xref: /illumos-gate/usr/src/uts/i86pc/vm/hat_i86.c (revision 7417cfdecea1902cef03c0d61a72df97d945925d)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright (c) 1992, 2010, Oracle and/or its affiliates. All rights reserved.
23  */
24 /*
25  * Copyright (c) 2010, Intel Corporation.
26  * All rights reserved.
27  */
28 
29 
30 /*
31  * VM - Hardware Address Translation management for i386 and amd64
32  *
33  * Implementation of the interfaces described in <common/vm/hat.h>
34  *
35  * Nearly all the details of how the hardware is managed should not be
36  * visible outside this layer except for misc. machine specific functions
37  * that work in conjunction with this code.
38  *
39  * Routines used only inside of i86pc/vm start with hati_ for HAT Internal.
40  */
41 
42 #include <sys/machparam.h>
43 #include <sys/machsystm.h>
44 #include <sys/mman.h>
45 #include <sys/types.h>
46 #include <sys/systm.h>
47 #include <sys/cpuvar.h>
48 #include <sys/thread.h>
49 #include <sys/proc.h>
50 #include <sys/cpu.h>
51 #include <sys/kmem.h>
52 #include <sys/disp.h>
53 #include <sys/shm.h>
54 #include <sys/sysmacros.h>
55 #include <sys/machparam.h>
56 #include <sys/vmem.h>
57 #include <sys/vmsystm.h>
58 #include <sys/promif.h>
59 #include <sys/var.h>
60 #include <sys/x86_archext.h>
61 #include <sys/atomic.h>
62 #include <sys/bitmap.h>
63 #include <sys/controlregs.h>
64 #include <sys/bootconf.h>
65 #include <sys/bootsvcs.h>
66 #include <sys/bootinfo.h>
67 #include <sys/archsystm.h>
68 
69 #include <vm/seg_kmem.h>
70 #include <vm/hat_i86.h>
71 #include <vm/as.h>
72 #include <vm/seg.h>
73 #include <vm/page.h>
74 #include <vm/seg_kp.h>
75 #include <vm/seg_kpm.h>
76 #include <vm/vm_dep.h>
77 #ifdef __xpv
78 #include <sys/hypervisor.h>
79 #endif
80 #include <vm/kboot_mmu.h>
81 #include <vm/seg_spt.h>
82 
83 #include <sys/cmn_err.h>
84 
85 /*
86  * Basic parameters for hat operation.
87  */
88 struct hat_mmu_info mmu;
89 
90 /*
91  * The page that is the kernel's top level pagetable.
92  *
93  * For 32 bit PAE support on i86pc, the kernel hat will use the 1st 4 entries
94  * on this 4K page for its top level page table. The remaining groups of
95  * 4 entries are used for per processor copies of user VLP pagetables for
96  * running threads.  See hat_switch() and reload_pae32() for details.
97  *
98  * vlp_page[0..3] - level==2 PTEs for kernel HAT
99  * vlp_page[4..7] - level==2 PTEs for user thread on cpu 0
100  * vlp_page[8..11]  - level==2 PTE for user thread on cpu 1
101  * etc...
102  */
103 static x86pte_t *vlp_page;
104 
105 /*
106  * forward declaration of internal utility routines
107  */
108 static x86pte_t hati_update_pte(htable_t *ht, uint_t entry, x86pte_t expected,
109 	x86pte_t new);
110 
111 /*
112  * The kernel address space exists in all HATs. To implement this the
113  * kernel reserves a fixed number of entries in the topmost level(s) of page
114  * tables. The values are setup during startup and then copied to every user
115  * hat created by hat_alloc(). This means that kernelbase must be:
116  *
117  *	  4Meg aligned for 32 bit kernels
118  *	512Gig aligned for x86_64 64 bit kernel
119  *
120  * The hat_kernel_range_ts describe what needs to be copied from kernel hat
121  * to each user hat.
122  */
123 typedef struct hat_kernel_range {
124 	level_t		hkr_level;
125 	uintptr_t	hkr_start_va;
126 	uintptr_t	hkr_end_va;	/* zero means to end of memory */
127 } hat_kernel_range_t;
128 #define	NUM_KERNEL_RANGE 2
129 static hat_kernel_range_t kernel_ranges[NUM_KERNEL_RANGE];
130 static int num_kernel_ranges;
131 
132 uint_t use_boot_reserve = 1;	/* cleared after early boot process */
133 uint_t can_steal_post_boot = 0;	/* set late in boot to enable stealing */
134 
135 /*
136  * enable_1gpg: controls 1g page support for user applications.
137  * By default, 1g pages are exported to user applications. enable_1gpg can
138  * be set to 0 to not export.
139  */
140 int	enable_1gpg = 1;
141 
142 /*
143  * AMD shanghai processors provide better management of 1gb ptes in its tlb.
144  * By default, 1g page support will be disabled for pre-shanghai AMD
145  * processors that don't have optimal tlb support for the 1g page size.
146  * chk_optimal_1gtlb can be set to 0 to force 1g page support on sub-optimal
147  * processors.
148  */
149 int	chk_optimal_1gtlb = 1;
150 
151 
152 #ifdef DEBUG
153 uint_t	map1gcnt;
154 #endif
155 
156 
157 /*
158  * A cpuset for all cpus. This is used for kernel address cross calls, since
159  * the kernel addresses apply to all cpus.
160  */
161 cpuset_t khat_cpuset;
162 
163 /*
164  * management stuff for hat structures
165  */
166 kmutex_t	hat_list_lock;
167 kcondvar_t	hat_list_cv;
168 kmem_cache_t	*hat_cache;
169 kmem_cache_t	*hat_hash_cache;
170 kmem_cache_t	*vlp_hash_cache;
171 
172 /*
173  * Simple statistics
174  */
175 struct hatstats hatstat;
176 
177 /*
178  * Some earlier hypervisor versions do not emulate cmpxchg of PTEs
179  * correctly.  For such hypervisors we must set PT_USER for kernel
180  * entries ourselves (normally the emulation would set PT_USER for
181  * kernel entries and PT_USER|PT_GLOBAL for user entries).  pt_kern is
182  * thus set appropriately.  Note that dboot/kbm is OK, as only the full
183  * HAT uses cmpxchg() and the other paths (hypercall etc.) were never
184  * incorrect.
185  */
186 int pt_kern;
187 
188 /*
189  * useful stuff for atomic access/clearing/setting REF/MOD/RO bits in page_t's.
190  */
191 extern void atomic_orb(uchar_t *addr, uchar_t val);
192 extern void atomic_andb(uchar_t *addr, uchar_t val);
193 
194 #ifndef __xpv
195 extern pfn_t memseg_get_start(struct memseg *);
196 #endif
197 
198 #define	PP_GETRM(pp, rmmask)    (pp->p_nrm & rmmask)
199 #define	PP_ISMOD(pp)		PP_GETRM(pp, P_MOD)
200 #define	PP_ISREF(pp)		PP_GETRM(pp, P_REF)
201 #define	PP_ISRO(pp)		PP_GETRM(pp, P_RO)
202 
203 #define	PP_SETRM(pp, rm)	atomic_orb(&(pp->p_nrm), rm)
204 #define	PP_SETMOD(pp)		PP_SETRM(pp, P_MOD)
205 #define	PP_SETREF(pp)		PP_SETRM(pp, P_REF)
206 #define	PP_SETRO(pp)		PP_SETRM(pp, P_RO)
207 
208 #define	PP_CLRRM(pp, rm)	atomic_andb(&(pp->p_nrm), ~(rm))
209 #define	PP_CLRMOD(pp)   	PP_CLRRM(pp, P_MOD)
210 #define	PP_CLRREF(pp)   	PP_CLRRM(pp, P_REF)
211 #define	PP_CLRRO(pp)    	PP_CLRRM(pp, P_RO)
212 #define	PP_CLRALL(pp)		PP_CLRRM(pp, P_MOD | P_REF | P_RO)
213 
214 /*
215  * kmem cache constructor for struct hat
216  */
217 /*ARGSUSED*/
218 static int
219 hati_constructor(void *buf, void *handle, int kmflags)
220 {
221 	hat_t	*hat = buf;
222 
223 	mutex_init(&hat->hat_mutex, NULL, MUTEX_DEFAULT, NULL);
224 	bzero(hat->hat_pages_mapped,
225 	    sizeof (pgcnt_t) * (mmu.max_page_level + 1));
226 	hat->hat_ism_pgcnt = 0;
227 	hat->hat_stats = 0;
228 	hat->hat_flags = 0;
229 	CPUSET_ZERO(hat->hat_cpus);
230 	hat->hat_htable = NULL;
231 	hat->hat_ht_hash = NULL;
232 	return (0);
233 }
234 
235 /*
236  * Allocate a hat structure for as. We also create the top level
237  * htable and initialize it to contain the kernel hat entries.
238  */
239 hat_t *
240 hat_alloc(struct as *as)
241 {
242 	hat_t			*hat;
243 	htable_t		*ht;	/* top level htable */
244 	uint_t			use_vlp;
245 	uint_t			r;
246 	hat_kernel_range_t	*rp;
247 	uintptr_t		va;
248 	uintptr_t		eva;
249 	uint_t			start;
250 	uint_t			cnt;
251 	htable_t		*src;
252 
253 	/*
254 	 * Once we start creating user process HATs we can enable
255 	 * the htable_steal() code.
