 	 * Increment counters.
4773 	 */
4774 	if (pte1_is_wired(pte1))
4775 		pmap->pm_stats.wired_count += PTE1_SIZE / PAGE_SIZE;
4776 	pmap->pm_stats.resident_count += PTE1_SIZE / PAGE_SIZE;
4777 
4778 	/*
4779 	 * Sync icache if exec permission and attribute VM_MEMATTR_WB_WA
4780 	 * is set.  QQQ: For more info, see comments in pmap_enter().
4781 	 */
4782 	if ((pte1 & PTE1_NX) == 0 && m->md.pat_mode == VM_MEMATTR_WB_WA &&
4783 	    pmap != kernel_pmap && (!pte1_is_section(opte1) ||
4784 	    pte1_pa(opte1) != VM_PAGE_TO_PHYS(m) || (opte1 & PTE2_NX) != 0))
4785 		cache_icache_sync_fresh(va, VM_PAGE_TO_PHYS(m), PTE1_SIZE);
4786 
4787 	/*
4788 	 * Map the section.
4789 	 */
4790 	pte1_store(pte1p, pte1);
4791 
4792 	pmap_pte1_mappings++;
4793 	CTR3(KTR_PMAP, "%s: success for va %#lx in pmap %p", __func__, va,
4794 	    pmap);
4795 	return (KERN_SUCCESS);
4796 }
4797 
4798 /*
4799  *  Maps a sequence of resident pages belonging to the same object.
4800  *  The sequence begins with the given page m_start.  This page is
4801  *  mapped at the given virtual address start.  Each subsequent page is
4802  *  mapped at a virtual address that is offset from start by the same
4803  *  amount as the page is offset from m_start within the object.  The
4804  *  last page in the sequence is the page with the largest offset from
4805  *  m_start that can be mapped at a virtual address less than the given
4806  *  virtual address end.  Not every virtual page between start and end
4807  *  is mapped; only those for which a resident page exists with the
4808  *  corresponding offset from m_start are mapped.
4809  */
4810 void
4811 pmap_enter_object(pmap_t pmap, vm_offset_t start, vm_offset_t end,
4812     vm_page_t m_start, vm_prot_t prot)
4813 {
4814 	vm_offset_t va;
4815 	vm_page_t m, mpt2pg;
4816 	vm_pindex_t diff, psize;
4817 
4818 	PDEBUG(6, printf("%s: pmap %p start %#x end  %#x m %p prot %#x\n",
4819 	    __func__, pmap, start, end, m_start, prot));
4820 
4821 	VM_OBJECT_ASSERT_LOCKED(m_start->object);
4822 	psize = atop(end - start);
4823 	mpt2pg = NULL;
4824 	m = m_start;
4825 	rw_wlock(&pvh_global_lock);
4826 	PMAP_LOCK(pmap);
4827 	while (m != NULL && (diff = m->pindex - m_start->pindex) < psize) {
4828 		va = start + ptoa(diff);
4829 		if ((va & PTE1_OFFSET) == 0 && va + PTE1_SIZE <= end &&
4830 		    m->psind == 1 && sp_enabled &&
4831 		    pmap_enter_1mpage(pmap, va, m, prot))
4832 			m = &m[PTE1_SIZE / PAGE_SIZE - 1];
4833 		else
4834 			mpt2pg = pmap_enter_quick_locked(pmap, va, m, prot,
4835 			    mpt2pg);
4836 		m = TAILQ_NEXT(m, listq);
4837 	}
4838 	rw_wunlock(&pvh_global_lock);
4839 	PMAP_UNLOCK(pmap);
4840 }
4841 
4842 /*
4843  *  This code maps large physical mmap regions into the
4844  *  processor address space.  Note that some shortcuts
4845  *  are taken, but the code works.
4846  */
4847 void
4848 pmap_object_init_pt(pmap_t pmap, vm_offset_t addr, vm_object_t object,
4849     vm_pindex_t pindex, vm_size_t size)
4850 {
4851 	pt1_entry_t *pte1p;
4852 	vm_paddr_t pa, pte2_pa;
4853 	vm_page_t p;
4854 	vm_memattr_t pat_mode;
4855 	u_int l1attr, l1prot;
4856 
4857 	VM_OBJECT_ASSERT_WLOCKED(object);
4858 	KASSERT(object->type == OBJT_DEVICE || object->type == OBJT_SG,
4859 	    ("%s: non-device object", __func__));
4860 	if ((addr & PTE1_OFFSET) == 0 && (size & PTE1_OFFSET) == 0) {
4861 		if (!vm_object_populate(object, pindex, pindex + atop(size)))
4862 			return;
4863 		p = vm_page_lookup(object, pindex);
4864 		KASSERT(p->valid == VM_PAGE_BITS_ALL,
4865 		    ("%s: invalid page %p", __func__, p));
4866 		pat_mode = p->md.pat_mode;
4867 
4868 		/*
4869 		 * Abort the mapping if the first page is not physically
4870 		 * aligned to a 1MB page boundary.
4871 		 */
4872 		pte2_pa = VM_PAGE_TO_PHYS(p);
4873 		if (pte2_pa & PTE1_OFFSET)
4874 			return;
4875 
4876 		/*
4877 		 * Skip the first page. Abort the mapping if the rest of
4878 		 * the pages are not physically contiguous or have differing
4879 		 * memory attributes.
4880 		 */
4881 		p = TAILQ_NEXT(p, listq);
4882 		for (pa = pte2_pa + PAGE_SIZE; pa < pte2_pa + size;
4883 		    pa += PAGE_SIZE) {
4884 			KASSERT(p->valid == VM_PAGE_BITS_ALL,
4885 			    ("%s: invalid page %p", __func__, p));
4886 			if (pa != VM_PAGE_TO_PHYS(p) ||
4887 			    pat_mode != p->md.pat_mode)
4888 				return;
4889 			p = TAILQ_NEXT(p, listq);
4890 		}
4891 
4892 		/*
4893 		 * Map using 1MB pages.
4894 		 *
4895 		 * QQQ: Well, we are mapping a section, so same condition must
4896 		 * be hold like during promotion. It looks that only RW mapping
4897 		 * is done here, so readonly mapping must be done elsewhere.
4898 		 */
4899 		l1prot = PTE1_U | PTE1_NG | PTE1_RW | PTE1_M | PTE1_A;
4900 		l1attr = ATTR_TO_L1(vm_memattr_to_pte2(pat_mode));
4901 		PMAP_LOCK(pmap);
4902 		for (pa = pte2_pa; pa < pte2_pa + size; pa += PTE1_SIZE) {
4903 			pte1p = pmap_pte1(pmap, addr);
4904 			if (!pte1_is_valid(pte1_load(pte1p))) {
4905 				pte1_store(pte1p, PTE1(pa, l1prot, l1attr));
4906 				pmap->pm_stats.resident_count += PTE1_SIZE /
4907 				    PAGE_SIZE;
4908 				pmap_pte1_mappings++;
4909 			}
4910 			/* Else continue on if the PTE1 is already valid. */
4911 			addr += PTE1_SIZE;
4912 		}
4913 		PMAP_UNLOCK(pmap);
4914 	}
4915 }
4916 
4917 /*
4918  *  Do the things to protect a 1mpage in a process.
4919  */
4920 static void
4921 pmap_protect_pte1(pmap_t pmap, pt1_entry_t *pte1p, vm_offset_t sva,
4922     vm_prot_t prot)
4923 {
4924 	pt1_entry_t npte1, opte1;
4925 	vm_offset_t eva, va;
4926 	vm_page_t m;
4927 
4928 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4929 	KASSERT((sva & PTE1_OFFSET) == 0,
4930 	    ("%s: sva is not 1mpage aligned", __func__));
4931 
4932 	opte1 = npte1 = pte1_load(pte1p);
4933 	if (pte1_is_managed(opte1) && pte1_is_dirty(opte1)) {
4934 		eva = sva + PTE1_SIZE;
4935 		for (va = sva, m = PHYS_TO_VM_PAGE(pte1_pa(opte1));
4936 		    va < eva; va += PAGE_SIZE, m++)
4937 			vm_page_dirty(m);
4938 	}
4939 	if ((prot & VM_PROT_WRITE) == 0)
4940 		npte1 |= PTE1_RO | PTE1_NM;
4941 	if ((prot & VM_PROT_EXECUTE) == 0)
4942 		npte1 |= PTE1_NX;
4943 
4944 	/*
4945 	 * QQQ: Herein, execute permission is never set.
4946 	 *      It only can be cleared. So, no icache
4947 	 *      syncing is needed.
4948 	 */
4949 
4950 	if (npte1 != opte1) {
4951 		pte1_store(pte1p, npte1);
4952 		pmap_tlb_flush(pmap, sva);
4953 	}
4954 }
4955 
4956 /*
4957  *	Set the physical protection on the
4958  *	specified range of this map as requested.
4959  */
4960 void
4961 pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot)
4962 {
4963 	boolean_t pv_lists_locked;
4964 	vm_offset_t nextva;
4965 	pt1_entry_t *pte1p, pte1;
4966 	pt2_entry_t *pte2p, opte2, npte2;
4967 
4968 	KASSERT((prot & ~VM_PROT_ALL) == 0, ("invalid prot %x", prot));
4969 	if (prot == VM_PROT_NONE) {
4970 		pmap_remove(pmap, sva, eva);
4971 		return;
4972 	}
4973 
4974 	if ((prot & (VM_PROT_WRITE | VM_PROT_EXECUTE)) ==
4975 	    (VM_PROT_WRITE | VM_PROT_EXECUTE))
4976 		return;
4977 
4978 	if (pmap_is_current(pmap))
4979 		pv_lists_locked = FALSE;
4980 	else {
4981 		pv_lists_locked = TRUE;
4982 resume:
4983 		rw_wlock(&pvh_global_lock);
4984 		sched_pin();
4985 	}
4986 
4987 	PMAP_LOCK(pmap);
4988 	for (; sva < eva; sva = nextva) {
4989 		/*
4990 		 * Calculate address for next L2 page table.
4991 		 */
4992 		nextva = pte1_trunc(sva + PTE1_SIZE);
4993 		if (nextva < sva)
4994 			nextva = eva;
4995 
4996 		pte1p = pmap_pte1(pmap, sva);
4997 		pte1 = pte1_load(pte1p);
4998 
4999 		/*
5000 		 * Weed out invalid mappings. Note: we assume that L1 page
5001 		 * page table is always allocated, and in kernel virtual.
5002 		 */
5003 		if (pte1 == 0)
5004 			continue;
5005 
5006 		if (pte1_is_section(pte1)) {
5007 			/*
5008 			 * Are we protecting the entire large page?  If not,
5009 			 * demote the mapping and fall through.
5010 			 */
5011 			if (sva + PTE1_SIZE == nextva && eva >= nextva) {
5012 				pmap_protect_pte1(pmap, pte1p, sva, prot);
5013 				continue;
5014 			} else {
5015 				if (!pv_lists_locked) {
5016 					pv_lists_locked = TRUE;
5017 					if (!rw_try_wlock(&pvh_global_lock)) {
5018 						PMAP_UNLOCK(pmap);
5019 						goto resume;
5020 					}
5021 					sched_pin();
5022 				}
5023 				if (!pmap_demote_pte1(pmap, pte1p, sva)) {
5024 					/*
5025 					 * The large page mapping
5026 					 * was destroyed.
5027 					 */
5028 					continue;
5029 				}
5030 #ifdef INVARIANTS
5031 				else {
5032 					/* Update pte1 after demotion */
5033 					pte1 = pte1_load(pte1p);
5034 				}
5035 #endif
5036 			}
5037 		}
5038 
5039 		KASSERT(pte1_is_link(pte1), ("%s: pmap %p va %#x pte1 %#x at %p"
5040 		    " is not link", __func__, pmap, sva, pte1, pte1p));
5041 
5042 		/*
5043 		 * Limit our scan to either the end of the va represented
5044 		 * by the current L2 page table page, or to the end of the
5045 		 * range being protected.
5046 		 */
5047 		if (nextva > eva)
5048 			nextva = eva;
5049 
5050 		for (pte2p = pmap_pte2_quick(pmap, sva); sva != nextva; pte2p++,
5051 		    sva += PAGE_SIZE) {
5052 			vm_page_t m;
5053 
5054 			opte2 = npte2 = pte2_load(pte2p);
5055 			if (!pte2_is_valid(opte2))
5056 				continue;
5057 
5058 			if ((prot & VM_PROT_WRITE) == 0) {
5059 				if (pte2_is_managed(opte2) &&
5060 				    pte2_is_dirty(opte2)) {
5061 					m = PHYS_TO_VM_PAGE(pte2_pa(opte2));
5062 					vm_page_dirty(m);
5063 				}
5064 				npte2 |= PTE2_RO | PTE2_NM;
5065 			}
5066 
5067 			if ((prot & VM_PROT_EXECUTE) == 0)
5068 				npte2 |= PTE2_NX;
5069 
5070 			/*
5071 			 * QQQ: Herein, execute permission is never set.
5072 			 *      It only can be cleared. So, no icache
5073 			 *      syncing is needed.
5074 			 */
5075 
5076 			if (npte2 != opte2) {
5077 				pte2_store(pte2p, npte2);
5078 				pmap_tlb_flush(pmap, sva);
5079 			}
5080 		}
5081 	}
5082 	if (pv_lists_locked) {
5083 		sched_unpin();
5084 		rw_wunlock(&pvh_global_lock);
5085 	}
5086 	PMAP_UNLOCK(pmap);
5087 }
5088 
5089 /*
5090  *	pmap_pvh_wired_mappings:
5091  *
5092  *	Return the updated number "count" of managed mappings that are wired.
5093  */
5094 static int
5095 pmap_pvh_wired_mappings(struct md_page *pvh, int count)
5096 {
5097 	pmap_t pmap;
5098 	pt1_entry_t pte1;
5099 	pt2_entry_t pte2;
5100 	pv_entry_t pv;
5101 
5102 	rw_assert(&pvh_global_lock, RA_WLOCKED);
5103 	sched_pin();
5104 	TAILQ_FOREACH(pv, &pvh->pv_list, pv_next) {
5105 		pmap = PV_PMAP(pv);
5106 		PMAP_LOCK(pmap);
5107 		pte1 = pte1_load(pmap_pte1(pmap, pv->pv_va));
5108 		if (pte1_is_section(pte1)) {
5109 			if (pte1_is_wired(pte1))
5110 				count++;
5111 		} else {
5112 			KASSERT(pte1_is_link(pte1),
5113 			    ("%s: pte1 %#x is not link", __func__, pte1));
5114 			pte2 = pte2_load(pmap_pte2_quick(pmap, pv->pv_va));
5115 			if (pte2_is_wired(pte2))
5116 				count++;
5117 		}
5118 		PMAP_UNLOCK(pmap);
5119 	}
5120 	sched_unpin();
5121 	return (count);
5122 }
5123 
5124 /*
5125  *	pmap_page_wired_mappings:
5126  *
5127  *	Return the number of managed mappings to the given physical page
5128  *	that are wired.
5129  */
5130 int
5131 pmap_page_wired_mappings(vm_page_t m)
5132 {
5133 	int count;
5134 
5135 	count = 0;
5136 	if ((m->oflags & VPO_UNMANAGED) != 0)
5137 		return (count);
5138 	rw_wlock(&pvh_global_lock);
5139 	count = pmap_pvh_wired_mappings(&m->md, count);
5140 	if ((m->flags & PG_FICTITIOUS) == 0) {
5141 		count = pmap_pvh_wired_mappings(pa_to_pvh(VM_PAGE_TO_PHYS(m)),
5142 		    count);
5143 	}
5144 	rw_wunlock(&pvh_global_lock);
5145 	return (count);
5146 }
5147 
5148 /*
5149  *  Returns TRUE if any of the given mappings were used to modify
5150  *  physical memory.  Otherwise, returns FALSE.  Both page and 1mpage
5151  *  mappings are supported.
5152  */
5153 static boolean_t
5154 pmap_is_modified_pvh(struct md_page *pvh)
5155 {
5156 	pv_entry_t pv;
5157 	pt1_entry_t pte1;
5158 	pt2_entry_t pte2;
5159 	pmap_t pmap;
5160 	boolean_t rv;
5161 
5162 	rw_assert(&pvh_global_lock, RA_WLOCKED);
5163 	rv = FALSE;
5164 	sched_pin();
5165 	TAILQ_FOREACH(pv, &pvh->pv_list, pv_next) {
5166 		pmap = PV_PMAP(pv);
5167 		PMAP_LOCK(pmap);
5168 		pte1 = pte1_load(pmap_pte1(pmap, pv->pv_va));
5169 		if (pte1_is_section(pte1)) {
5170 			rv = pte1_is_dirty(pte1);
5171 		} else {
5172 			KASSERT(pte1_is_link(pte1),
5173 			    ("%s: pte1 %#x is not link", __func__, pte1));
5174 			pte2 = pte2_load(pmap_pte2_quick(pmap, pv->pv_va));
5175 			rv = pte2_is_dirty(pte2);
5176 		}
5177 		PMAP_UNLOCK(pmap);
5178 		if (rv)
5179 			break;
5180 	}
5181 	sched_unpin();
5182 	return (rv);
5183 }
5184 
5185 /*
5186  *	pmap_is_modified:
5187  *
5188  *	Return whether or not the specified physical page was modified
5189  *	in any physical maps.
5190  */
5191 boolean_t
5192 pmap_is_modified(vm_page_t m)
5193 {
5194 	boolean_t rv;
5195 
5196 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
5197 	    ("%s: page %p is not managed", __func__, m));
5198 
5199 	/*
5200 	 * If the page is not exclusive busied, then PGA_WRITEABLE cannot be
5201 	 * concurrently set while the object is locked.  Thus, if PGA_WRITEABLE
5202 	 * is clear, no PTE2s can have PG_M set.
5203 	 */
5204 	VM_OBJECT_ASSERT_WLOCKED(m->object);
5205 	if (!vm_page_xbusied(m) && (m->aflags & PGA_WRITEABLE) == 0)
5206 		return (FALSE);
5207 	rw_wlock(&pvh_global_lock);
5208 	rv = pmap_is_modified_pvh(&m->md) ||
5209 	    ((m->flags & PG_FICTITIOUS) == 0 &&
5210 	    pmap_is_modified_pvh(pa_to_pvh(VM_PAGE_TO_PHYS(m))));
5211 	rw_wunlock(&pvh_global_lock);
5212 	return (rv);
5213 }
5214 
5215 /*
5216  *	pmap_is_prefaultable:
5217  *
5218  *	Return whether or not the specified virtual address is eligible
5219  *	for prefault.
5220  */
5221 boolean_t
5222 pmap_is_prefaultable(pmap_t pmap, vm_offset_t addr)
5223 {
5224 	pt1_entry_t pte1;
5225 	pt2_entry_t pte2;
5226 	boolean_t rv;
5227 
5228 	rv = FALSE;
5229 	PMAP_LOCK(pmap);
5230 	pte1 = pte1_load(pmap_pte1(pmap, addr));
5231 	if (pte1_is_link(pte1)) {
5232 		pte2 = pte2_load(pt2map_entry(addr));
5233 		rv = !pte2_is_valid(pte2) ;
5234 	}
5235 	PMAP_UNLOCK(pmap);
5236 	return (rv);
5237 }
5238 
5239 /*
5240  *  Returns TRUE if any of the given mappings were referenced and FALSE
5241  *  otherwise. Both page and 1mpage mappings are supported.
5242  */
5243 static boolean_t
5244 pmap_is_referenced_pvh(struct md_page *pvh)
5245 {
5246 
5247 	pv_entry_t pv;
5248 	pt1_entry_t pte1;
5249 	pt2_entry_t pte2;
5250 	pmap_t pmap;
5251 	boolean_t rv;
5252 
5253 	rw_assert(&pvh_global_lock, RA_WLOCKED);
5254 	rv = FALSE;
5255 	sched_pin();
5256 	TAILQ_FOREACH(pv, &pvh->pv_list, pv_next) {
5257 		pmap = PV_PMAP(pv);
5258 		PMAP_LOCK(pmap);
5259 		pte1 = pte1_load(pmap_pte1(pmap, pv->pv_va));
5260 		if (pte1_is_section(pte1)) {
5261 			rv = (pte1 & (PTE1_A | PTE1_V)) == (PTE1_A | PTE1_V);
5262 		} else {
5263 			pte2 = pte2_load(pmap_pte2_quick(pmap, pv->pv_va));
5264 			rv = (pte2 & (PTE2_A | PTE2_V)) == (PTE2_A | PTE2_V);
5265 		}
5266 		PMAP_UNLOCK(pmap);
5267 		if (rv)
5268 			break;
5269 	}
5270 	sched_unpin();
5271 	return (rv);
5272 }
5273 
5274 /*
5275  *	pmap_is_referenced:
5276  *
5277  *	Return whether or not the specified physical page was referenced
5278  *	in any physical maps.
5279  */
5280 boolean_t
5281 pmap_is_referenced(vm_page_t m)
5282 {
5283 	boolean_t rv;
5284 
5285 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
5286 	    ("%s: page %p is not managed", __func__, m));
5287 	rw_wlock(&pvh_global_lock);
5288 	rv = pmap_is_referenced_pvh(&m->md) ||
5289 	    ((m->flags & PG_FICTITIOUS) == 0 &&
5290 	    pmap_is_referenced_pvh(pa_to_pvh(VM_PAGE_TO_PHYS(m))));
5291 	rw_wunlock(&pvh_global_lock);
5292 	return (rv);
5293 }
5294 
5295 /*
5296  *	pmap_ts_referenced:
5297  *
5298  *	Return a count of reference bits for a page, clearing those bits.
5299  *	It is not necessary for every reference bit to be cleared, but it
5300  *	is necessary that 0 only be returned when there are truly no
5301  *	reference bits set.
5302  *
5303  *	As an optimization, update the page's dirty field if a modified bit is
5304  *	found while counting reference bits.  This opportunistic update can be
5305  *	performed at low cost and can eliminate the need for some future calls
5306  *	to pmap_is_modified().  However, since this function stops after
5307  *	finding PMAP_TS_REFERENCED_MAX reference bits, it may not detect some
5308  *	dirty pages.  Those dirty pages will only be detected by a future call
5309  *	to pmap_is_modified().
5310  */
5311 int
5312 pmap_ts_referenced(vm_page_t m)
5313 {
5314 	struct md_page *pvh;
5315 	pv_entry_t pv, pvf;
5316 	pmap_t pmap;
5317 	pt1_entry_t  *pte1p, opte1;
5318 	pt2_entry_t *pte2p, opte2;
5319 	vm_paddr_t pa;
5320 	int rtval = 0;
5321 
5322 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
5323 	    ("%s: page %p is not managed", __func__, m));
5324 	pa = VM_PAGE_TO_PHYS(m);
5325 	pvh = pa_to_pvh(pa);
5326 	rw_wlock(&pvh_global_lock);
5327 	sched_pin();
5328 	if ((m->flags & PG_FICTITIOUS) != 0 ||
5329 	    (pvf = TAILQ_FIRST(&pvh->pv_list)) == NULL)
5330 		goto small_mappings;
5331 	pv = pvf;
5332 	do {
5333 		pmap = PV_PMAP(pv);
5334 		PMAP_LOCK(pmap);
5335 		pte1p = pmap_pte1(pmap, pv->pv_va);
5336 		opte1 = pte1_load(pte1p);
5337 		if (pte1_is_dirty(opte1)) {
5338 			/*
5339 			 * Although "opte1" is mapping a 1MB page, because
5340 			 * this function is called at a 4KB page granularity,
5341 			 * we only update the 4KB page under test.
5342 			 */
5343 			vm_page_dirty(m);
5344 		}
5345 		if ((opte1 & PTE1_A) != 0) {
5346 			/*
5347 			 * Since this reference bit is shared by 256 4KB pages,
5348 			 * it should not be cleared every time it is tested.
5349 			 * Apply a simple "hash" function on the physical page
5350 			 * number, the virtual section number, and the pmap
5351 			 * address to select one 4KB page out of the 256
5352 			 * on which testing the reference bit will result
5353 			 * in clearing that bit. This function is designed
5354 			 * to avoid the selection of the same 4KB page
5355 			 * for every 1MB page mapping.