256 	 */
257 	if (can_steal_post_boot == 0)
258 		can_steal_post_boot = 1;
259 
260 	ASSERT(AS_WRITE_HELD(as, &as->a_lock));
261 	hat = kmem_cache_alloc(hat_cache, KM_SLEEP);
262 	hat->hat_as = as;
263 	mutex_init(&hat->hat_mutex, NULL, MUTEX_DEFAULT, NULL);
264 	ASSERT(hat->hat_flags == 0);
265 
266 #if defined(__xpv)
267 	/*
268 	 * No VLP stuff on the hypervisor due to the 64-bit split top level
269 	 * page tables.  On 32-bit it's not needed as the hypervisor takes
270 	 * care of copying the top level PTEs to a below 4Gig page.
271 	 */
272 	use_vlp = 0;
273 #else	/* __xpv */
274 	/* 32 bit processes uses a VLP style hat when running with PAE */
275 #if defined(__amd64)
276 	use_vlp = (ttoproc(curthread)->p_model == DATAMODEL_ILP32);
277 #elif defined(__i386)
278 	use_vlp = mmu.pae_hat;
279 #endif
280 #endif	/* __xpv */
281 	if (use_vlp) {
282 		hat->hat_flags = HAT_VLP;
283 		bzero(hat->hat_vlp_ptes, VLP_SIZE);
284 	}
285 
286 	/*
287 	 * Allocate the htable hash
288 	 */
289 	if ((hat->hat_flags & HAT_VLP)) {
290 		hat->hat_num_hash = mmu.vlp_hash_cnt;
291 		hat->hat_ht_hash = kmem_cache_alloc(vlp_hash_cache, KM_SLEEP);
292 	} else {
293 		hat->hat_num_hash = mmu.hash_cnt;
294 		hat->hat_ht_hash = kmem_cache_alloc(hat_hash_cache, KM_SLEEP);
295 	}
296 	bzero(hat->hat_ht_hash, hat->hat_num_hash * sizeof (htable_t *));
297 
298 	/*
299 	 * Initialize Kernel HAT entries at the top of the top level page
300 	 * tables for the new hat.
301 	 */
302 	hat->hat_htable = NULL;
303 	hat->hat_ht_cached = NULL;
304 	XPV_DISALLOW_MIGRATE();
305 	ht = htable_create(hat, (uintptr_t)0, TOP_LEVEL(hat), NULL);
306 	hat->hat_htable = ht;
307 
308 #if defined(__amd64)
309 	if (hat->hat_flags & HAT_VLP)
310 		goto init_done;
311 #endif
312 
313 	for (r = 0; r < num_kernel_ranges; ++r) {
314 		rp = &kernel_ranges[r];
315 		for (va = rp->hkr_start_va; va != rp->hkr_end_va;
316 		    va += cnt * LEVEL_SIZE(rp->hkr_level)) {
317 
318 			if (rp->hkr_level == TOP_LEVEL(hat))
319 				ht = hat->hat_htable;
320 			else
321 				ht = htable_create(hat, va, rp->hkr_level,
322 				    NULL);
323 
324 			start = htable_va2entry(va, ht);
325 			cnt = HTABLE_NUM_PTES(ht) - start;
326 			eva = va +
327 			    ((uintptr_t)cnt << LEVEL_SHIFT(rp->hkr_level));
328 			if (rp->hkr_end_va != 0 &&
329 			    (eva > rp->hkr_end_va || eva == 0))
330 				cnt = htable_va2entry(rp->hkr_end_va, ht) -
331 				    start;
332 
333 #if defined(__i386) && !defined(__xpv)
334 			if (ht->ht_flags & HTABLE_VLP) {
335 				bcopy(&vlp_page[start],
336 				    &hat->hat_vlp_ptes[start],
337 				    cnt * sizeof (x86pte_t));
338 				continue;
339 			}
340 #endif
341 			src = htable_lookup(kas.a_hat, va, rp->hkr_level);
342 			ASSERT(src != NULL);
343 			x86pte_copy(src, ht, start, cnt);
344 			htable_release(src);
345 		}
346 	}
347 
348 init_done:
349 
350 #if defined(__xpv)
351 	/*
352 	 * Pin top level page tables after initializing them
353 	 */
354 	xen_pin(hat->hat_htable->ht_pfn, mmu.max_level);
355 #if defined(__amd64)
356 	xen_pin(hat->hat_user_ptable, mmu.max_level);
357 #endif
358 #endif
359 	XPV_ALLOW_MIGRATE();
360 
361 	/*
362 	 * Put it at the start of the global list of all hats (used by stealing)
363 	 *
364 	 * kas.a_hat is not in the list but is instead used to find the
365 	 * first and last items in the list.
366 	 *
367 	 * - kas.a_hat->hat_next points to the start of the user hats.
368 	 *   The list ends where hat->hat_next == NULL
369 	 *
370 	 * - kas.a_hat->hat_prev points to the last of the user hats.
371 	 *   The list begins where hat->hat_prev == NULL
372 	 */
373 	mutex_enter(&hat_list_lock);
374 	hat->hat_prev = NULL;
375 	hat->hat_next = kas.a_hat->hat_next;
376 	if (hat->hat_next)
377 		hat->hat_next->hat_prev = hat;
378 	else
379 		kas.a_hat->hat_prev = hat;
380 	kas.a_hat->hat_next = hat;
381 	mutex_exit(&hat_list_lock);
382 
383 	return (hat);
384 }
385 
386 /*
387  * process has finished executing but as has not been cleaned up yet.
388  */
389 /*ARGSUSED*/
390 void
391 hat_free_start(hat_t *hat)
392 {
393 	ASSERT(AS_WRITE_HELD(hat->hat_as, &hat->hat_as->a_lock));
394 
395 	/*
396 	 * If the hat is currently a stealing victim, wait for the stealing
397 	 * to finish.  Once we mark it as HAT_FREEING, htable_steal()
398 	 * won't look at its pagetables anymore.
399 	 */
400 	mutex_enter(&hat_list_lock);
401 	while (hat->hat_flags & HAT_VICTIM)
402 		cv_wait(&hat_list_cv, &hat_list_lock);
403 	hat->hat_flags |= HAT_FREEING;
404 	mutex_exit(&hat_list_lock);
405 }
406 
407 /*
408  * An address space is being destroyed, so we destroy the associated hat.
409  */
410 void
411 hat_free_end(hat_t *hat)
412 {
413 	kmem_cache_t *cache;
414 
415 	ASSERT(hat->hat_flags & HAT_FREEING);
416 
417 	/*
418 	 * must not be running on the given hat
419 	 */
420 	ASSERT(CPU->cpu_current_hat != hat);
421 
422 	/*
423 	 * Remove it from the list of HATs
424 	 */
425 	mutex_enter(&hat_list_lock);
426 	if (hat->hat_prev)
427 		hat->hat_prev->hat_next = hat->hat_next;
428 	else
429 		kas.a_hat->hat_next = hat->hat_next;
430 	if (hat->hat_next)
431 		hat->hat_next->hat_prev = hat->hat_prev;
432 	else
433 		kas.a_hat->hat_prev = hat->hat_prev;
434 	mutex_exit(&hat_list_lock);
435 	hat->hat_next = hat->hat_prev = NULL;
436 
437 #if defined(__xpv)
438 	/*
439 	 * On the hypervisor, unpin top level page table(s)
440 	 */
441 	xen_unpin(hat->hat_htable->ht_pfn);
442 #if defined(__amd64)
443 	xen_unpin(hat->hat_user_ptable);
444 #endif
445 #endif
446 
447 	/*
448 	 * Make a pass through the htables freeing them all up.
449 	 */
450 	htable_purge_hat(hat);
451 
452 	/*
453 	 * Decide which kmem cache the hash table came from, then free it.
454 	 */
455 	if (hat->hat_flags & HAT_VLP)
456 		cache = vlp_hash_cache;
457 	else
458 		cache = hat_hash_cache;
459 	kmem_cache_free(cache, hat->hat_ht_hash);
460 	hat->hat_ht_hash = NULL;
461 
462 	hat->hat_flags = 0;
463 	kmem_cache_free(hat_cache, hat);
464 }
465 
466 /*
467  * round kernelbase down to a supported value to use for _userlimit
468  *
469  * userlimit must be aligned down to an entry in the top level htable.
470  * The one exception is for 32 bit HAT's running PAE.
471  */
472 uintptr_t
473 hat_kernelbase(uintptr_t va)
474 {
475 #if defined(__i386)
476 	va &= LEVEL_MASK(1);
477 #endif
478 	if (IN_VA_HOLE(va))
479 		panic("_userlimit %p will fall in VA hole\n", (void *)va);
480 	return (va);
481 }
482 
483 /*
484  *
485  */
486 static void
487 set_max_page_level()
488 {
489 	level_t lvl;
490 
491 	if (!kbm_largepage_support) {
492 		lvl = 0;
493 	} else {
494 		if (is_x86_feature(x86_featureset, X86FSET_1GPG)) {
495 			lvl = 2;
496 			if (chk_optimal_1gtlb &&
497 			    cpuid_opteron_erratum(CPU, 6671130)) {
498 				lvl = 1;
499 			}
500 			if (plat_mnode_xcheck(LEVEL_SIZE(2) >>
501 			    LEVEL_SHIFT(0))) {
502 				lvl = 1;
503 			}
504 		} else {
505 			lvl = 1;
506 		}
507 	}
508 	mmu.max_page_level = lvl;
509 
510 	if ((lvl == 2) && (enable_1gpg == 0))
511 		mmu.umax_page_level = 1;
512 	else
513 		mmu.umax_page_level = lvl;
514 }
515 
516 /*
517  * Initialize hat data structures based on processor MMU information.
518  */
519 void
520 mmu_init(void)
521 {
522 	uint_t max_htables;
523 	uint_t pa_bits;
524 	uint_t va_bits;
525 	int i;
526 
527 	/*
528 	 * If CPU enabled the page table global bit, use it for the kernel
529 	 * This is bit 7 in CR4 (PGE - Page Global Enable).
530 	 */
531 	if (is_x86_feature(x86_featureset, X86FSET_PGE) &&
532 	    (getcr4() & CR4_PGE) != 0)
533 		mmu.pt_global = PT_GLOBAL;
534 
535 	/*
536 	 * Detect NX and PAE usage.
537 	 */
538 	mmu.pae_hat = kbm_pae_support;
539 	if (kbm_nx_support)
540 		mmu.pt_nx = PT_NX;
541 	else
542 		mmu.pt_nx = 0;
543 
544 	/*
545 	 * Use CPU info to set various MMU parameters
546 	 */
547 	cpuid_get_addrsize(CPU, &pa_bits, &va_bits);
548 
549 	if (va_bits < sizeof (void *) * NBBY) {
550 		mmu.hole_start = (1ul << (va_bits - 1));
551 		mmu.hole_end = 0ul - mmu.hole_start - 1;
552 	} else {
553 		mmu.hole_end = 0;
554 		mmu.hole_start = mmu.hole_end - 1;
555 	}
556 #if defined(OPTERON_ERRATUM_121)
557 	/*
558 	 * If erratum 121 has already been detected at this time, hole_start
559 	 * contains the value to be subtracted from mmu.hole_start.
560 	 */
561 	ASSERT(hole_start == 0 || opteron_erratum_121 != 0);
562 	hole_start = mmu.hole_start - hole_start;
563 #else
564 	hole_start = mmu.hole_start;
565 #endif
566 	hole_end = mmu.hole_end;
567 
568 	mmu.highest_pfn = mmu_btop((1ull << pa_bits) - 1);
569 	if (mmu.pae_hat == 0 && pa_bits > 32)
570 		mmu.highest_pfn = PFN_4G - 1;
571 
572 	if (mmu.pae_hat) {
573 		mmu.pte_size = 8;	/* 8 byte PTEs */
574 		mmu.pte_size_shift = 3;
575 	} else {
576 		mmu.pte_size = 4;	/* 4 byte PTEs */
577 		mmu.pte_size_shift = 2;
578 	}
579 
580 	if (mmu.pae_hat && !is_x86_feature(x86_featureset, X86FSET_PAE))
581 		panic("Processor does not support PAE");
582 
583 	if (!is_x86_feature(x86_featureset, X86FSET_CX8))
584 		panic("Processor does not support cmpxchg8b instruction");
585 
586 #if defined(__amd64)
587 
588 	mmu.num_level = 4;
589 	mmu.max_level = 3;
590 	mmu.ptes_per_table = 512;
591 	mmu.top_level_count = 512;
592 
593 	mmu.level_shift[0] = 12;
594 	mmu.level_shift[1] = 21;
595 	mmu.level_shift[2] = 30;
596 	mmu.level_shift[3] = 39;
597 
598 #elif defined(__i386)
599 
600 	if (mmu.pae_hat) {
601 		mmu.num_level = 3;
602 		mmu.max_level = 2;
603 		mmu.ptes_per_table = 512;
604 		mmu.top_level_count = 4;
605 
606 		mmu.level_shift[0] = 12;
607 		mmu.level_shift[1] = 21;
608 		mmu.level_shift[2] = 30;
609 
610 	} else {
611 		mmu.num_level = 2;
612 		mmu.max_level = 1;
613 		mmu.ptes_per_table = 1024;
614 		mmu.top_level_count = 1024;
615 
616 		mmu.level_shift[0] = 12;
617 		mmu.level_shift[1] = 22;
618 	}
619 
620 #endif	/* __i386 */
621 
622 	for (i = 0; i < mmu.num_level; ++i) {
623 		mmu.level_size[i] = 1UL << mmu.level_shift[i];
624 		mmu.level_offset[i] = mmu.level_size[i] - 1;
625 		mmu.level_mask[i] = ~mmu.level_offset[i];
626 	}
627 
628 	set_max_page_level();
629 
630 	mmu_page_sizes = mmu.max_page_level + 1;
631 	mmu_exported_page_sizes = mmu.umax_page_level + 1;
632 
633 	/* restrict legacy applications from using pagesizes 1g and above */
634 	mmu_legacy_page_sizes =
635 	    (mmu_exported_page_sizes > 2) ? 2 : mmu_exported_page_sizes;
636 
637 
638 	for (i = 0; i <= mmu.max_page_level; ++i) {
639 		mmu.pte_bits[i] = PT_VALID | pt_kern;
640 		if (i > 0)
641 			mmu.pte_bits[i] |= PT_PAGESIZE;
642 	}
643 
644 	/*
645 	 * NOTE Legacy 32 bit PAE mode only has the P_VALID bit at top level.
646 	 */
647 	for (i = 1; i < mmu.num_level; ++i)
648 		mmu.ptp_bits[i] = PT_PTPBITS;
649 
650 #if defined(__i386)
651 	mmu.ptp_bits[2] = PT_VALID;
652 #endif
653 
654 	/*
655 	 * Compute how many hash table entries to have per process for htables.
656 	 * We start with 1 page's worth of entries.
657 	 *
658 	 * If physical memory is small, reduce the amount need to cover it.
659 	 */
660 	max_htables = physmax / mmu.ptes_per_table;
661 	mmu.hash_cnt = MMU_PAGESIZE / sizeof (htable_t *);
662 	while (mmu.hash_cnt > 16 && mmu.hash_cnt >= max_htables)
663 		mmu.hash_cnt >>= 1;
664 	mmu.vlp_hash_cnt = mmu.hash_cnt;
665 
666 #if defined(__amd64)
667 	/*
668 	 * If running in 64 bits and physical memory is large,
669 	 * increase the size of the cache to cover all of memory for
670 	 * a 64 bit process.
671 	 */
672 #define	HASH_MAX_LENGTH 4
673 	while (mmu.hash_cnt * HASH_MAX_LENGTH < max_htables)
674 		mmu.hash_cnt <<= 1;
675 #endif
676 }
677 
678 
679 /*
680  * initialize hat data structures
681  */
682 void
683 hat_init()
684 {
685 #if defined(__i386)
686 	/*
687 	 * _userlimit must be aligned correctly
688 	 */
689 	if ((_userlimit & LEVEL_MASK(1)) != _userlimit) {
690 		prom_printf("hat_init(): _userlimit=%p, not aligned at %p\n",
691 		    (void *)_userlimit, (void *)LEVEL_SIZE(1));
692 		halt("hat_init(): Unable to continue");
693 	}
694 #endif
695 
696 	cv_init(&hat_list_cv, NULL, CV_DEFAULT, NULL);
697 
698 	/*
699 	 * initialize kmem caches
700 	 */
701 	htable_init();
702 	hment_init();
703 
704 	hat_cache = kmem_cache_create("hat_t",
705 	    sizeof (hat_t), 0, hati_constructor, NULL, NULL,
706 	    NULL, 0, 0);
707 
708 	hat_hash_cache = kmem_cache_create("HatHash",
709 	    mmu.hash_cnt * sizeof (htable_t *), 0, NULL, NULL, NULL,
710 	    NULL, 0, 0);
711 
712 	/*
713 	 * VLP hats can use a smaller hash table size on large memroy machines
714 	 */
715 	if (mmu.hash_cnt == mmu.vlp_hash_cnt) {
716 		vlp_hash_cache = hat_hash_cache;
717 	} else {
718 		vlp_hash_cache = kmem_cache_create("HatVlpHash",
719 		    mmu.vlp_hash_cnt * sizeof (htable_t *), 0, NULL, NULL, NULL,
720 		    NULL, 0, 0);
721 	}
722 
723 	/*
724 	 * Set up the kernel's hat
725 	 */
726 	AS_LOCK_ENTER(&kas, &kas.a_lock, RW_WRITER);
727 	kas.a_hat = kmem_cache_alloc(hat_cache, KM_NOSLEEP);
728 	mutex_init(&kas.a_hat->hat_mutex, NULL, MUTEX_DEFAULT, NULL);
729 	kas.a_hat->hat_as = &kas;
730 	kas.a_hat->hat_flags = 0;
731 	AS_LOCK_EXIT(&kas, &kas.a_lock);
732 
733 	CPUSET_ZERO(khat_cpuset);
734 	CPUSET_ADD(khat_cpuset, CPU->cpu_id);
735 
736 	/*
737 	 * The kernel hat's next pointer serves as the head of the hat list .
738 	 * The kernel hat's prev pointer tracks the last hat on the list for
739 	 * htable_steal() to use.
740 	 */
741 	kas.a_hat->hat_next = NULL;
742 	kas.a_hat->hat_prev = NULL;
743 
744 	/*
745 	 * Allocate an htable hash bucket for the kernel
746 	 * XX64 - tune for 64 bit procs
747 	 */
748 	kas.a_hat->hat_num_hash = mmu.hash_cnt;
749 	kas.a_hat->hat_ht_hash = kmem_cache_alloc(hat_hash_cache, KM_NOSLEEP);
750 	bzero(kas.a_hat->hat_ht_hash, mmu.hash_cnt * sizeof (htable_t *));
751 
752 	/*
753 	 * zero out the top level and cached htable pointers
754 	 */
755 	kas.a_hat->hat_ht_cached = NULL;
756 	kas.a_hat->hat_htable = NULL;
757 
758 	/*
759 	 * Pre-allocate hrm_hashtab before enabling the collection of
760 	 * refmod statistics.  Allocating on the fly would mean us
761 	 * running the risk of suffering recursive mutex enters or
762 	 * deadlocks.