5356 			 *
5357 			 * On demotion, a mapping that hasn't been referenced
5358 			 * is simply destroyed.  To avoid the possibility of a
5359 			 * subsequent page fault on a demoted wired mapping,
5360 			 * always leave its reference bit set.  Moreover,
5361 			 * since the section is wired, the current state of
5362 			 * its reference bit won't affect page replacement.
5363 			 */
5364 			 if ((((pa >> PAGE_SHIFT) ^ (pv->pv_va >> PTE1_SHIFT) ^
5365 			    (uintptr_t)pmap) & (NPTE2_IN_PG - 1)) == 0 &&
5366 			    !pte1_is_wired(opte1)) {
5367 				pte1_clear_bit(pte1p, PTE1_A);
5368 				pmap_tlb_flush(pmap, pv->pv_va);
5369 			}
5370 			rtval++;
5371 		}
5372 		PMAP_UNLOCK(pmap);
5373 		/* Rotate the PV list if it has more than one entry. */
5374 		if (TAILQ_NEXT(pv, pv_next) != NULL) {
5375 			TAILQ_REMOVE(&pvh->pv_list, pv, pv_next);
5376 			TAILQ_INSERT_TAIL(&pvh->pv_list, pv, pv_next);
5377 		}
5378 		if (rtval >= PMAP_TS_REFERENCED_MAX)
5379 			goto out;
5380 	} while ((pv = TAILQ_FIRST(&pvh->pv_list)) != pvf);
5381 small_mappings:
5382 	if ((pvf = TAILQ_FIRST(&m->md.pv_list)) == NULL)
5383 		goto out;
5384 	pv = pvf;
5385 	do {
5386 		pmap = PV_PMAP(pv);
5387 		PMAP_LOCK(pmap);
5388 		pte1p = pmap_pte1(pmap, pv->pv_va);
5389 		KASSERT(pte1_is_link(pte1_load(pte1p)),
5390 		    ("%s: not found a link in page %p's pv list", __func__, m));
5391 
5392 		pte2p = pmap_pte2_quick(pmap, pv->pv_va);
5393 		opte2 = pte2_load(pte2p);
5394 		if (pte2_is_dirty(opte2))
5395 			vm_page_dirty(m);
5396 		if ((opte2 & PTE2_A) != 0) {
5397 			pte2_clear_bit(pte2p, PTE2_A);
5398 			pmap_tlb_flush(pmap, pv->pv_va);
5399 			rtval++;
5400 		}
5401 		PMAP_UNLOCK(pmap);
5402 		/* Rotate the PV list if it has more than one entry. */
5403 		if (TAILQ_NEXT(pv, pv_next) != NULL) {
5404 			TAILQ_REMOVE(&m->md.pv_list, pv, pv_next);
5405 			TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_next);
5406 		}
5407 	} while ((pv = TAILQ_FIRST(&m->md.pv_list)) != pvf && rtval <
5408 	    PMAP_TS_REFERENCED_MAX);
5409 out:
5410 	sched_unpin();
5411 	rw_wunlock(&pvh_global_lock);
5412 	return (rtval);
5413 }
5414 
5415 /*
5416  *	Clear the wired attribute from the mappings for the specified range of
5417  *	addresses in the given pmap.  Every valid mapping within that range
5418  *	must have the wired attribute set.  In contrast, invalid mappings
5419  *	cannot have the wired attribute set, so they are ignored.
5420  *
5421  *	The wired attribute of the page table entry is not a hardware feature,
5422  *	so there is no need to invalidate any TLB entries.
5423  */
5424 void
5425 pmap_unwire(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
5426 {
5427 	vm_offset_t nextva;
5428 	pt1_entry_t *pte1p, pte1;
5429 	pt2_entry_t *pte2p, pte2;
5430 	boolean_t pv_lists_locked;
5431 
5432 	if (pmap_is_current(pmap))
5433 		pv_lists_locked = FALSE;
5434 	else {
5435 		pv_lists_locked = TRUE;
5436 resume:
5437 		rw_wlock(&pvh_global_lock);
5438 		sched_pin();
5439 	}
5440 	PMAP_LOCK(pmap);
5441 	for (; sva < eva; sva = nextva) {
5442 		nextva = pte1_trunc(sva + PTE1_SIZE);
5443 		if (nextva < sva)
5444 			nextva = eva;
5445 
5446 		pte1p = pmap_pte1(pmap, sva);
5447 		pte1 = pte1_load(pte1p);
5448 
5449 		/*
5450 		 * Weed out invalid mappings. Note: we assume that L1 page
5451 		 * page table is always allocated, and in kernel virtual.
5452 		 */
5453 		if (pte1 == 0)
5454 			continue;
5455 
5456 		if (pte1_is_section(pte1)) {
5457 			if (!pte1_is_wired(pte1))
5458 				panic("%s: pte1 %#x not wired", __func__, pte1);
5459 
5460 			/*
5461 			 * Are we unwiring the entire large page?  If not,
5462 			 * demote the mapping and fall through.
5463 			 */
5464 			if (sva + PTE1_SIZE == nextva && eva >= nextva) {
5465 				pte1_clear_bit(pte1p, PTE1_W);
5466 				pmap->pm_stats.wired_count -= PTE1_SIZE /
5467 				    PAGE_SIZE;
5468 				continue;
5469 			} else {
5470 				if (!pv_lists_locked) {
5471 					pv_lists_locked = TRUE;
5472 					if (!rw_try_wlock(&pvh_global_lock)) {
5473 						PMAP_UNLOCK(pmap);
5474 						/* Repeat sva. */
5475 						goto resume;
5476 					}
5477 					sched_pin();
5478 				}
5479 				if (!pmap_demote_pte1(pmap, pte1p, sva))
5480 					panic("%s: demotion failed", __func__);
5481 #ifdef INVARIANTS
5482 				else {
5483 					/* Update pte1 after demotion */
5484 					pte1 = pte1_load(pte1p);
5485 				}
5486 #endif
5487 			}
5488 		}
5489 
5490 		KASSERT(pte1_is_link(pte1), ("%s: pmap %p va %#x pte1 %#x at %p"
5491 		    " is not link", __func__, pmap, sva, pte1, pte1p));
5492 
5493 		/*
5494 		 * Limit our scan to either the end of the va represented
5495 		 * by the current L2 page table page, or to the end of the
5496 		 * range being protected.
5497 		 */
5498 		if (nextva > eva)
5499 			nextva = eva;
5500 
5501 		for (pte2p = pmap_pte2_quick(pmap, sva); sva != nextva; pte2p++,
5502 		    sva += PAGE_SIZE) {
5503 			pte2 = pte2_load(pte2p);
5504 			if (!pte2_is_valid(pte2))
5505 				continue;
5506 			if (!pte2_is_wired(pte2))
5507 				panic("%s: pte2 %#x is missing PTE2_W",
5508 				    __func__, pte2);
5509 
5510 			/*
5511 			 * PTE2_W must be cleared atomically. Although the pmap
5512 			 * lock synchronizes access to PTE2_W, another processor
5513 			 * could be changing PTE2_NM and/or PTE2_A concurrently.
5514 			 */
5515 			pte2_clear_bit(pte2p, PTE2_W);
5516 			pmap->pm_stats.wired_count--;
5517 		}
5518 	}
5519 	if (pv_lists_locked) {
5520 		sched_unpin();
5521 		rw_wunlock(&pvh_global_lock);
5522 	}
5523 	PMAP_UNLOCK(pmap);
5524 }
5525 
5526 /*
5527  *  Clear the write and modified bits in each of the given page's mappings.
5528  */
5529 void
5530 pmap_remove_write(vm_page_t m)
5531 {
5532 	struct md_page *pvh;
5533 	pv_entry_t next_pv, pv;
5534 	pmap_t pmap;
5535 	pt1_entry_t *pte1p;
5536 	pt2_entry_t *pte2p, opte2;
5537 	vm_offset_t va;
5538 
5539 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
5540 	    ("%s: page %p is not managed", __func__, m));
5541 
5542 	/*
5543 	 * If the page is not exclusive busied, then PGA_WRITEABLE cannot be
5544 	 * set by another thread while the object is locked.  Thus,
5545 	 * if PGA_WRITEABLE is clear, no page table entries need updating.
5546 	 */
5547 	VM_OBJECT_ASSERT_WLOCKED(m->object);
5548 	if (!vm_page_xbusied(m) && (m->aflags & PGA_WRITEABLE) == 0)
5549 		return;
5550 	rw_wlock(&pvh_global_lock);
5551 	sched_pin();
5552 	if ((m->flags & PG_FICTITIOUS) != 0)
5553 		goto small_mappings;
5554 	pvh = pa_to_pvh(VM_PAGE_TO_PHYS(m));
5555 	TAILQ_FOREACH_SAFE(pv, &pvh->pv_list, pv_next, next_pv) {
5556 		va = pv->pv_va;
5557 		pmap = PV_PMAP(pv);
5558 		PMAP_LOCK(pmap);
5559 		pte1p = pmap_pte1(pmap, va);
5560 		if (!(pte1_load(pte1p) & PTE1_RO))
5561 			(void)pmap_demote_pte1(pmap, pte1p, va);
5562 		PMAP_UNLOCK(pmap);
5563 	}
5564 small_mappings:
5565 	TAILQ_FOREACH(pv, &m->md.pv_list, pv_next) {
5566 		pmap = PV_PMAP(pv);
5567 		PMAP_LOCK(pmap);
5568 		pte1p = pmap_pte1(pmap, pv->pv_va);
5569 		KASSERT(!pte1_is_section(pte1_load(pte1p)), ("%s: found"
5570 		    " a section in page %p's pv list", __func__, m));
5571 		pte2p = pmap_pte2_quick(pmap, pv->pv_va);
5572 		opte2 = pte2_load(pte2p);
5573 		if (!(opte2 & PTE2_RO)) {
5574 			pte2_store(pte2p, opte2 | PTE2_RO | PTE2_NM);
5575 			if (pte2_is_dirty(opte2))
5576 				vm_page_dirty(m);
5577 			pmap_tlb_flush(pmap, pv->pv_va);
5578 		}
5579 		PMAP_UNLOCK(pmap);
5580 	}
5581 	vm_page_aflag_clear(m, PGA_WRITEABLE);
5582 	sched_unpin();
5583 	rw_wunlock(&pvh_global_lock);
5584 }
5585 
5586 /*
5587  *	Apply the given advice to the specified range of addresses within the
5588  *	given pmap.  Depending on the advice, clear the referenced and/or
5589  *	modified flags in each mapping and set the mapped page's dirty field.
5590  */
5591 void
5592 pmap_advise(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, int advice)
5593 {
5594 	pt1_entry_t *pte1p, opte1;
5595 	pt2_entry_t *pte2p, pte2;
5596 	vm_offset_t pdnxt;
5597 	vm_page_t m;
5598 	boolean_t pv_lists_locked;
5599 
5600 	if (advice != MADV_DONTNEED && advice != MADV_FREE)
5601 		return;
5602 	if (pmap_is_current(pmap))
5603 		pv_lists_locked = FALSE;
5604 	else {
5605 		pv_lists_locked = TRUE;
5606 resume:
5607 		rw_wlock(&pvh_global_lock);
5608 		sched_pin();
5609 	}
5610 	PMAP_LOCK(pmap);
5611 	for (; sva < eva; sva = pdnxt) {
5612 		pdnxt = pte1_trunc(sva + PTE1_SIZE);
5613 		if (pdnxt < sva)
5614 			pdnxt = eva;
5615 		pte1p = pmap_pte1(pmap, sva);
5616 		opte1 = pte1_load(pte1p);
5617 		if (!pte1_is_valid(opte1)) /* XXX */
5618 			continue;
5619 		else if (pte1_is_section(opte1)) {
5620 			if (!pte1_is_managed(opte1))
5621 				continue;
5622 			if (!pv_lists_locked) {
5623 				pv_lists_locked = TRUE;
5624 				if (!rw_try_wlock(&pvh_global_lock)) {
5625 					PMAP_UNLOCK(pmap);
5626 					goto resume;
5627 				}
5628 				sched_pin();
5629 			}
5630 			if (!pmap_demote_pte1(pmap, pte1p, sva)) {
5631 				/*
5632 				 * The large page mapping was destroyed.