763 	 */
764 	hrm_hashtab = kmem_zalloc(HRM_HASHSIZE * sizeof (struct hrmstat *),
765 	    KM_SLEEP);
766 }
767 
768 /*
769  * Prepare CPU specific pagetables for VLP processes on 64 bit kernels.
770  *
771  * Each CPU has a set of 2 pagetables that are reused for any 32 bit
772  * process it runs. They are the top level pagetable, hci_vlp_l3ptes, and
773  * the next to top level table for the bottom 512 Gig, hci_vlp_l2ptes.
774  */
775 /*ARGSUSED*/
776 static void
777 hat_vlp_setup(struct cpu *cpu)
778 {
779 #if defined(__amd64) && !defined(__xpv)
780 	struct hat_cpu_info *hci = cpu->cpu_hat_info;
781 	pfn_t pfn;
782 
783 	/*
784 	 * allocate the level==2 page table for the bottom most
785 	 * 512Gig of address space (this is where 32 bit apps live)
786 	 */
787 	ASSERT(hci != NULL);
788 	hci->hci_vlp_l2ptes = kmem_zalloc(MMU_PAGESIZE, KM_SLEEP);
789 
790 	/*
791 	 * Allocate a top level pagetable and copy the kernel's
792 	 * entries into it. Then link in hci_vlp_l2ptes in the 1st entry.
793 	 */
794 	hci->hci_vlp_l3ptes = kmem_zalloc(MMU_PAGESIZE, KM_SLEEP);
795 	hci->hci_vlp_pfn =
796 	    hat_getpfnum(kas.a_hat, (caddr_t)hci->hci_vlp_l3ptes);
797 	ASSERT(hci->hci_vlp_pfn != PFN_INVALID);
798 	bcopy(vlp_page, hci->hci_vlp_l3ptes, MMU_PAGESIZE);
799 
800 	pfn = hat_getpfnum(kas.a_hat, (caddr_t)hci->hci_vlp_l2ptes);
801 	ASSERT(pfn != PFN_INVALID);
802 	hci->hci_vlp_l3ptes[0] = MAKEPTP(pfn, 2);
803 #endif /* __amd64 && !__xpv */
804 }
805 
806 /*ARGSUSED*/
807 static void
808 hat_vlp_teardown(cpu_t *cpu)
809 {
810 #if defined(__amd64) && !defined(__xpv)
811 	struct hat_cpu_info *hci;
812 
813 	if ((hci = cpu->cpu_hat_info) == NULL)
814 		return;
815 	if (hci->hci_vlp_l2ptes)
816 		kmem_free(hci->hci_vlp_l2ptes, MMU_PAGESIZE);
817 	if (hci->hci_vlp_l3ptes)
818 		kmem_free(hci->hci_vlp_l3ptes, MMU_PAGESIZE);
819 #endif
820 }
821 
822 #define	NEXT_HKR(r, l, s, e) {			\
823 	kernel_ranges[r].hkr_level = l;		\
824 	kernel_ranges[r].hkr_start_va = s;	\
825 	kernel_ranges[r].hkr_end_va = e;	\
826 	++r;					\
827 }
828 
829 /*
830  * Finish filling in the kernel hat.
831  * Pre fill in all top level kernel page table entries for the kernel's
832  * part of the address range.  From this point on we can't use any new
833  * kernel large pages if they need PTE's at max_level
834  *
835  * create the kmap mappings.
836  */
837 void
838 hat_init_finish(void)
839 {
840 	size_t		size;
841 	uint_t		r = 0;
842 	uintptr_t	va;
843 	hat_kernel_range_t *rp;
844 
845 
846 	/*
847 	 * We are now effectively running on the kernel hat.
848 	 * Clearing use_boot_reserve shuts off using the pre-allocated boot
849 	 * reserve for all HAT allocations.  From here on, the reserves are
850 	 * only used when avoiding recursion in kmem_alloc().
851 	 */
852 	use_boot_reserve = 0;
853 	htable_adjust_reserve();
854 
855 	/*
856 	 * User HATs are initialized with copies of all kernel mappings in
857 	 * higher level page tables. Ensure that those entries exist.
858 	 */
859 #if defined(__amd64)
860 
861 	NEXT_HKR(r, 3, kernelbase, 0);
862 #if defined(__xpv)
863 	NEXT_HKR(r, 3, HYPERVISOR_VIRT_START, HYPERVISOR_VIRT_END);
864 #endif
865 
866 #elif defined(__i386)
867 
868 #if !defined(__xpv)
869 	if (mmu.pae_hat) {
870 		va = kernelbase;
871 		if ((va & LEVEL_MASK(2)) != va) {
872 			va = P2ROUNDUP(va, LEVEL_SIZE(2));
873 			NEXT_HKR(r, 1, kernelbase, va);
874 		}
875 		if (va != 0)
876 			NEXT_HKR(r, 2, va, 0);
877 	} else
878 #endif /* __xpv */
879 		NEXT_HKR(r, 1, kernelbase, 0);
880 
881 #endif /* __i386 */
882 
883 	num_kernel_ranges = r;
884 
885 	/*
886 	 * Create all the kernel pagetables that will have entries
887 	 * shared to user HATs.
888 	 */
889 	for (r = 0; r < num_kernel_ranges; ++r) {
890 		rp = &kernel_ranges[r];
891 		for (va = rp->hkr_start_va; va != rp->hkr_end_va;
892 		    va += LEVEL_SIZE(rp->hkr_level)) {
893 			htable_t *ht;
894 
895 			if (IN_HYPERVISOR_VA(va))
896 				continue;
897 
898 			/* can/must skip if a page mapping already exists */
899 			if (rp->hkr_level <= mmu.max_page_level &&
900 			    (ht = htable_getpage(kas.a_hat, va, NULL)) !=
901 			    NULL) {
902 				htable_release(ht);
903 				continue;
904 			}
905 
906 			(void) htable_create(kas.a_hat, va, rp->hkr_level - 1,
907 			    NULL);
908 		}
909 	}
910 
911 	/*
912 	 * 32 bit PAE metal kernels use only 4 of the 512 entries in the
913 	 * page holding the top level pagetable. We use the remainder for
914 	 * the "per CPU" page tables for VLP processes.
915 	 * Map the top level kernel pagetable into the kernel to make
916 	 * it easy to use bcopy access these tables.
917 	 */
918 	if (mmu.pae_hat) {
919 		vlp_page = vmem_alloc(heap_arena, MMU_PAGESIZE, VM_SLEEP);
920 		hat_devload(kas.a_hat, (caddr_t)vlp_page, MMU_PAGESIZE,
921 		    kas.a_hat->hat_htable->ht_pfn,
922 #if !defined(__xpv)
923 		    PROT_WRITE |
924 #endif
925 		    PROT_READ | HAT_NOSYNC | HAT_UNORDERED_OK,
926 		    HAT_LOAD | HAT_LOAD_NOCONSIST);
927 	}
928 	hat_vlp_setup(CPU);
929 
930 	/*
931 	 * Create kmap (cached mappings of kernel PTEs)
932 	 * for 32 bit we map from segmap_start .. ekernelheap
933 	 * for 64 bit we map from segmap_start .. segmap_start + segmapsize;
934 	 */
935 #if defined(__i386)
936 	size = (uintptr_t)ekernelheap - segmap_start;
937 #elif defined(__amd64)
938 	size = segmapsize;
939 #endif
940 	hat_kmap_init((uintptr_t)segmap_start, size);
941 }
942 
943 /*
944  * On 32 bit PAE mode, PTE's are 64 bits, but ordinary atomic memory references
945  * are 32 bit, so for safety we must use cas64() to install these.
946  */
947 #ifdef __i386
948 static void
949 reload_pae32(hat_t *hat, cpu_t *cpu)
950 {
951 	x86pte_t *src;
952 	x86pte_t *dest;
953 	x86pte_t pte;
954 	int i;
955 
956 	/*
957 	 * Load the 4 entries of the level 2 page table into this
958 	 * cpu's range of the vlp_page and point cr3 at them.
959 	 */
960 	ASSERT(mmu.pae_hat);
961 	src = hat->hat_vlp_ptes;
962 	dest = vlp_page + (cpu->cpu_id + 1) * VLP_NUM_PTES;
963 	for (i = 0; i < VLP_NUM_PTES; ++i) {
964 		for (;;) {
965 			pte = dest[i];
966 			if (pte == src[i])
967 				break;
968 			if (cas64(dest + i, pte, src[i]) != src[i])
969 				break;
970 		}
971 	}
972 }
973 #endif
974 
975 /*
976  * Switch to a new active hat, maintaining bit masks to track active CPUs.
977  *
978  * On the 32-bit PAE hypervisor, %cr3 is a 64-bit value, on metal it
979  * remains a 32-bit value.
980  */
981 void
982 hat_switch(hat_t *hat)
983 {
984 	uint64_t	newcr3;
985 	cpu_t		*cpu = CPU;
986 	hat_t		*old = cpu->cpu_current_hat;
987 
988 	/*
989 	 * set up this information first, so we don't miss any cross calls
990 	 */
991 	if (old != NULL) {
992 		if (old == hat)
993 			return;
994 		if (old != kas.a_hat)
995 			CPUSET_ATOMIC_DEL(old->hat_cpus, cpu->cpu_id);
996 	}
997 
998 	/*
999 	 * Add this CPU to the active set for this HAT.