5633 				 */
5634 				continue;
5635 			}
5636 
5637 			/*
5638 			 * Unless the page mappings are wired, remove the
5639 			 * mapping to a single page so that a subsequent
5640 			 * access may repromote.  Since the underlying L2 page
5641 			 * table is fully populated, this removal never
5642 			 * frees a L2 page table page.
5643 			 */
5644 			if (!pte1_is_wired(opte1)) {
5645 				pte2p = pmap_pte2_quick(pmap, sva);
5646 				KASSERT(pte2_is_valid(pte2_load(pte2p)),
5647 				    ("%s: invalid PTE2", __func__));
5648 				pmap_remove_pte2(pmap, pte2p, sva, NULL);
5649 			}
5650 		}
5651 		if (pdnxt > eva)
5652 			pdnxt = eva;
5653 		for (pte2p = pmap_pte2_quick(pmap, sva); sva != pdnxt; pte2p++,
5654 		    sva += PAGE_SIZE) {
5655 			pte2 = pte2_load(pte2p);
5656 			if (!pte2_is_valid(pte2) || !pte2_is_managed(pte2))
5657 				continue;
5658 			else if (pte2_is_dirty(pte2)) {
5659 				if (advice == MADV_DONTNEED) {
5660 					/*
5661 					 * Future calls to pmap_is_modified()
5662 					 * can be avoided by making the page
5663 					 * dirty now.
5664 					 */
5665 					m = PHYS_TO_VM_PAGE(pte2_pa(pte2));
5666 					vm_page_dirty(m);
5667 				}
5668 				pte2_set_bit(pte2p, PTE2_NM);
5669 				pte2_clear_bit(pte2p, PTE2_A);
5670 			} else if ((pte2 & PTE2_A) != 0)
5671 				pte2_clear_bit(pte2p, PTE2_A);
5672 			else
5673 				continue;
5674 			pmap_tlb_flush(pmap, sva);
5675 		}
5676 	}
5677 	if (pv_lists_locked) {
5678 		sched_unpin();
5679 		rw_wunlock(&pvh_global_lock);
5680 	}
5681 	PMAP_UNLOCK(pmap);
5682 }
5683 
5684 /*
5685  *	Clear the modify bits on the specified physical page.
5686  */
5687 void
5688 pmap_clear_modify(vm_page_t m)
5689 {
5690 	struct md_page *pvh;
5691 	pv_entry_t next_pv, pv;
5692 	pmap_t pmap;
5693 	pt1_entry_t *pte1p, opte1;
5694 	pt2_entry_t *pte2p, opte2;
5695 	vm_offset_t va;
5696 
5697 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
5698 	    ("%s: page %p is not managed", __func__, m));
5699 	VM_OBJECT_ASSERT_WLOCKED(m->object);
5700 	KASSERT(!vm_page_xbusied(m),
5701 	    ("%s: page %p is exclusive busy", __func__, m));
5702 
5703 	/*
5704 	 * If the page is not PGA_WRITEABLE, then no PTE2s can have PTE2_NM
5705 	 * cleared. If the object containing the page is locked and the page
5706 	 * is not exclusive busied, then PGA_WRITEABLE cannot be concurrently
5707 	 * set.
5708 	 */
5709 	if ((m->flags & PGA_WRITEABLE) == 0)
5710 		return;
5711 	rw_wlock(&pvh_global_lock);
5712 	sched_pin();
5713 	if ((m->flags & PG_FICTITIOUS) != 0)
5714 		goto small_mappings;
5715 	pvh = pa_to_pvh(VM_PAGE_TO_PHYS(m));
5716 	TAILQ_FOREACH_SAFE(pv, &pvh->pv_list, pv_next, next_pv) {
5717 		va = pv->pv_va;
5718 		pmap = PV_PMAP(pv);
5719 		PMAP_LOCK(pmap);
5720 		pte1p = pmap_pte1(pmap, va);
5721 		opte1 = pte1_load(pte1p);
5722 		if (!(opte1 & PTE1_RO)) {
5723 			if (pmap_demote_pte1(pmap, pte1p, va) &&
5724 			    !pte1_is_wired(opte1)) {
5725 				/*
5726 				 * Write protect the mapping to a
5727 				 * single page so that a subsequent
5728 				 * write access may repromote.
5729 				 */
5730 				va += VM_PAGE_TO_PHYS(m) - pte1_pa(opte1);
5731 				pte2p = pmap_pte2_quick(pmap, va);
5732 				opte2 = pte2_load(pte2p);
5733 				if ((opte2 & PTE2_V)) {
5734 					pte2_set_bit(pte2p, PTE2_NM | PTE2_RO);
5735 					vm_page_dirty(m);
5736 					pmap_tlb_flush(pmap, va);
5737 				}
5738 			}
5739 		}
5740 		PMAP_UNLOCK(pmap);
5741 	}
5742 small_mappings:
5743 	TAILQ_FOREACH(pv, &m->md.pv_list, pv_next) {
5744 		pmap = PV_PMAP(pv);
5745 		PMAP_LOCK(pmap);
5746 		pte1p = pmap_pte1(pmap, pv->pv_va);
5747 		KASSERT(!pte1_is_section(pte1_load(pte1p)), ("%s: found"
5748 		    " a section in page %p's pv list", __func__, m));
5749 		pte2p = pmap_pte2_quick(pmap, pv->pv_va);
5750 		if (pte2_is_dirty(pte2_load(pte2p))) {
5751 			pte2_set_bit(pte2p, PTE2_NM);
5752 			pmap_tlb_flush(pmap, pv->pv_va);
5753 		}
5754 		PMAP_UNLOCK(pmap);
5755 	}
5756 	sched_unpin();
5757 	rw_wunlock(&pvh_global_lock);
5758 }
5759 
5760 
5761 /*
5762  *  Sets the memory attribute for the specified page.
5763  */
5764 void
5765 pmap_page_set_memattr(vm_page_t m, vm_memattr_t ma)
5766 {
5767 	pt2_entry_t *cmap2_pte2p;
5768 	vm_memattr_t oma;
5769 	vm_paddr_t pa;
5770 	struct pcpu *pc;
5771 
5772 	oma = m->md.pat_mode;
5773 	m->md.pat_mode = ma;
5774 
5775 	CTR5(KTR_PMAP, "%s: page %p - 0x%08X oma: %d, ma: %d", __func__, m,
5776 	    VM_PAGE_TO_PHYS(m), oma, ma);
5777 	if ((m->flags & PG_FICTITIOUS) != 0)
5778 		return;
5779 #if 0
5780 	/*
5781 	 * If "m" is a normal page, flush it from the cache.
5782 	 *
5783 	 * First, try to find an existing mapping of the page by sf
5784 	 * buffer. sf_buf_invalidate_cache() modifies mapping and
5785 	 * flushes the cache.
5786 	 */
5787 	if (sf_buf_invalidate_cache(m, oma))
5788 		return;
5789 #endif
5790 	/*
5791 	 * If page is not mapped by sf buffer, map the page
5792 	 * transient and do invalidation.
5793 	 */
5794 	if (ma != oma) {
5795 		pa = VM_PAGE_TO_PHYS(m);
5796 		sched_pin();
5797 		pc = get_pcpu();
5798 		cmap2_pte2p = pc->pc_cmap2_pte2p;
5799 		mtx_lock(&pc->pc_cmap_lock);
5800 		if (pte2_load(cmap2_pte2p) != 0)
5801 			panic("%s: CMAP2 busy", __func__);
5802 		pte2_store(cmap2_pte2p, PTE2_KERN_NG(pa, PTE2_AP_KRW,
5803 		    vm_memattr_to_pte2(ma)));
5804 		dcache_wbinv_poc((vm_offset_t)pc->pc_cmap2_addr, pa, PAGE_SIZE);
5805 		pte2_clear(cmap2_pte2p);
5806 		tlb_flush((vm_offset_t)pc->pc_cmap2_addr);
5807 		sched_unpin();
5808 		mtx_unlock(&pc->pc_cmap_lock);
5809 	}
5810 }
5811 
5812 /*
5813  *  Miscellaneous support routines follow
5814  */
5815 
5816 /*
5817  *  Returns TRUE if the given page is mapped individually or as part of
5818  *  a 1mpage.  Otherwise, returns FALSE.
5819  */
5820 boolean_t
5821 pmap_page_is_mapped(vm_page_t m)
5822 {
5823 	boolean_t rv;
5824 
5825 	if ((m->oflags & VPO_UNMANAGED) != 0)
5826 		return (FALSE);
5827 	rw_wlock(&pvh_global_lock);
5828 	rv = !TAILQ_EMPTY(&m->md.pv_list) ||
5829 	    ((m->flags & PG_FICTITIOUS) == 0 &&
5830 	    !TAILQ_EMPTY(&pa_to_pvh(VM_PAGE_TO_PHYS(m))->pv_list));
5831 	rw_wunlock(&pvh_global_lock);
5832 	return (rv);
5833 }
5834 
5835 /*
5836  *  Returns true if the pmap's pv is one of the first
5837  *  16 pvs linked to from this page.  This count may
5838  *  be changed upwards or downwards in the future; it
5839  *  is only necessary that true be returned for a small
5840  *  subset of pmaps for proper page aging.
5841  */
5842 boolean_t
5843 pmap_page_exists_quick(pmap_t pmap, vm_page_t m)
5844 {
5845 	struct md_page *pvh;
5846 	pv_entry_t pv;
5847 	int loops = 0;
5848 	boolean_t rv;
5849 
5850 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
5851 	    ("%s: page %p is not managed", __func__, m));
5852 	rv = FALSE;
5853 	rw_wlock(&pvh_global_lock);
5854 	TAILQ_FOREACH(pv, &m->md.pv_list, pv_next) {
5855 		if (PV_PMAP(pv) == pmap) {
5856 			rv = TRUE;
5857 			break;
5858 		}
5859 		loops++;
5860 		if (loops >= 16)
5861 			break;
5862 	}
5863 	if (!rv && loops < 16 && (m->flags & PG_FICTITIOUS) == 0) {
5864 		pvh = pa_to_pvh(VM_PAGE_TO_PHYS(m));
5865 		TAILQ_FOREACH(pv, &pvh->pv_list, pv_next) {
5866 			if (PV_PMAP(pv) == pmap) {
5867 				rv = TRUE;
5868 				break;
5869 			}
5870 			loops++;
5871 			if (loops >= 16)
5872 				break;
5873 		}
5874 	}
5875 	rw_wunlock(&pvh_global_lock);
5876 	return (rv);
5877 }
5878 
5879 /*
5880  *	pmap_zero_page zeros the specified hardware page by mapping
5881  *	the page into KVM and using bzero to clear its contents.
5882  */
5883 void
5884 pmap_zero_page(vm_page_t m)
5885 {
5886 	pt2_entry_t *cmap2_pte2p;
5887 	struct pcpu *pc;
5888 
5889 	sched_pin();
5890 	pc = get_pcpu();
5891 	cmap2_pte2p = pc->pc_cmap2_pte2p;
5892 	mtx_lock(&pc->pc_cmap_lock);
5893 	if (pte2_load(cmap2_pte2p) != 0)
5894 		panic("%s: CMAP2 busy", __func__);
5895 	pte2_store(cmap2_pte2p, PTE2_KERN_NG(VM_PAGE_TO_PHYS(m), PTE2_AP_KRW,
5896 	    vm_page_pte2_attr(m)));
5897 	pagezero(pc->pc_cmap2_addr);
5898 	pte2_clear(cmap2_pte2p);
5899 	tlb_flush((vm_offset_t)pc->pc_cmap2_addr);
5900 	sched_unpin();
5901 	mtx_unlock(&pc->pc_cmap_lock);
5902 }
5903 
5904 /*
5905  *	pmap_zero_page_area zeros the specified hardware page by mapping
5906  *	the page into KVM and using bzero to clear its contents.
5907  *
5908  *	off and size may not cover an area beyond a single hardware page.
5909  */
5910 void
5911 pmap_zero_page_area(vm_page_t m, int off, int size)
5912 {
5913 	pt2_entry_t *cmap2_pte2p;
5914 	struct pcpu *pc;
5915 
5916 	sched_pin();
5917 	pc = get_pcpu();
5918 	cmap2_pte2p = pc->pc_cmap2_pte2p;
5919 	mtx_lock(&pc->pc_cmap_lock);
5920 	if (pte2_load(cmap2_pte2p) != 0)
5921 		panic("%s: CMAP2 busy", __func__);
5922 	pte2_store(cmap2_pte2p, PTE2_KERN_NG(VM_PAGE_TO_PHYS(m), PTE2_AP_KRW,
5923 	    vm_page_pte2_attr(m)));
5924 	if (off == 0 && size == PAGE_SIZE)
5925 		pagezero(pc->pc_cmap2_addr);
5926 	else
5927 		bzero(pc->pc_cmap2_addr + off, size);
5928 	pte2_clear(cmap2_pte2p);
5929 	tlb_flush((vm_offset_t)pc->pc_cmap2_addr);
5930 	sched_unpin();
5931 	mtx_unlock(&pc->pc_cmap_lock);
5932 }
5933 
5934 /*
5935  *	pmap_copy_page copies the specified (machine independent)
5936  *	page by mapping the page into virtual memory and using
5937  *	bcopy to copy the page, one machine dependent page at a
5938  *	time.
5939  */
5940 void
5941 pmap_copy_page(vm_page_t src, vm_page_t dst)
5942 {
5943 	pt2_entry_t *cmap1_pte2p, *cmap2_pte2p;
5944 	struct pcpu *pc;
5945 
5946 	sched_pin();
5947 	pc = get_pcpu();
5948 	cmap1_pte2p = pc->pc_cmap1_pte2p;
5949 	cmap2_pte2p = pc->pc_cmap2_pte2p;
5950 	mtx_lock(&pc->pc_cmap_lock);
5951 	if (pte2_load(cmap1_pte2p) != 0)
5952 		panic("%s: CMAP1 busy", __func__);
5953 	if (pte2_load(cmap2_pte2p) != 0)
5954 		panic("%s: CMAP2 busy", __func__);
5955 	pte2_store(cmap1_pte2p, PTE2_KERN_NG(VM_PAGE_TO_PHYS(src),
5956 	    PTE2_AP_KR | PTE2_NM, vm_page_pte2_attr(src)));
5957 	pte2_store(cmap2_pte2p, PTE2_KERN_NG(VM_PAGE_TO_PHYS(dst),
5958 	    PTE2_AP_KRW, vm_page_pte2_attr(dst)));
5959 	bcopy(pc->pc_cmap1_addr, pc->pc_cmap2_addr, PAGE_SIZE);
5960 	pte2_clear(cmap1_pte2p);
5961 	tlb_flush((vm_offset_t)pc->pc_cmap1_addr);
5962 	pte2_clear(cmap2_pte2p);
5963 	tlb_flush((vm_offset_t)pc->pc_cmap2_addr);
5964 	sched_unpin();
5965 	mtx_unlock(&pc->pc_cmap_lock);
5966 }
5967 
5968 int unmapped_buf_allowed = 1;
5969 
5970 void
5971 pmap_copy_pages(vm_page_t ma[], vm_offset_t a_offset, vm_page_t mb[],
5972     vm_offset_t b_offset, int xfersize)
5973 {
5974 	pt2_entry_t *cmap1_pte2p, *cmap2_pte2p;
5975 	vm_page_t a_pg, b_pg;
5976 	char *a_cp, *b_cp;
5977 	vm_offset_t a_pg_offset, b_pg_offset;
5978 	struct pcpu *pc;
5979 	int cnt;
5980 
5981 	sched_pin();
5982 	pc = get_pcpu();
5983 	cmap1_pte2p = pc->pc_cmap1_pte2p;
5984 	cmap2_pte2p = pc->pc_cmap2_pte2p;
5985 	mtx_lock(&pc->pc_cmap_lock);
5986 	if (pte2_load(cmap1_pte2p) != 0)
5987 		panic("pmap_copy_pages: CMAP1 busy");
5988 	if (pte2_load(cmap2_pte2p) != 0)
5989 		panic("pmap_copy_pages: CMAP2 busy");
5990 	while (xfersize > 0) {
5991 		a_pg = ma[a_offset >> PAGE_SHIFT];
5992 		a_pg_offset = a_offset & PAGE_MASK;
5993 		cnt = min(xfersize, PAGE_SIZE - a_pg_offset);
5994 		b_pg = mb[b_offset >> PAGE_SHIFT];
5995 		b_pg_offset = b_offset & PAGE_MASK;
5996 		cnt = min(cnt, PAGE_SIZE - b_pg_offset);
5997 		pte2_store(cmap1_pte2p, PTE2_KERN_NG(VM_PAGE_TO_PHYS(a_pg),
5998 		    PTE2_AP_KR | PTE2_NM, vm_page_pte2_attr(a_pg)));
5999 		tlb_flush_local((vm_offset_t)pc->pc_cmap1_addr);
6000 		pte2_store(cmap2_pte2p, PTE2_KERN_NG(VM_PAGE_TO_PHYS(b_pg),
6001 		    PTE2_AP_KRW, vm_page_pte2_attr(b_pg)));
6002 		tlb_flush_local((vm_offset_t)pc->pc_cmap2_addr);
6003 		a_cp = pc->pc_cmap1_addr + a_pg_offset;
6004 		b_cp = pc->pc_cmap2_addr + b_pg_offset;
6005 		bcopy(a_cp, b_cp, cnt);
6006 		a_offset += cnt;
6007 		b_offset += cnt;
6008 		xfersize -= cnt;
6009 	}
6010 	pte2_clear(cmap1_pte2p);
6011 	tlb_flush((vm_offset_t)pc->pc_cmap1_addr);
6012 	pte2_clear(cmap2_pte2p);
6013 	tlb_flush((vm_offset_t)pc->pc_cmap2_addr);
6014 	sched_unpin();
6015 	mtx_unlock(&pc->pc_cmap_lock);
6016 }
6017 
6018 vm_offset_t
6019 pmap_quick_enter_page(vm_page_t m)
6020 {
6021 	struct pcpu *pc;
6022 	pt2_entry_t *pte2p;
6023 
6024 	critical_enter();
6025 	pc = get_pcpu();
6026 	pte2p = pc->pc_qmap_pte2p;
6027 
6028 	KASSERT(pte2_load(pte2p) == 0, ("%s: PTE2 busy", __func__));
6029 
6030 	pte2_store(pte2p, PTE2_KERN_NG(VM_PAGE_TO_PHYS(m), PTE2_AP_KRW,
6031 	    vm_page_pte2_attr(m)));
6032 	return (pc->pc_qmap_addr);
6033 }
6034 
6035 void
6036 pmap_quick_remove_page(vm_offset_t addr)
6037 {
6038 	struct pcpu *pc;
6039 	pt2_entry_t *pte2p;
6040 
6041 	pc = get_pcpu();
6042 	pte2p = pc->pc_qmap_pte2p;
6043 
6044 	KASSERT(addr == pc->pc_qmap_addr, ("%s: invalid address", __func__));
6045 	KASSERT(pte2_load(pte2p) != 0, ("%s: PTE2 not in use", __func__));
6046 
6047 	pte2_clear(pte2p);
6048 	tlb_flush(pc->pc_qmap_addr);
6049 	critical_exit();
6050 }
6051 
6052 /*
6053  *	Copy the range specified by src_addr/len
6054  *	from the source map to the range dst_addr/len
6055  *	in the destination map.
6056  *
6057  *	This routine is only advisory and need not do anything.
6058  */
6059 void
6060 pmap_copy(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr, vm_size_t len,
6061     vm_offset_t src_addr)
6062 {
6063 	struct spglist free;
6064 	vm_offset_t addr;
6065 	vm_offset_t end_addr = src_addr + len;
6066 	vm_offset_t nextva;
6067 
6068 	if (dst_addr != src_addr)
6069 		return;
6070 
6071 	if (!pmap_is_current(src_pmap))
6072 		return;
6073 
6074 	rw_wlock(&pvh_global_lock);
6075 	if (dst_pmap < src_pmap) {
6076 		PMAP_LOCK(dst_pmap);
6077 		PMAP_LOCK(src_pmap);
6078 	} else {
6079 		PMAP_LOCK(src_pmap);
6080 		PMAP_LOCK(dst_pmap);
6081 	}
6082 	sched_pin();
6083 	for (addr = src_addr; addr < end_addr; addr = nextva) {
6084 		pt2_entry_t *src_pte2p, *dst_pte2p;
6085 		vm_page_t dst_mpt2pg, src_mpt2pg;
6086 		pt1_entry_t src_pte1;
6087 		u_int pte1_idx;
6088 
6089 		KASSERT(addr < VM_MAXUSER_ADDRESS,
6090 		    ("%s: invalid to pmap_copy page tables", __func__));
6091 
6092 		nextva = pte1_trunc(addr + PTE1_SIZE);
6093 		if (nextva < addr)
6094 			nextva = end_addr;
6095 
6096 		pte1_idx = pte1_index(addr);
6097 		src_pte1 = src_pmap->pm_pt1[pte1_idx];
6098 		if (pte1_is_section(src_pte1)) {
6099 			if ((addr & PTE1_OFFSET) != 0 ||
6100 			    (addr + PTE1_SIZE) > end_addr)
6101 				continue;
6102 			if (dst_pmap->pm_pt1[pte1_idx] == 0 &&
6103 			    (!pte1_is_managed(src_pte1) ||
6104 			    pmap_pv_insert_pte1(dst_pmap, addr, src_pte1,
6105 			    PMAP_ENTER_NORECLAIM))) {
6106 				dst_pmap->pm_pt1[pte1_idx] = src_pte1 &
6107 				    ~PTE1_W;
6108 				dst_pmap->pm_stats.resident_count +=
6109 				    PTE1_SIZE / PAGE_SIZE;
6110 				pmap_pte1_mappings++;
6111 			}
6112 			continue;
6113 		} else if (!pte1_is_link(src_pte1))
6114 			continue;
6115 
6116 		src_mpt2pg = PHYS_TO_VM_PAGE(pte1_link_pa(src_pte1));
6117 
6118 		/*
6119 		 * We leave PT2s to be linked from PT1 even if they are not
6120 		 * referenced until all PT2s in a page are without reference.
6121 		 *
6122 		 * QQQ: It could be changed ...
6123 		 */
6124 #if 0 /* single_pt2_link_is_cleared */
6125 		KASSERT(pt2_wirecount_get(src_mpt2pg, pte1_idx) > 0,
6126 		    ("%s: source page table page is unused", __func__));
6127 #else
6128 		if (pt2_wirecount_get(src_mpt2pg, pte1_idx) == 0)
6129 			continue;
6130 #endif
6131 		if (nextva > end_addr)
6132 			nextva = end_addr;
6133 
6134 		src_pte2p = pt2map_entry(addr);
6135 		while (addr < nextva) {
6136 			pt2_entry_t temp_pte2;
6137 			temp_pte2 = pte2_load(src_pte2p);
6138 			/*
6139 			 * we only virtual copy managed pages
6140 			 */
6141 			if (pte2_is_managed(temp_pte2)) {
6142 				dst_mpt2pg = pmap_allocpte2(dst_pmap, addr,
6143 				    PMAP_ENTER_NOSLEEP);
6144 				if (dst_mpt2pg == NULL)
6145 					goto out;
6146 				dst_pte2p = pmap_pte2_quick(dst_pmap, addr);
6147 				if (!pte2_is_valid(pte2_load(dst_pte2p)) &&
6148 				    pmap_try_insert_pv_entry(dst_pmap, addr,
6149 				    PHYS_TO_VM_PAGE(pte2_pa(temp_pte2)))) {
6150 					/*
6151 					 * Clear the wired, modified, and
6152 					 * accessed (referenced) bits
6153 					 * during the copy.