1000 	 */
1001 	if (hat != kas.a_hat) {
1002 		CPUSET_ATOMIC_ADD(hat->hat_cpus, cpu->cpu_id);
1003 	}
1004 	cpu->cpu_current_hat = hat;
1005 
1006 	/*
1007 	 * now go ahead and load cr3
1008 	 */
1009 	if (hat->hat_flags & HAT_VLP) {
1010 #if defined(__amd64)
1011 		x86pte_t *vlpptep = cpu->cpu_hat_info->hci_vlp_l2ptes;
1012 
1013 		VLP_COPY(hat->hat_vlp_ptes, vlpptep);
1014 		newcr3 = MAKECR3(cpu->cpu_hat_info->hci_vlp_pfn);
1015 #elif defined(__i386)
1016 		reload_pae32(hat, cpu);
1017 		newcr3 = MAKECR3(kas.a_hat->hat_htable->ht_pfn) +
1018 		    (cpu->cpu_id + 1) * VLP_SIZE;
1019 #endif
1020 	} else {
1021 		newcr3 = MAKECR3((uint64_t)hat->hat_htable->ht_pfn);
1022 	}
1023 #ifdef __xpv
1024 	{
1025 		struct mmuext_op t[2];
1026 		uint_t retcnt;
1027 		uint_t opcnt = 1;
1028 
1029 		t[0].cmd = MMUEXT_NEW_BASEPTR;
1030 		t[0].arg1.mfn = mmu_btop(pa_to_ma(newcr3));
1031 #if defined(__amd64)
1032 		/*
1033 		 * There's an interesting problem here, as to what to
1034 		 * actually specify when switching to the kernel hat.
1035 		 * For now we'll reuse the kernel hat again.
1036 		 */
1037 		t[1].cmd = MMUEXT_NEW_USER_BASEPTR;
1038 		if (hat == kas.a_hat)
1039 			t[1].arg1.mfn = mmu_btop(pa_to_ma(newcr3));
1040 		else
1041 			t[1].arg1.mfn = pfn_to_mfn(hat->hat_user_ptable);
1042 		++opcnt;
1043 #endif	/* __amd64 */
1044 		if (HYPERVISOR_mmuext_op(t, opcnt, &retcnt, DOMID_SELF) < 0)
1045 			panic("HYPERVISOR_mmu_update() failed");
1046 		ASSERT(retcnt == opcnt);
1047 
1048 	}
1049 #else
1050 	setcr3(newcr3);
1051 #endif
1052 	ASSERT(cpu == CPU);
1053 }
1054 
1055 /*
1056  * Utility to return a valid x86pte_t from protections, pfn, and level number
1057  */
1058 static x86pte_t
1059 hati_mkpte(pfn_t pfn, uint_t attr, level_t level, uint_t flags)
1060 {
1061 	x86pte_t	pte;
1062 	uint_t		cache_attr = attr & HAT_ORDER_MASK;
1063 
1064 	pte = MAKEPTE(pfn, level);
1065 
1066 	if (attr & PROT_WRITE)
1067 		PTE_SET(pte, PT_WRITABLE);
1068 
1069 	if (attr & PROT_USER)
1070 		PTE_SET(pte, PT_USER);
1071 
1072 	if (!(attr & PROT_EXEC))
1073 		PTE_SET(pte, mmu.pt_nx);
1074 
1075 	/*
1076 	 * Set the software bits used track ref/mod sync's and hments.
1077 	 * If not using REF/MOD, set them to avoid h/w rewriting PTEs.
1078 	 */
1079 	if (flags & HAT_LOAD_NOCONSIST)
1080 		PTE_SET(pte, PT_NOCONSIST | PT_REF | PT_MOD);
1081 	else if (attr & HAT_NOSYNC)
1082 		PTE_SET(pte, PT_NOSYNC | PT_REF | PT_MOD);
1083 
1084 	/*
1085 	 * Set the caching attributes in the PTE. The combination
1086 	 * of attributes are poorly defined, so we pay attention
1087 	 * to them in the given order.
1088 	 *
1089 	 * The test for HAT_STRICTORDER is different because it's defined
1090 	 * as "0" - which was a stupid thing to do, but is too late to change!
1091 	 */
1092 	if (cache_attr == HAT_STRICTORDER) {
1093 		PTE_SET(pte, PT_NOCACHE);
1094 	/*LINTED [Lint hates empty ifs, but it's the obvious way to do this] */
1095 	} else if (cache_attr & (HAT_UNORDERED_OK | HAT_STORECACHING_OK)) {
1096 		/* nothing to set */;
1097 	} else if (cache_attr & (HAT_MERGING_OK | HAT_LOADCACHING_OK)) {
1098 		PTE_SET(pte, PT_NOCACHE);
1099 		if (is_x86_feature(x86_featureset, X86FSET_PAT))
1100 			PTE_SET(pte, (level == 0) ? PT_PAT_4K : PT_PAT_LARGE);
1101 		else
1102 			PTE_SET(pte, PT_WRITETHRU);
1103 	} else {
1104 		panic("hati_mkpte(): bad caching attributes: %x\n", cache_attr);
1105 	}
1106 
1107 	return (pte);
1108 }
1109 
1110 /*
1111  * Duplicate address translations of the parent to the child.
1112  * This function really isn't used anymore.
1113  */
1114 /*ARGSUSED*/
1115 int
1116 hat_dup(hat_t *old, hat_t *new, caddr_t addr, size_t len, uint_t flag)
1117 {
1118 	ASSERT((uintptr_t)addr < kernelbase);
1119 	ASSERT(new != kas.a_hat);
1120 	ASSERT(old != kas.a_hat);
1121 	return (0);
1122 }
1123 
1124 /*
1125  * Allocate any hat resources required for a process being swapped in.
1126  */
1127 /*ARGSUSED*/
1128 void
1129 hat_swapin(hat_t *hat)
1130 {
1131 	/* do nothing - we let everything fault back in */
1132 }
1133 
1134 /*
1135  * Unload all translations associated with an address space of a process
1136  * that is being swapped out.
1137  */
1138 void
1139 hat_swapout(hat_t *hat)
1140 {
1141 	uintptr_t	vaddr = (uintptr_t)0;
1142 	uintptr_t	eaddr = _userlimit;
1143 	htable_t	*ht = NULL;
1144 	level_t		l;
1145 
1146 	XPV_DISALLOW_MIGRATE();
1147 	/*
1148 	 * We can't just call hat_unload(hat, 0, _userlimit...)  here, because
1149 	 * seg_spt and shared pagetables can't be swapped out.
1150 	 * Take a look at segspt_shmswapout() - it's a big no-op.
1151 	 *
1152 	 * Instead we'll walk through all the address space and unload
1153 	 * any mappings which we are sure are not shared, not locked.
1154 	 */
1155 	ASSERT(IS_PAGEALIGNED(vaddr));
1156 	ASSERT(IS_PAGEALIGNED(eaddr));
1157 	ASSERT(AS_LOCK_HELD(hat->hat_as, &hat->hat_as->a_lock));
1158 	if ((uintptr_t)hat->hat_as->a_userlimit < eaddr)
1159 		eaddr = (uintptr_t)hat->hat_as->a_userlimit;
1160 
1161 	while (vaddr < eaddr) {
1162 		(void) htable_walk(hat, &ht, &vaddr, eaddr);
1163 		if (ht == NULL)
1164 			break;
1165 
1166 		ASSERT(!IN_VA_HOLE(vaddr));
1167 
1168 		/*
1169 		 * If the page table is shared skip its entire range.
1170 		 */
1171 		l = ht->ht_level;
1172 		if (ht->ht_flags & HTABLE_SHARED_PFN) {
1173 			vaddr = ht->ht_vaddr + LEVEL_SIZE(l + 1);
1174 			htable_release(ht);
1175 			ht = NULL;
1176 			continue;
1177 		}
1178 
1179 		/*
1180 		 * If the page table has no locked entries, unload this one.
1181 		 */
1182 		if (ht->ht_lock_cnt == 0)
1183 			hat_unload(hat, (caddr_t)vaddr, LEVEL_SIZE(l),
1184 			    HAT_UNLOAD_UNMAP);
1185 
1186 		/*
1187 		 * If we have a level 0 page table with locked entries,
1188 		 * skip the entire page table, otherwise skip just one entry.
1189 		 */
1190 		if (ht->ht_lock_cnt > 0 && l == 0)
1191 			vaddr = ht->ht_vaddr + LEVEL_SIZE(1);
1192 		else
1193 			vaddr += LEVEL_SIZE(l);
1194 	}
1195 	if (ht)
1196 		htable_release(ht);
1197 
1198 	/*
1199 	 * We're in swapout because the system is low on memory, so
1200 	 * go back and flush all the htables off the cached list.
1201 	 */
1202 	htable_purge_hat(hat);
1203 	XPV_ALLOW_MIGRATE();
1204 }
1205 
1206 /*
1207  * returns number of bytes that have valid mappings in hat.
1208  */
1209 size_t
1210 hat_get_mapped_size(hat_t *hat)
1211 {
1212 	size_t total = 0;
1213 	int l;
1214 
1215 	for (l = 0; l <= mmu.max_page_level; l++)
1216 		total += (hat->hat_pages_mapped[l] << LEVEL_SHIFT(l));
1217 	total += hat->hat_ism_pgcnt;
1218 
1219 	return (total);
1220 }
1221 
1222 /*
1223  * enable/disable collection of stats for hat.
1224  */
1225 int
1226 hat_stats_enable(hat_t *hat)
1227 {
1228 	atomic_add_32(&hat->hat_stats, 1);
1229 	return (1);
1230 }
1231 
1232 void
1233 hat_stats_disable(hat_t *hat)
1234 {
1235 	atomic_add_32(&hat->hat_stats, -1);
1236 }
1237 
1238 /*
1239  * Utility to sync the ref/mod bits from a page table entry to the page_t
1240  * We must be holding the mapping list lock when this is called.