6154 					 */
6155 					temp_pte2 &=  ~(PTE2_W | PTE2_A);
6156 					temp_pte2 |= PTE2_NM;
6157 					pte2_store(dst_pte2p, temp_pte2);
6158 					dst_pmap->pm_stats.resident_count++;
6159 				} else {
6160 					SLIST_INIT(&free);
6161 					if (pmap_unwire_pt2(dst_pmap, addr,
6162 					    dst_mpt2pg, &free)) {
6163 						pmap_tlb_flush(dst_pmap, addr);
6164 						vm_page_free_pages_toq(&free,
6165 						    false);
6166 					}
6167 					goto out;
6168 				}
6169 				if (pt2_wirecount_get(dst_mpt2pg, pte1_idx) >=
6170 				    pt2_wirecount_get(src_mpt2pg, pte1_idx))
6171 					break;
6172 			}
6173 			addr += PAGE_SIZE;
6174 			src_pte2p++;
6175 		}
6176 	}
6177 out:
6178 	sched_unpin();
6179 	rw_wunlock(&pvh_global_lock);
6180 	PMAP_UNLOCK(src_pmap);
6181 	PMAP_UNLOCK(dst_pmap);
6182 }
6183 
6184 /*
6185  *	Increase the starting virtual address of the given mapping if a
6186  *	different alignment might result in more section mappings.
6187  */
6188 void
6189 pmap_align_superpage(vm_object_t object, vm_ooffset_t offset,
6190     vm_offset_t *addr, vm_size_t size)
6191 {
6192 	vm_offset_t pte1_offset;
6193 
6194 	if (size < PTE1_SIZE)
6195 		return;
6196 	if (object != NULL && (object->flags & OBJ_COLORED) != 0)
6197 		offset += ptoa(object->pg_color);
6198 	pte1_offset = offset & PTE1_OFFSET;
6199 	if (size - ((PTE1_SIZE - pte1_offset) & PTE1_OFFSET) < PTE1_SIZE ||
6200 	    (*addr & PTE1_OFFSET) == pte1_offset)
6201 		return;
6202 	if ((*addr & PTE1_OFFSET) < pte1_offset)
6203 		*addr = pte1_trunc(*addr) + pte1_offset;
6204 	else
6205 		*addr = pte1_roundup(*addr) + pte1_offset;
6206 }
6207 
6208 void
6209 pmap_activate(struct thread *td)
6210 {
6211 	pmap_t pmap, oldpmap;
6212 	u_int cpuid, ttb;
6213 
6214 	PDEBUG(9, printf("%s: td = %08x\n", __func__, (uint32_t)td));
6215 
6216 	critical_enter();
6217 	pmap = vmspace_pmap(td->td_proc->p_vmspace);
6218 	oldpmap = PCPU_GET(curpmap);
6219 	cpuid = PCPU_GET(cpuid);
6220 
6221 #if defined(SMP)
6222 	CPU_CLR_ATOMIC(cpuid, &oldpmap->pm_active);
6223 	CPU_SET_ATOMIC(cpuid, &pmap->pm_active);
6224 #else
6225 	CPU_CLR(cpuid, &oldpmap->pm_active);
6226 	CPU_SET(cpuid, &pmap->pm_active);
6227 #endif
6228 
6229 	ttb = pmap_ttb_get(pmap);
6230 
6231 	/*
6232 	 * pmap_activate is for the current thread on the current cpu
6233 	 */
6234 	td->td_pcb->pcb_pagedir = ttb;
6235 	cp15_ttbr_set(ttb);
6236 	PCPU_SET(curpmap, pmap);
6237 	critical_exit();
6238 }
6239 
6240 /*
6241  *  Perform the pmap work for mincore.
6242  */
6243 int
6244 pmap_mincore(pmap_t pmap, vm_offset_t addr, vm_paddr_t *locked_pa)
6245 {
6246 	pt1_entry_t *pte1p, pte1;
6247 	pt2_entry_t *pte2p, pte2;
6248 	vm_paddr_t pa;
6249 	bool managed;
6250 	int val;
6251 
6252 	PMAP_LOCK(pmap);
6253 retry:
6254 	pte1p = pmap_pte1(pmap, addr);
6255 	pte1 = pte1_load(pte1p);
6256 	if (pte1_is_section(pte1)) {
6257 		pa = trunc_page(pte1_pa(pte1) | (addr & PTE1_OFFSET));
6258 		managed = pte1_is_managed(pte1);
6259 		val = MINCORE_SUPER | MINCORE_INCORE;
6260 		if (pte1_is_dirty(pte1))
6261 			val |= MINCORE_MODIFIED | MINCORE_MODIFIED_OTHER;
6262 		if (pte1 & PTE1_A)
6263 			val |= MINCORE_REFERENCED | MINCORE_REFERENCED_OTHER;
6264 	} else if (pte1_is_link(pte1)) {
6265 		pte2p = pmap_pte2(pmap, addr);
6266 		pte2 = pte2_load(pte2p);
6267 		pmap_pte2_release(pte2p);
6268 		pa = pte2_pa(pte2);
6269 		managed = pte2_is_managed(pte2);
6270 		val = MINCORE_INCORE;
6271 		if (pte2_is_dirty(pte2))
6272 			val |= MINCORE_MODIFIED | MINCORE_MODIFIED_OTHER;
6273 		if (pte2 & PTE2_A)
6274 			val |= MINCORE_REFERENCED | MINCORE_REFERENCED_OTHER;
6275 	} else {
6276 		managed = false;
6277 		val = 0;
6278 	}
6279 	if ((val & (MINCORE_MODIFIED_OTHER | MINCORE_REFERENCED_OTHER)) !=
6280 	    (MINCORE_MODIFIED_OTHER | MINCORE_REFERENCED_OTHER) && managed) {
6281 		/* Ensure that "PHYS_TO_VM_PAGE(pa)->object" doesn't change. */
6282 		if (vm_page_pa_tryrelock(pmap, pa, locked_pa))
6283 			goto retry;
6284 	} else
6285 		PA_UNLOCK_COND(*locked_pa);
6286 	PMAP_UNLOCK(pmap);
6287 	return (val);
6288 }
6289 
6290 void
6291 pmap_kenter_device(vm_offset_t va, vm_size_t size, vm_paddr_t pa)
6292 {
6293 	vm_offset_t sva;
6294 	uint32_t l2attr;
6295 
6296 	KASSERT((size & PAGE_MASK) == 0,
6297 	    ("%s: device mapping not page-sized", __func__));
6298 
6299 	sva = va;
6300 	l2attr = vm_memattr_to_pte2(VM_MEMATTR_DEVICE);
6301 	while (size != 0) {
6302 		pmap_kenter_prot_attr(va, pa, PTE2_AP_KRW, l2attr);
6303 		va += PAGE_SIZE;
6304 		pa += PAGE_SIZE;
6305 		size -= PAGE_SIZE;
6306 	}
6307 	tlb_flush_range(sva, va - sva);
6308 }
6309 
6310 void
6311 pmap_kremove_device(vm_offset_t va, vm_size_t size)
6312 {
6313 	vm_offset_t sva;
6314 
6315 	KASSERT((size & PAGE_MASK) == 0,
6316 	    ("%s: device mapping not page-sized", __func__));
6317 
6318 	sva = va;
6319 	while (size != 0) {
6320 		pmap_kremove(va);
6321 		va += PAGE_SIZE;
6322 		size -= PAGE_SIZE;
6323 	}
6324 	tlb_flush_range(sva, va - sva);
6325 }
6326 
6327 void
6328 pmap_set_pcb_pagedir(pmap_t pmap, struct pcb *pcb)
6329 {
6330 
6331 	pcb->pcb_pagedir = pmap_ttb_get(pmap);
6332 }
6333 
6334 
6335 /*
6336  *  Clean L1 data cache range by physical address.
6337  *  The range must be within a single page.
6338  */
6339 static void
6340 pmap_dcache_wb_pou(vm_paddr_t pa, vm_size_t size, uint32_t attr)
6341 {
6342 	pt2_entry_t *cmap2_pte2p;
6343 	struct pcpu *pc;
6344 
6345 	KASSERT(((pa & PAGE_MASK) + size) <= PAGE_SIZE,
6346 	    ("%s: not on single page", __func__));
6347 
6348 	sched_pin();
6349 	pc = get_pcpu();
6350 	cmap2_pte2p = pc->pc_cmap2_pte2p;
6351 	mtx_lock(&pc->pc_cmap_lock);
6352 	if (pte2_load(cmap2_pte2p) != 0)
6353 		panic("%s: CMAP2 busy", __func__);
6354 	pte2_store(cmap2_pte2p, PTE2_KERN_NG(pa, PTE2_AP_KRW, attr));
6355 	dcache_wb_pou((vm_offset_t)pc->pc_cmap2_addr + (pa & PAGE_MASK), size);
6356 	pte2_clear(cmap2_pte2p);
6357 	tlb_flush((vm_offset_t)pc->pc_cmap2_addr);
6358 	sched_unpin();
6359 	mtx_unlock(&pc->pc_cmap_lock);
6360 }
6361 
6362 /*
6363  *  Sync instruction cache range which is not mapped yet.
6364  */
6365 void
6366 cache_icache_sync_fresh(vm_offset_t va, vm_paddr_t pa, vm_size_t size)
6367 {
6368 	uint32_t len, offset;
6369 	vm_page_t m;
6370 
6371 	/* Write back d-cache on given address range. */
6372 	offset = pa & PAGE_MASK;
6373 	for ( ; size != 0; size -= len, pa += len, offset = 0) {
6374 		len = min(PAGE_SIZE - offset, size);
6375 		m = PHYS_TO_VM_PAGE(pa);
6376 		KASSERT(m != NULL, ("%s: vm_page_t is null for %#x",
6377 		  __func__, pa));
6378 		pmap_dcache_wb_pou(pa, len, vm_page_pte2_attr(m));
6379 	}
6380 	/*
6381 	 * I-cache is VIPT. Only way how to flush all virtual mappings
6382 	 * on given physical address is to invalidate all i-cache.
6383 	 */
6384 	icache_inv_all();
6385 }
6386 
6387 void
6388 pmap_sync_icache(pmap_t pmap, vm_offset_t va, vm_size_t size)
6389 {
6390 
6391 	/* Write back d-cache on given address range. */
6392 	if (va >= VM_MIN_KERNEL_ADDRESS) {
6393 		dcache_wb_pou(va, size);
6394 	} else {
6395 		uint32_t len, offset;
6396 		vm_paddr_t pa;
6397 		vm_page_t m;
6398 
6399 		offset = va & PAGE_MASK;
6400 		for ( ; size != 0; size -= len, va += len, offset = 0) {
6401 			pa = pmap_extract(pmap, va); /* offset is preserved */
6402 			len = min(PAGE_SIZE - offset, size);
6403 			m = PHYS_TO_VM_PAGE(pa);
6404 			KASSERT(m != NULL, ("%s: vm_page_t is null for %#x",
6405 				__func__, pa));
6406 			pmap_dcache_wb_pou(pa, len, vm_page_pte2_attr(m));
6407 		}
6408 	}
6409 	/*
6410 	 * I-cache is VIPT. Only way how to flush all virtual mappings
6411 	 * on given physical address is to invalidate all i-cache.
6412 	 */
6413 	icache_inv_all();
6414 }
6415 
6416 /*
6417  *  The implementation of pmap_fault() uses IN_RANGE2() macro which
6418  *  depends on the fact that given range size is a power of 2.
6419  */
6420 CTASSERT(powerof2(NB_IN_PT1));
6421 CTASSERT(powerof2(PT2MAP_SIZE));
6422 
6423 #define IN_RANGE2(addr, start, size)	\
6424     ((vm_offset_t)(start) == ((vm_offset_t)(addr) & ~((size) - 1)))
6425 
6426 /*
6427  *  Handle access and R/W emulation faults.
6428  */
6429 int
6430 pmap_fault(pmap_t pmap, vm_offset_t far, uint32_t fsr, int idx, bool usermode)
6431 {
6432 	pt1_entry_t *pte1p, pte1;
6433 	pt2_entry_t *pte2p, pte2;
6434 
6435 	if (pmap == NULL)
6436 		pmap = kernel_pmap;
6437 
6438 	/*
6439 	 * In kernel, we should never get abort with FAR which is in range of
6440 	 * pmap->pm_pt1 or PT2MAP address spaces. If it happens, stop here
6441 	 * and print out a useful abort message and even get to the debugger
6442 	 * otherwise it likely ends with never ending loop of aborts.