1241  */
1242 static void
1243 hati_sync_pte_to_page(page_t *pp, x86pte_t pte, level_t level)
1244 {
1245 	uint_t	rm = 0;
1246 	pgcnt_t	pgcnt;
1247 
1248 	if (PTE_GET(pte, PT_SOFTWARE) >= PT_NOSYNC)
1249 		return;
1250 
1251 	if (PTE_GET(pte, PT_REF))
1252 		rm |= P_REF;
1253 
1254 	if (PTE_GET(pte, PT_MOD))
1255 		rm |= P_MOD;
1256 
1257 	if (rm == 0)
1258 		return;
1259 
1260 	/*
1261 	 * sync to all constituent pages of a large page
1262 	 */
1263 	ASSERT(x86_hm_held(pp));
1264 	pgcnt = page_get_pagecnt(level);
1265 	ASSERT(IS_P2ALIGNED(pp->p_pagenum, pgcnt));
1266 	for (; pgcnt > 0; --pgcnt) {
1267 		/*
1268 		 * hat_page_demote() can't decrease
1269 		 * pszc below this mapping size
1270 		 * since this large mapping existed after we
1271 		 * took mlist lock.
1272 		 */
1273 		ASSERT(pp->p_szc >= level);
1274 		hat_page_setattr(pp, rm);
1275 		++pp;
1276 	}
1277 }
1278 
1279 /*
1280  * This the set of PTE bits for PFN, permissions and caching
1281  * that are allowed to change on a HAT_LOAD_REMAP
1282  */
1283 #define	PT_REMAP_BITS							\
1284 	(PT_PADDR | PT_NX | PT_WRITABLE | PT_WRITETHRU |		\
1285 	PT_NOCACHE | PT_PAT_4K | PT_PAT_LARGE | PT_IGNORE | PT_REF | PT_MOD)
1286 
1287 #define	REMAPASSERT(EX)	if (!(EX)) panic("hati_pte_map: " #EX)
1288 /*
1289  * Do the low-level work to get a mapping entered into a HAT's pagetables
1290  * and in the mapping list of the associated page_t.
1291  */
1292 static int
1293 hati_pte_map(
1294 	htable_t	*ht,
1295 	uint_t		entry,
1296 	page_t		*pp,
1297 	x86pte_t	pte,
1298 	int		flags,
1299 	void		*pte_ptr)
1300 {
1301 	hat_t		*hat = ht->ht_hat;
1302 	x86pte_t	old_pte;
1303 	level_t		l = ht->ht_level;
1304 	hment_t		*hm;
1305 	uint_t		is_consist;
1306 	uint_t		is_locked;
1307 	int		rv = 0;
1308 
1309 	/*
1310 	 * Is this a consistent (ie. need mapping list lock) mapping?
1311 	 */
1312 	is_consist = (pp != NULL && (flags & HAT_LOAD_NOCONSIST) == 0);
1313 
1314 	/*
1315 	 * Track locked mapping count in the htable.  Do this first,
1316 	 * as we track locking even if there already is a mapping present.
1317 	 */
1318 	is_locked = (flags & HAT_LOAD_LOCK) != 0 && hat != kas.a_hat;
1319 	if (is_locked)
1320 		HTABLE_LOCK_INC(ht);
1321 
1322 	/*
1323 	 * Acquire the page's mapping list lock and get an hment to use.
1324 	 * Note that hment_prepare() might return NULL.
1325 	 */
1326 	if (is_consist) {
1327 		x86_hm_enter(pp);
1328 		hm = hment_prepare(ht, entry, pp);
1329 	}
1330 
1331 	/*
1332 	 * Set the new pte, retrieving the old one at the same time.
1333 	 */
1334 	old_pte = x86pte_set(ht, entry, pte, pte_ptr);
1335 
1336 	/*
1337 	 * Did we get a large page / page table collision?
1338 	 */
1339 	if (old_pte == LPAGE_ERROR) {
1340 		if (is_locked)
1341 			HTABLE_LOCK_DEC(ht);
1342 		rv = -1;
1343 		goto done;
1344 	}
1345 
1346 	/*
1347 	 * If the mapping didn't change there is nothing more to do.
1348 	 */
1349 	if (PTE_EQUIV(pte, old_pte))
1350 		goto done;
1351 
1352 	/*
1353 	 * Install a new mapping in the page's mapping list
1354 	 */
1355 	if (!PTE_ISVALID(old_pte)) {
1356 		if (is_consist) {
1357 			hment_assign(ht, entry, pp, hm);
1358 			x86_hm_exit(pp);
1359 		} else {
1360 			ASSERT(flags & HAT_LOAD_NOCONSIST);
1361 		}
1362 #if defined(__amd64)
1363 		if (ht->ht_flags & HTABLE_VLP) {
1364 			cpu_t *cpu = CPU;
1365 			x86pte_t *vlpptep = cpu->cpu_hat_info->hci_vlp_l2ptes;
1366 			VLP_COPY(hat->hat_vlp_ptes, vlpptep);
1367 		}
1368 #endif
1369 		HTABLE_INC(ht->ht_valid_cnt);
1370 		PGCNT_INC(hat, l);
1371 		return (rv);
1372 	}
1373 
1374 	/*
1375 	 * Remap's are more complicated:
1376 	 *  - HAT_LOAD_REMAP must be specified if changing the pfn.
1377 	 *    We also require that NOCONSIST be specified.
1378 	 *  - Otherwise only permission or caching bits may change.
1379 	 */
1380 	if (!PTE_ISPAGE(old_pte, l))
1381 		panic("non-null/page mapping pte=" FMT_PTE, old_pte);
1382 
1383 	if (PTE2PFN(old_pte, l) != PTE2PFN(pte, l)) {
1384 		REMAPASSERT(flags & HAT_LOAD_REMAP);
1385 		REMAPASSERT(flags & HAT_LOAD_NOCONSIST);
1386 		REMAPASSERT(PTE_GET(old_pte, PT_SOFTWARE) >= PT_NOCONSIST);
1387 		REMAPASSERT(pf_is_memory(PTE2PFN(old_pte, l)) ==
1388 		    pf_is_memory(PTE2PFN(pte, l)));
1389 		REMAPASSERT(!is_consist);
1390 	}
1391 
1392 	/*
1393 	 * We only let remaps change the certain bits in the PTE.
1394 	 */
1395 	if (PTE_GET(old_pte, ~PT_REMAP_BITS) != PTE_GET(pte, ~PT_REMAP_BITS))
1396 		panic("remap bits changed: old_pte="FMT_PTE", pte="FMT_PTE"\n",
1397 		    old_pte, pte);
1398 
1399 	/*
1400 	 * We don't create any mapping list entries on a remap, so release
1401 	 * any allocated hment after we drop the mapping list lock.
1402 	 */
1403 done:
1404 	if (is_consist) {
1405 		x86_hm_exit(pp);
1406 		if (hm != NULL)
1407 			hment_free(hm);
1408 	}
1409 	return (rv);
1410 }
1411 
1412 /*
1413  * Internal routine to load a single page table entry. This only fails if
1414  * we attempt to overwrite a page table link with a large page.
1415  */
1416 static int
1417 hati_load_common(
1418 	hat_t		*hat,
1419 	uintptr_t	va,
1420 	page_t		*pp,
1421 	uint_t		attr,
1422 	uint_t		flags,
1423 	level_t		level,
1424 	pfn_t		pfn)
1425 {
1426 	htable_t	*ht;
1427 	uint_t		entry;
1428 	x86pte_t	pte;
1429 	int		rv = 0;
1430 
1431 	/*
1432 	 * The number 16 is arbitrary and here to catch a recursion problem
1433 	 * early before we blow out the kernel stack.
1434 	 */
1435 	++curthread->t_hatdepth;
1436 	ASSERT(curthread->t_hatdepth < 16);
1437 
1438 	ASSERT(hat == kas.a_hat ||
1439 	    AS_LOCK_HELD(hat->hat_as, &hat->hat_as->a_lock));
1440 
1441 	if (flags & HAT_LOAD_SHARE)
1442 		hat->hat_flags |= HAT_SHARED;
1443 
1444 	/*
1445 	 * Find the page table that maps this page if it already exists.
1446 	 */
1447 	ht = htable_lookup(hat, va, level);
1448 
1449 	/*
1450 	 * We must have HAT_LOAD_NOCONSIST if page_t is NULL.
1451 	 */
1452 	if (pp == NULL)
1453 		flags |= HAT_LOAD_NOCONSIST;
1454 
1455 	if (ht == NULL) {
1456 		ht = htable_create(hat, va, level, NULL);
1457 		ASSERT(ht != NULL);
1458 	}
1459 	entry = htable_va2entry(va, ht);
1460 
1461 	/*
1462 	 * a bunch of paranoid error checking
1463 	 */
1464 	ASSERT(ht->ht_busy > 0);
1465 	if (ht->ht_vaddr > va || va > HTABLE_LAST_PAGE(ht))
1466 		panic("hati_load_common: bad htable %p, va %p",
1467 		    (void *)ht, (void *)va);
1468 	ASSERT(ht->ht_level == level);
1469 
1470 	/*
1471 	 * construct the new PTE
1472 	 */
1473 	if (hat == kas.a_hat)
1474 		attr &= ~PROT_USER;
1475 	pte = hati_mkpte(pfn, attr, level, flags);
1476 	if (hat == kas.a_hat && va >= kernelbase)
1477 		PTE_SET(pte, mmu.pt_global);
1478 
1479 	/*
1480 	 * establish the mapping
1481 	 */
1482 	rv = hati_pte_map(ht, entry, pp, pte, flags, NULL);
1483 
1484 	/*
1485 	 * release the htable and any reserves
1486 	 */
1487 	htable_release(ht);
1488 	--curthread->t_hatdepth;
1489 	return (rv);
1490 }
1491 
1492 /*
1493  * special case of hat_memload to deal with some kernel addrs for performance
1494  */
1495 static void
1496 hat_kmap_load(
1497 	caddr_t		addr,
1498 	page_t		*pp,
1499 	uint_t		attr,
1500 	uint_t		flags)
1501 {
1502 	uintptr_t	va = (uintptr_t)addr;
1503 	x86pte_t	pte;
1504 	pfn_t		pfn = page_pptonum(pp);
1505 	pgcnt_t		pg_off = mmu_btop(va - mmu.kmap_addr);
1506 	htable_t	*ht;
1507 	uint_t		entry;
1508 	void		*pte_ptr;
1509 
1510 	/*
1511 	 * construct the requested PTE
1512 	 */
1513 	attr &= ~PROT_USER;
1514 	attr |= HAT_STORECACHING_OK;
1515 	pte = hati_mkpte(pfn, attr, 0, flags);
1516 	PTE_SET(pte, mmu.pt_global);
1517 
1518 	/*
1519 	 * Figure out the pte_ptr and htable and use common code to finish up
1520 	 */
1521 	if (mmu.pae_hat)
1522 		pte_ptr = mmu.kmap_ptes + pg_off;
1523 	else
1524 		pte_ptr = (x86pte32_t *)mmu.kmap_ptes + pg_off;
1525 	ht = mmu.kmap_htables[(va - mmu.kmap_htables[0]->ht_vaddr) >>
1526 	    LEVEL_SHIFT(1)];
1527 	entry = htable_va2entry(va, ht);
1528 	++curthread->t_hatdepth;
1529 	ASSERT(curthread->t_hatdepth < 16);
1530 	(void) hati_pte_map(ht, entry, pp, pte, flags, pte_ptr);
1531 	--curthread->t_hatdepth;
1532 }
1533 
1534 /*
1535  * hat_memload() - load a translation to the given page struct
1536  *
1537  * Flags for hat_memload/hat_devload/hat_*attr.
1538  *
1539  * 	HAT_LOAD	Default flags to load a translation to the page.
1540  *
1541  * 	HAT_LOAD_LOCK	Lock down mapping resources; hat_map(), hat_memload(),
1542  *			and hat_devload().
1543  *
1544  *	HAT_LOAD_NOCONSIST Do not add mapping to page_t mapping list.
1545  *			sets PT_NOCONSIST
1546  *
1547  *	HAT_LOAD_SHARE	A flag to hat_memload() to indicate h/w page tables
1548  *			that map some user pages (not kas) is shared by more
1549  *			than one process (eg. ISM).
1550  *
1551  *	HAT_LOAD_REMAP	Reload a valid pte with a different page frame.
1552  *
1553  *	HAT_NO_KALLOC	Do not kmem_alloc while creating the mapping; at this
1554  *			point, it's setting up mapping to allocate internal
1555  *			hat layer data structures.  This flag forces hat layer
1556  *			to tap its reserves in order to prevent infinite
1557  *			recursion.
1558  *
1559  * The following is a protection attribute (like PROT_READ, etc.)
1560  *
1561  *	HAT_NOSYNC	set PT_NOSYNC - this mapping's ref/mod bits
1562  *			are never cleared.
1563  *
1564  * Installing new valid PTE's and creation of the mapping list
1565  * entry are controlled under the same lock. It's derived from the
1566  * page_t being mapped.
1567  */
1568 static uint_t supported_memload_flags =
1569 	HAT_LOAD | HAT_LOAD_LOCK | HAT_LOAD_ADV | HAT_LOAD_NOCONSIST |
1570 	HAT_LOAD_SHARE | HAT_NO_KALLOC | HAT_LOAD_REMAP | HAT_LOAD_TEXT;
1571 
1572 void
1573 hat_memload(
1574 	hat_t		*hat,
1575 	caddr_t		addr,
1576 	page_t		*pp,
1577 	uint_t		attr,
1578 	uint_t		flags)
1579 {
1580 	uintptr_t	va = (uintptr_t)addr;
1581 	level_t		level = 0;
1582 	pfn_t		pfn = page_pptonum(pp);
1583 
1584 	XPV_DISALLOW_MIGRATE();
1585 	ASSERT(IS_PAGEALIGNED(va));
1586 	ASSERT(hat == kas.a_hat || va < _userlimit);
1587 	ASSERT(hat == kas.a_hat ||
1588 	    AS_LOCK_HELD(hat->hat_as, &hat->hat_as->a_lock));
1589 	ASSERT((flags & supported_memload_flags) == flags);
1590 
1591 	ASSERT(!IN_VA_HOLE(va));
1592 	ASSERT(!PP_ISFREE(pp));
1593 
1594 	/*
1595 	 * kernel address special case for performance.
1596 	 */
1597 	if (mmu.kmap_addr <= va && va < mmu.kmap_eaddr) {
1598 		ASSERT(hat == kas.a_hat);
1599 		hat_kmap_load(addr, pp, attr, flags);
1600 		XPV_ALLOW_MIGRATE();
1601 		return;
1602 	}
1603 
1604 	/*
1605 	 * This is used for memory with normal caching enabled, so
1606 	 * always set HAT_STORECACHING_OK.
1607 	 */
1608 	attr |= HAT_STORECACHING_OK;
1609 	if (hati_load_common(hat, va, pp, attr, flags, level, pfn) != 0)
1610 		panic("unexpected hati_load_common() failure");
1611 	XPV_ALLOW_MIGRATE();
1612 }
1613 
1614 /* ARGSUSED */
1615 void
1616 hat_memload_region(struct hat *hat, caddr_t addr, struct page *pp,
1617     uint_t attr, uint_t flags, hat_region_cookie_t rcookie)
1618 {
1619 	hat_memload(hat, addr, pp, attr, flags);
1620 }
1621 
1622 /*
1623  * Load the given array of page structs using large pages when possible
1624  */
1625 void
1626 hat_memload_array(
1627 	hat_t		*hat,
1628 	caddr_t		addr,
1629 	size_t		len,
1630 	page_t		**pages,
1631 	uint_t		attr,
1632 	uint_t		flags)
1633 {
1634 	uintptr_t	va = (uintptr_t)addr;
1635 	uintptr_t	eaddr = va + len;
1636 	level_t		level;
1637 	size_t		pgsize;
1638 	pgcnt_t		pgindx = 0;
1639 	pfn_t		pfn;
1640 	pgcnt_t		i;
1641 
1642 	XPV_DISALLOW_MIGRATE();
1643 	ASSERT(IS_PAGEALIGNED(va));
1644 	ASSERT(hat == kas.a_hat || va + len <= _userlimit);
1645 	ASSERT(hat == kas.a_hat ||
1646 	    AS_LOCK_HELD(hat->hat_as, &hat->hat_as->a_lock));
1647 	ASSERT((flags & supported_memload_flags) == flags);
1648 
1649 	/*
1650 	 * memload is used for memory with full caching enabled, so
1651 	 * set HAT_STORECACHING_OK.
1652 	 */
1653 	attr |= HAT_STORECACHING_OK;
1654 
1655 	/*
1656 	 * handle all pages using largest possible pagesize
1657 	 */
1658 	while (va < eaddr) {
1659 		/*
1660 		 * decide what level mapping to use (ie. pagesize)
1661 		 */
1662 		pfn = page_pptonum(pages[pgindx]);
1663 		for (level = mmu.max_page_level; ; --level) {
1664 			pgsize = LEVEL_SIZE(level);
1665 			if (level == 0)
1666 				break;
1667 
1668 			if (!IS_P2ALIGNED(va, pgsize) ||
1669 			    (eaddr - va) < pgsize ||
1670 			    !IS_P2ALIGNED(pfn_to_pa(pfn), pgsize))
1671 				continue;
1672 
1673 			/*
1674 			 * To use a large mapping of this size, all the
1675 			 * pages we are passed must be sequential subpages
1676 			 * of the large page.
1677 			 * hat_page_demote() can't change p_szc because
1678 			 * all pages are locked.
1679 			 */
1680 			if (pages[pgindx]->p_szc >= level) {
1681 				for (i = 0; i < mmu_btop(pgsize); ++i) {
1682 					if (pfn + i !=
1683 					    page_pptonum(pages[pgindx + i]))
1684 						break;
1685 					ASSERT(pages[pgindx + i]->p_szc >=
1686 					    level);
1687 					ASSERT(pages[pgindx] + i ==
1688 					    pages[pgindx + i]);
1689 				}
1690 				if (i == mmu_btop(pgsize)) {
1691 #ifdef DEBUG
1692 					if (level == 2)
1693 						map1gcnt++;
1694 #endif
1695 					break;
1696 				}
1697 			}
1698 		}
1699 
1700 		/*
1701 		 * Load this page mapping. If the load fails, try a smaller
1702 		 * pagesize.