6443 	 */
6444 	if (__predict_false(IN_RANGE2(far, pmap->pm_pt1, NB_IN_PT1))) {
6445 		/*
6446 		 * All L1 tables should always be mapped and present.
6447 		 * However, we check only current one herein. For user mode,
6448 		 * only permission abort from malicious user is not fatal.
6449 		 * And alignment abort as it may have higher priority.
6450 		 */
6451 		if (!usermode || (idx != FAULT_ALIGN && idx != FAULT_PERM_L2)) {
6452 			CTR4(KTR_PMAP, "%s: pmap %#x pm_pt1 %#x far %#x",
6453 			    __func__, pmap, pmap->pm_pt1, far);
6454 			panic("%s: pm_pt1 abort", __func__);
6455 		}
6456 		return (KERN_INVALID_ADDRESS);
6457 	}
6458 	if (__predict_false(IN_RANGE2(far, PT2MAP, PT2MAP_SIZE))) {
6459 		/*
6460 		 * PT2MAP should be always mapped and present in current
6461 		 * L1 table. However, only existing L2 tables are mapped
6462 		 * in PT2MAP. For user mode, only L2 translation abort and
6463 		 * permission abort from malicious user is not fatal.
6464 		 * And alignment abort as it may have higher priority.
6465 		 */
6466 		if (!usermode || (idx != FAULT_ALIGN &&
6467 		    idx != FAULT_TRAN_L2 && idx != FAULT_PERM_L2)) {
6468 			CTR4(KTR_PMAP, "%s: pmap %#x PT2MAP %#x far %#x",
6469 			    __func__, pmap, PT2MAP, far);
6470 			panic("%s: PT2MAP abort", __func__);
6471 		}
6472 		return (KERN_INVALID_ADDRESS);
6473 	}
6474 
6475 	/*
6476 	 * A pmap lock is used below for handling of access and R/W emulation
6477 	 * aborts. They were handled by atomic operations before so some
6478 	 * analysis of new situation is needed to answer the following question:
6479 	 * Is it safe to use the lock even for these aborts?
6480 	 *
6481 	 * There may happen two cases in general:
6482 	 *
6483 	 * (1) Aborts while the pmap lock is locked already - this should not
6484 	 * happen as pmap lock is not recursive. However, under pmap lock only
6485 	 * internal kernel data should be accessed and such data should be
6486 	 * mapped with A bit set and NM bit cleared. If double abort happens,
6487 	 * then a mapping of data which has caused it must be fixed. Further,
6488 	 * all new mappings are always made with A bit set and the bit can be
6489 	 * cleared only on managed mappings.
6490 	 *
6491 	 * (2) Aborts while another lock(s) is/are locked - this already can
6492 	 * happen. However, there is no difference here if it's either access or
6493 	 * R/W emulation abort, or if it's some other abort.
6494 	 */
6495 
6496 	PMAP_LOCK(pmap);
6497 #ifdef INVARIANTS
6498 	pte1 = pte1_load(pmap_pte1(pmap, far));
6499 	if (pte1_is_link(pte1)) {
6500 		/*
6501 		 * Check in advance that associated L2 page table is mapped into
6502 		 * PT2MAP space. Note that faulty access to not mapped L2 page
6503 		 * table is caught in more general check above where "far" is
6504 		 * checked that it does not lay in PT2MAP space. Note also that
6505 		 * L1 page table and PT2TAB always exist and are mapped.
6506 		 */
6507 		pte2 = pt2tab_load(pmap_pt2tab_entry(pmap, far));
6508 		if (!pte2_is_valid(pte2))
6509 			panic("%s: missing L2 page table (%p, %#x)",
6510 			    __func__, pmap, far);
6511 	}
6512 #endif
6513 #ifdef SMP
6514 	/*
6515 	 * Special treatment is due to break-before-make approach done when
6516 	 * pte1 is updated for userland mapping during section promotion or
6517 	 * demotion. If not caught here, pmap_enter() can find a section
6518 	 * mapping on faulting address. That is not allowed.
6519 	 */
6520 	if (idx == FAULT_TRAN_L1 && usermode && cp15_ats1cur_check(far) == 0) {
6521 		PMAP_UNLOCK(pmap);
6522 		return (KERN_SUCCESS);
6523 	}
6524 #endif
6525 	/*
6526 	 * Accesss bits for page and section. Note that the entry
6527 	 * is not in TLB yet, so TLB flush is not necessary.
6528 	 *
6529 	 * QQQ: This is hardware emulation, we do not call userret()
6530 	 *      for aborts from user mode.
6531 	 */
6532 	if (idx == FAULT_ACCESS_L2) {
6533 		pte1 = pte1_load(pmap_pte1(pmap, far));
6534 		if (pte1_is_link(pte1)) {
6535 			/* L2 page table should exist and be mapped. */
6536 			pte2p = pt2map_entry(far);
6537 			pte2 = pte2_load(pte2p);
6538 			if (pte2_is_valid(pte2)) {
6539 				pte2_store(pte2p, pte2 | PTE2_A);
6540 				PMAP_UNLOCK(pmap);
6541 				return (KERN_SUCCESS);
6542 			}
6543 		} else {
6544 			/*
6545 			 * We got L2 access fault but PTE1 is not a link.
6546 			 * Probably some race happened, do nothing.
6547 			 */
6548 			CTR3(KTR_PMAP, "%s: FAULT_ACCESS_L2 - pmap %#x far %#x",
6549 			    __func__, pmap, far);
6550 			PMAP_UNLOCK(pmap);
6551 			return (KERN_SUCCESS);
6552 		}
6553 	}
6554 	if (idx == FAULT_ACCESS_L1) {
6555 		pte1p = pmap_pte1(pmap, far);
6556 		pte1 = pte1_load(pte1p);
6557 		if (pte1_is_section(pte1)) {
6558 			pte1_store(pte1p, pte1 | PTE1_A);
6559 			PMAP_UNLOCK(pmap);
6560 			return (KERN_SUCCESS);
6561 		} else {
6562 			/*
6563 			 * We got L1 access fault but PTE1 is not section
6564 			 * mapping. Probably some race happened, do nothing.
6565 			 */
6566 			CTR3(KTR_PMAP, "%s: FAULT_ACCESS_L1 - pmap %#x far %#x",
6567 			    __func__, pmap, far);
6568 			PMAP_UNLOCK(pmap);
6569 			return (KERN_SUCCESS);
6570 		}
6571 	}
6572 
6573 	/*
6574 	 * Handle modify bits for page and section. Note that the modify
6575 	 * bit is emulated by software. So PTEx_RO is software read only
6576 	 * bit and PTEx_NM flag is real hardware read only bit.
6577 	 *
6578 	 * QQQ: This is hardware emulation, we do not call userret()
6579 	 *      for aborts from user mode.
6580 	 */
6581 	if ((fsr & FSR_WNR) && (idx == FAULT_PERM_L2)) {
6582 		pte1 = pte1_load(pmap_pte1(pmap, far));
6583 		if (pte1_is_link(pte1)) {
6584 			/* L2 page table should exist and be mapped. */
6585 			pte2p = pt2map_entry(far);
6586 			pte2 = pte2_load(pte2p);
6587 			if (pte2_is_valid(pte2) && !(pte2 & PTE2_RO) &&
6588 			    (pte2 & PTE2_NM)) {
6589 				pte2_store(pte2p, pte2 & ~PTE2_NM);
6590 				tlb_flush(trunc_page(far));
6591 				PMAP_UNLOCK(pmap);
6592 				return (KERN_SUCCESS);
6593 			}
6594 		} else {
6595 			/*
6596 			 * We got L2 permission fault but PTE1 is not a link.
6597 			 * Probably some race happened, do nothing.
6598 			 */
6599 			CTR3(KTR_PMAP, "%s: FAULT_PERM_L2 - pmap %#x far %#x",
6600 			    __func__, pmap, far);
6601 			PMAP_UNLOCK(pmap);
6602 			return (KERN_SUCCESS);
6603 		}
6604 	}
6605 	if ((fsr & FSR_WNR) && (idx == FAULT_PERM_L1)) {
6606 		pte1p = pmap_pte1(pmap, far);
6607 		pte1 = pte1_load(pte1p);
6608 		if (pte1_is_section(pte1)) {
6609 			if (!(pte1 & PTE1_RO) && (pte1 & PTE1_NM)) {
6610 				pte1_store(pte1p, pte1 & ~PTE1_NM);
6611 				tlb_flush(pte1_trunc(far));
6612 				PMAP_UNLOCK(pmap);
6613 				return (KERN_SUCCESS);
6614 			}
6615 		} else {
6616 			/*
6617 			 * We got L1 permission fault but PTE1 is not section
6618 			 * mapping. Probably some race happened, do nothing.
6619 			 */
6620 			CTR3(KTR_PMAP, "%s: FAULT_PERM_L1 - pmap %#x far %#x",
6621 			    __func__, pmap, far);
6622 			PMAP_UNLOCK(pmap);
6623 			return (KERN_SUCCESS);
6624 		}
6625 	}
6626 
6627 	/*
6628 	 * QQQ: The previous code, mainly fast handling of access and
6629 	 *      modify bits aborts, could be moved to ASM. Now we are
6630 	 *      starting to deal with not fast aborts.
6631 	 */
6632 	PMAP_UNLOCK(pmap);
6633 	return (KERN_FAILURE);
6634 }
6635 
6636 #if defined(PMAP_DEBUG)
6637 /*
6638  *  Reusing of KVA used in pmap_zero_page function !!!
6639  */
6640 static void
6641 pmap_zero_page_check(vm_page_t m)
6642 {
6643 	pt2_entry_t *cmap2_pte2p;
6644 	uint32_t *p, *end;
6645 	struct pcpu *pc;
6646 
6647 	sched_pin();
6648 	pc = get_pcpu();
6649 	cmap2_pte2p = pc->pc_cmap2_pte2p;
6650 	mtx_lock(&pc->pc_cmap_lock);
6651 	if (pte2_load(cmap2_pte2p) != 0)
6652 		panic("%s: CMAP2 busy", __func__);
6653 	pte2_store(cmap2_pte2p, PTE2_KERN_NG(VM_PAGE_TO_PHYS(m), PTE2_AP_KRW,
6654 	    vm_page_pte2_attr(m)));
6655 	end = (uint32_t*)(pc->pc_cmap2_addr + PAGE_SIZE);
6656 	for (p = (uint32_t*)pc->pc_cmap2_addr; p < end; p++)
6657 		if (*p != 0)
6658 			panic("%s: page %p not zero, va: %p", __func__, m,
6659 			    pc->pc_cmap2_addr);
6660 	pte2_clear(cmap2_pte2p);
6661 	tlb_flush((vm_offset_t)pc->pc_cmap2_addr);
6662 	sched_unpin();
6663 	mtx_unlock(&pc->pc_cmap_lock);
6664 }
6665 
6666 int
6667 pmap_pid_dump(int pid)
6668 {
6669 	pmap_t pmap;
6670 	struct proc *p;
6671 	int npte2 = 0;
6672 	int i, j, index;
6673 
6674 	sx_slock(&allproc_lock);
6675 	FOREACH_PROC_IN_SYSTEM(p) {
6676 		if (p->p_pid != pid || p->p_vmspace == NULL)
6677 			continue;
6678 		index = 0;
6679 		pmap = vmspace_pmap(p->p_vmspace);
6680 		for (i = 0; i < NPTE1_IN_PT1; i++) {
6681 			pt1_entry_t pte1;
6682 			pt2_entry_t *pte2p, pte2;
6683 			vm_offset_t base, va;
6684 			vm_paddr_t pa;
6685 			vm_page_t m;
6686 
6687 			base = i << PTE1_SHIFT;
6688 			pte1 = pte1_load(&pmap->pm_pt1[i]);
6689 
6690 			if (pte1_is_section(pte1)) {
6691 				/*
6692 				 * QQQ: Do something here!
6693 				 */
6694 			} else if (pte1_is_link(pte1)) {
6695 				for (j = 0; j < NPTE2_IN_PT2; j++) {
6696 					va = base + (j << PAGE_SHIFT);
6697 					if (va >= VM_MIN_KERNEL_ADDRESS) {
6698 						if (index) {
6699 							index = 0;
6700 							printf("\n");
6701 						}
6702 						sx_sunlock(&allproc_lock);
6703 						return (npte2);
6704 					}
6705 					pte2p = pmap_pte2(pmap, va);
6706 					pte2 = pte2_load(pte2p);
6707 					pmap_pte2_release(pte2p);
6708 					if (!pte2_is_valid(pte2))
6709 						continue;
6710 
6711 					pa = pte2_pa(pte2);
6712 					m = PHYS_TO_VM_PAGE(pa);
6713 					printf("va: 0x%x, pa: 0x%x, h: %d, w:"
6714 					    " %d, f: 0x%x", va, pa,
6715 					    m->hold_count, m->wire_count,
6716 					    m->flags);
6717 					npte2++;
6718 					index++;
6719 					if (index >= 2) {
6720 						index = 0;
6721 						printf("\n");
6722 					} else {
6723 						printf(" ");
6724 					}
6725 				}
6726 			}
6727 		}
6728 	}
6729 	sx_sunlock(&allproc_lock);
6730 	return (npte2);
6731 }
6732 
6733 #endif
6734 
6735 #ifdef DDB
6736 static pt2_entry_t *
6737 pmap_pte2_ddb(pmap_t pmap, vm_offset_t va)
6738 {
6739 	pt1_entry_t pte1;
6740 	vm_paddr_t pt2pg_pa;
6741 
6742 	pte1 = pte1_load(pmap_pte1(pmap, va));
6743 	if (!pte1_is_link(pte1))
6744 		return (NULL);
6745 
6746 	if (pmap_is_current(pmap))
6747 		return (pt2map_entry(va));
6748 
6749 	/* Note that L2 page table size is not equal to PAGE_SIZE. */
6750 	pt2pg_pa = trunc_page(pte1_link_pa(pte1));
6751 	if (pte2_pa(pte2_load(PMAP3)) != pt2pg_pa) {
6752 		pte2_store(PMAP3, PTE2_KPT(pt2pg_pa));
6753 #ifdef SMP
6754 		PMAP3cpu = PCPU_GET(cpuid);
6755 #endif
6756 		tlb_flush_local((vm_offset_t)PADDR3);
6757 	}
6758 #ifdef SMP
6759 	else if (PMAP3cpu != PCPU_GET(cpuid)) {
6760 		PMAP3cpu = PCPU_GET(cpuid);
6761 		tlb_flush_local((vm_offset_t)PADDR3);
6762 	}
6763 #endif
6764 	return (PADDR3 + (arm32_btop(va) & (NPTE2_IN_PG - 1)));
6765 }
6766 
6767 static void
6768 dump_pmap(pmap_t pmap)
6769 {
6770 
6771 	printf("pmap %p\n", pmap);
6772 	printf("  pm_pt1: %p\n", pmap->pm_pt1);
6773 	printf("  pm_pt2tab: %p\n", pmap->pm_pt2tab);
6774 	printf("  pm_active: 0x%08lX\n", pmap->pm_active.__bits[0]);
6775 }
6776 
6777 DB_SHOW_COMMAND(pmaps, pmap_list_pmaps)
6778 {
6779 
6780 	pmap_t pmap;
6781 	LIST_FOREACH(pmap, &allpmaps, pm_list) {
6782 		dump_pmap(pmap);
6783 	}
6784 }
6785 
6786 static int
6787 pte2_class(pt2_entry_t pte2)
6788 {
6789 	int cls;
6790 
6791 	cls = (pte2 >> 2) & 0x03;
6792 	cls |= (pte2 >> 4) & 0x04;
6793 	return (cls);
6794 }
6795 
6796 static void
6797 dump_section(pmap_t pmap, uint32_t pte1_idx)
6798 {
6799 }
6800 
6801 static void
6802 dump_link(pmap_t pmap, uint32_t pte1_idx, boolean_t invalid_ok)
6803 {
6804 	uint32_t i;
6805 	vm_offset_t va;
6806 	pt2_entry_t *pte2p, pte2;
6807 	vm_page_t m;
6808 
6809 	va = pte1_idx << PTE1_SHIFT;
6810 	pte2p = pmap_pte2_ddb(pmap, va);
6811 	for (i = 0; i < NPTE2_IN_PT2; i++, pte2p++, va += PAGE_SIZE) {
6812 		pte2 = pte2_load(pte2p);
6813 		if (pte2 == 0)
6814 			continue;
6815 		if (!pte2_is_valid(pte2)) {
6816 			printf(" 0x%08X: 0x%08X", va, pte2);
6817 			if (!invalid_ok)
6818 				printf(" - not valid !!!");
6819 			printf("\n");
6820 			continue;
6821 		}
6822 		m = PHYS_TO_VM_PAGE(pte2_pa(pte2));
6823 		printf(" 0x%08X: 0x%08X, TEX%d, s:%d, g:%d, m:%p", va , pte2,
6824 		    pte2_class(pte2), !!(pte2 & PTE2_S), !(pte2 & PTE2_NG), m);
6825 		if (m != NULL) {
6826 			printf(" v:%d h:%d w:%d f:0x%04X\n", m->valid,
6827 			    m->hold_count, m->wire_count, m->flags);
6828 		} else {
6829 			printf("\n");
6830 		}
6831 	}
6832 }
6833 
6834 static __inline boolean_t
6835 is_pv_chunk_space(vm_offset_t va)
6836 {
6837 
6838 	if ((((vm_offset_t)pv_chunkbase) <= va) &&
6839 	    (va < ((vm_offset_t)pv_chunkbase + PAGE_SIZE * pv_maxchunks)))
6840 		return (TRUE);
6841 	return (FALSE);
6842 }
6843 
6844 DB_SHOW_COMMAND(pmap, pmap_pmap_print)
6845 {
6846 	/* XXX convert args. */
6847 	pmap_t pmap = (pmap_t)addr;
6848 	pt1_entry_t pte1;
6849 	pt2_entry_t pte2;
6850 	vm_offset_t va, eva;
6851 	vm_page_t m;
6852 	uint32_t i;
6853 	boolean_t invalid_ok, dump_link_ok, dump_pv_chunk;
6854 
6855 	if (have_addr) {
6856 		pmap_t pm;
6857 
6858 		LIST_FOREACH(pm, &allpmaps, pm_list)
6859 			if (pm == pmap) break;
6860 		if (pm == NULL) {
6861 			printf("given pmap %p is not in allpmaps list\n", pmap);
6862 			return;
6863 		}
6864 	} else
6865 		pmap = PCPU_GET(curpmap);
6866 
6867 	eva = (modif[0] == 'u') ? VM_MAXUSER_ADDRESS : 0xFFFFFFFF;
6868 	dump_pv_chunk = FALSE; /* XXX evaluate from modif[] */
6869 
6870 	printf("pmap: 0x%08X\n", (uint32_t)pmap);
6871 	printf("PT2MAP: 0x%08X\n", (uint32_t)PT2MAP);
6872 	printf("pt2tab: 0x%08X\n", (uint32_t)pmap->pm_pt2tab);
6873 
6874 	for(i = 0; i < NPTE1_IN_PT1; i++) {
6875 		pte1 = pte1_load(&pmap->pm_pt1[i]);
6876 		if (pte1 == 0)
6877 			continue;
6878 		va = i << PTE1_SHIFT;
6879 		if (va >= eva)
6880 			break;
6881 
6882 		if (pte1_is_section(pte1)) {
6883 			printf("0x%08X: Section 0x%08X, s:%d g:%d\n", va, pte1,
6884 			    !!(pte1 & PTE1_S), !(pte1 & PTE1_NG));
6885 			dump_section(pmap, i);
6886 		} else if (pte1_is_link(pte1)) {
6887 			dump_link_ok = TRUE;
6888 			invalid_ok = FALSE;
6889 			pte2 = pte2_load(pmap_pt2tab_entry(pmap, va));
6890 			m = PHYS_TO_VM_PAGE(pte1_link_pa(pte1));
6891 			printf("0x%08X: Link 0x%08X, pt2tab: 0x%08X m: %p",
6892 			    va, pte1, pte2, m);
6893 			if (is_pv_chunk_space(va)) {
6894 				printf(" - pv_chunk space");
6895 				if (dump_pv_chunk)
6896 					invalid_ok = TRUE;
6897 				else
6898 					dump_link_ok = FALSE;
6899 			}
6900 			else if (m != NULL)
6901 				printf(" w:%d w2:%u", m->wire_count,
6902 				    pt2_wirecount_get(m, pte1_index(va)));
6903 			if (pte2 == 0)
6904 				printf(" !!! pt2tab entry is ZERO");
6905 			else if (pte2_pa(pte1) != pte2_pa(pte2))
6906 				printf(" !!! pt2tab entry is DIFFERENT - m: %p",
6907 				    PHYS_TO_VM_PAGE(pte2_pa(pte2)));
6908 			printf("\n");
6909 			if (dump_link_ok)
6910 				dump_link(pmap, i, invalid_ok);
6911 		} else
6912 			printf("0x%08X: Invalid entry 0x%08X\n", va, pte1);
6913 	}
6914 }
6915 
6916 static void
6917 dump_pt2tab(pmap_t pmap)
6918 {
6919 	uint32_t i;
6920 	pt2_entry_t pte2;
6921 	vm_offset_t va;
6922 	vm_paddr_t pa;
6923 	vm_page_t m;
6924 
6925 	printf("PT2TAB:\n");
6926 	for (i = 0; i < PT2TAB_ENTRIES; i++) {
6927 		pte2 = pte2_load(&pmap->pm_pt2tab[i]);
6928 		if (!pte2_is_valid(pte2))
6929 			continue;
6930 		va = i << PT2TAB_SHIFT;
6931 		pa = pte2_pa(pte2);
6932 		m = PHYS_TO_VM_PAGE(pa);
6933 		printf(" 0x%08X: 0x%08X, TEX%d, s:%d, m:%p", va, pte2,
6934 		    pte2_class(pte2), !!(pte2 & PTE2_S), m);
6935 		if (m != NULL)
6936 			printf(" , h: %d, w: %d, f: 0x%04X pidx: %lld",
6937 			    m->hold_count, m->wire_count, m->flags, m->pindex);
6938 		printf("\n");
6939 	}
6940 }
6941 
6942 DB_SHOW_COMMAND(pmap_pt2tab, pmap_pt2tab_print)
6943 {
6944 	/* XXX convert args. */
6945 	pmap_t pmap = (pmap_t)addr;
6946 	pt1_entry_t pte1;
6947 	pt2_entry_t pte2;
6948 	vm_offset_t va;
6949 	uint32_t i, start;
6950 
6951 	if (have_addr) {
6952 		printf("supported only on current pmap\n");
6953 		return;
6954 	}
6955 
6956 	pmap = PCPU_GET(curpmap);
6957 	printf("curpmap: 0x%08X\n", (uint32_t)pmap);
6958 	printf("PT2MAP: 0x%08X\n", (uint32_t)PT2MAP);
6959 	printf("pt2tab: 0x%08X\n", (uint32_t)pmap->pm_pt2tab);
6960 
6961 	start = pte1_index((vm_offset_t)PT2MAP);
6962 	for (i = start; i < (start + NPT2_IN_PT2TAB); i++) {
6963 		pte1 = pte1_load(&pmap->pm_pt1[i]);
6964 		if (pte1 == 0)
6965 			continue;
6966 		va = i << PTE1_SHIFT;
6967 		if (pte1_is_section(pte1)) {
6968 			printf("0x%08X: Section 0x%08X, s:%d\n", va, pte1,
6969 			    !!(pte1 & PTE1_S));
6970 			dump_section(pmap, i);
6971 		} else if (pte1_is_link(pte1)) {
6972 			pte2 = pte2_load(pmap_pt2tab_entry(pmap, va));
6973 			printf("0x%08X: Link 0x%08X, pt2tab: 0x%08X\n", va,
6974 			    pte1, pte2);
6975 			if (pte2 == 0)
6976 				printf("  !!! pt2tab entry is ZERO\n");
6977 		} else
6978 			printf("0x%08X: Invalid entry 0x%08X\n", va, pte1);
6979 	}
6980 	dump_pt2tab(pmap);
6981 }
6982 #endif
6983