1703 		 */
1704 		ASSERT(!IN_VA_HOLE(va));
1705 		while (hati_load_common(hat, va, pages[pgindx], attr,
1706 		    flags, level, pfn) != 0) {
1707 			if (level == 0)
1708 				panic("unexpected hati_load_common() failure");
1709 			--level;
1710 			pgsize = LEVEL_SIZE(level);
1711 		}
1712 
1713 		/*
1714 		 * move to next page
1715 		 */
1716 		va += pgsize;
1717 		pgindx += mmu_btop(pgsize);
1718 	}
1719 	XPV_ALLOW_MIGRATE();
1720 }
1721 
1722 /* ARGSUSED */
1723 void
1724 hat_memload_array_region(struct hat *hat, caddr_t addr, size_t len,
1725     struct page **pps, uint_t attr, uint_t flags,
1726     hat_region_cookie_t rcookie)
1727 {
1728 	hat_memload_array(hat, addr, len, pps, attr, flags);
1729 }
1730 
1731 /*
1732  * void hat_devload(hat, addr, len, pf, attr, flags)
1733  *	load/lock the given page frame number
1734  *
1735  * Advisory ordering attributes. Apply only to device mappings.
1736  *
1737  * HAT_STRICTORDER: the CPU must issue the references in order, as the
1738  *	programmer specified.  This is the default.
1739  * HAT_UNORDERED_OK: the CPU may reorder the references (this is all kinds
1740  *	of reordering; store or load with store or load).
1741  * HAT_MERGING_OK: merging and batching: the CPU may merge individual stores
1742  *	to consecutive locations (for example, turn two consecutive byte
1743  *	stores into one halfword store), and it may batch individual loads
1744  *	(for example, turn two consecutive byte loads into one halfword load).
1745  *	This also implies re-ordering.
1746  * HAT_LOADCACHING_OK: the CPU may cache the data it fetches and reuse it
1747  *	until another store occurs.  The default is to fetch new data
1748  *	on every load.  This also implies merging.
1749  * HAT_STORECACHING_OK: the CPU may keep the data in the cache and push it to
1750  *	the device (perhaps with other data) at a later time.  The default is
1751  *	to push the data right away.  This also implies load caching.
1752  *
1753  * Equivalent of hat_memload(), but can be used for device memory where
1754  * there are no page_t's and we support additional flags (write merging, etc).
1755  * Note that we can have large page mappings with this interface.
1756  */
1757 int supported_devload_flags = HAT_LOAD | HAT_LOAD_LOCK |
1758 	HAT_LOAD_NOCONSIST | HAT_STRICTORDER | HAT_UNORDERED_OK |
1759 	HAT_MERGING_OK | HAT_LOADCACHING_OK | HAT_STORECACHING_OK;
1760 
1761 void
1762 hat_devload(
1763 	hat_t		*hat,
1764 	caddr_t		addr,
1765 	size_t		len,
1766 	pfn_t		pfn,
1767 	uint_t		attr,
1768 	int		flags)
1769 {
1770 	uintptr_t	va = ALIGN2PAGE(addr);
1771 	uintptr_t	eva = va + len;
1772 	level_t		level;
1773 	size_t		pgsize;
1774 	page_t		*pp;
1775 	int		f;	/* per PTE copy of flags  - maybe modified */
1776 	uint_t		a;	/* per PTE copy of attr */
1777 
1778 	XPV_DISALLOW_MIGRATE();
1779 	ASSERT(IS_PAGEALIGNED(va));
1780 	ASSERT(hat == kas.a_hat || eva <= _userlimit);
1781 	ASSERT(hat == kas.a_hat ||
1782 	    AS_LOCK_HELD(hat->hat_as, &hat->hat_as->a_lock));
1783 	ASSERT((flags & supported_devload_flags) == flags);
1784 
1785 	/*
1786 	 * handle all pages
1787 	 */
1788 	while (va < eva) {
1789 
1790 		/*
1791 		 * decide what level mapping to use (ie. pagesize)
1792 		 */
1793 		for (level = mmu.max_page_level; ; --level) {
1794 			pgsize = LEVEL_SIZE(level);
1795 			if (level == 0)
1796 				break;
1797 			if (IS_P2ALIGNED(va, pgsize) &&
1798 			    (eva - va) >= pgsize &&
1799 			    IS_P2ALIGNED(pfn, mmu_btop(pgsize))) {
1800 #ifdef DEBUG
1801 				if (level == 2)
1802 					map1gcnt++;
1803 #endif
1804 				break;
1805 			}
1806 		}
1807 
1808 		/*
1809 		 * If this is just memory then allow caching (this happens
1810 		 * for the nucleus pages) - though HAT_PLAT_NOCACHE can be used
1811 		 * to override that. If we don't have a page_t then make sure
1812 		 * NOCONSIST is set.
1813 		 */
1814 		a = attr;
1815 		f = flags;
1816 		if (!pf_is_memory(pfn))
1817 			f |= HAT_LOAD_NOCONSIST;
1818 		else if (!(a & HAT_PLAT_NOCACHE))
1819 			a |= HAT_STORECACHING_OK;
1820 
1821 		if (f & HAT_LOAD_NOCONSIST)
1822 			pp = NULL;
1823 		else
1824 			pp = page_numtopp_nolock(pfn);
1825 
1826 		/*
1827 		 * Check to make sure we are really trying to map a valid
1828 		 * memory page. The caller wishing to intentionally map
1829 		 * free memory pages will have passed the HAT_LOAD_NOCONSIST
1830 		 * flag, then pp will be NULL.
1831 		 */
1832 		if (pp != NULL) {
1833 			if (PP_ISFREE(pp)) {
1834 				panic("hat_devload: loading "
1835 				    "a mapping to free page %p", (void *)pp);
1836 			}
1837 
1838 			if (!PAGE_LOCKED(pp) && !PP_ISNORELOC(pp)) {
1839 				panic("hat_devload: loading a mapping "
1840 				    "to an unlocked page %p",
1841 				    (void *)pp);
1842 			}
1843 		}
1844 
1845 		/*
1846 		 * load this page mapping
1847 		 */
1848 		ASSERT(!IN_VA_HOLE(va));
1849 		while (hati_load_common(hat, va, pp, a, f, level, pfn) != 0) {
1850 			if (level == 0)
1851 				panic("unexpected hati_load_common() failure");
1852 			--level;
1853 			pgsize = LEVEL_SIZE(level);
1854 		}
1855 
1856 		/*
1857 		 * move to next page
1858 		 */
1859 		va += pgsize;
1860 		pfn += mmu_btop(pgsize);
1861 	}
1862 	XPV_ALLOW_MIGRATE();
1863 }
1864 
1865 /*
1866  * void hat_unlock(hat, addr, len)
1867  *	unlock the mappings to a given range of addresses
1868  *
1869  * Locks are tracked by ht_lock_cnt in the htable.
1870  */
1871 void
1872 hat_unlock(hat_t *hat, caddr_t addr, size_t len)
1873 {
1874 	uintptr_t	vaddr = (uintptr_t)addr;
1875 	uintptr_t	eaddr = vaddr + len;
1876 	htable_t	*ht = NULL;
1877 
1878 	/*
1879 	 * kernel entries are always locked, we don't track lock counts
1880 	 */
1881 	ASSERT(hat == kas.a_hat || eaddr <= _userlimit);
1882 	ASSERT(IS_PAGEALIGNED(vaddr));
1883 	ASSERT(IS_PAGEALIGNED(eaddr));
1884 	if (hat == kas.a_hat)
1885 		return;
1886 	if (eaddr > _userlimit)
1887 		panic("hat_unlock() address out of range - above _userlimit");
1888 
1889 	XPV_DISALLOW_MIGRATE();
1890 	ASSERT(AS_LOCK_HELD(hat->hat_as, &hat->hat_as->a_lock));
1891 	while (vaddr < eaddr) {
1892 		(void) htable_walk(hat, &ht, &vaddr, eaddr);
1893 		if (ht == NULL)
1894 			break;
1895 
1896 		ASSERT(!IN_VA_HOLE(vaddr));
1897 
1898 		if (ht->ht_lock_cnt < 1)
1899 			panic("hat_unlock(): lock_cnt < 1, "
1900 			    "htable=%p, vaddr=%p\n", (void *)ht, (void *)vaddr);
1901 		HTABLE_LOCK_DEC(ht);
1902 
1903 		vaddr += LEVEL_SIZE(ht->ht_level);
1904 	}
1905 	if (ht)
1906 		htable_release(ht);
1907 	XPV_ALLOW_MIGRATE();
1908 }
1909 
1910 /* ARGSUSED */
1911 void
1912 hat_unlock_region(struct hat *hat, caddr_t addr, size_t len,
1913     hat_region_cookie_t rcookie)
1914 {
1915 	panic("No shared region support on x86");
1916 }
1917 
1918 #if !defined(__xpv)
1919 /*
1920  * Cross call service routine to demap a virtual page on
1921  * the current CPU or flush all mappings in TLB.
1922  */
1923 /*ARGSUSED*/
1924 static int
1925 hati_demap_func(xc_arg_t a1, xc_arg_t a2, xc_arg_t a3)
1926 {
1927 	hat_t	*hat = (hat_t *)a1;
1928 	caddr_t	addr = (caddr_t)a2;
1929 
1930 	/*
1931 	 * If the target hat isn't the kernel and this CPU isn't operating
1932 	 * in the target hat, we can ignore the cross call.
1933 	 */
1934 	if (hat != kas.a_hat && hat != CPU->cpu_current_hat)
1935 		return (0);
1936 
1937 	/*
1938 	 * For a normal address, we just flush one page mapping
1939 	 */
1940 	if ((uintptr_t)addr != DEMAP_ALL_ADDR) {
1941 		mmu_tlbflush_entry(addr);
1942 		return (0);
1943 	}
1944 
1945 	/*
1946 	 * Otherwise we reload cr3 to effect a complete TLB flush.
1947 	 *
1948 	 * A reload of cr3 on a VLP process also means we must also recopy in
1949 	 * the pte values from the struct hat
1950 	 */
1951 	if (hat->hat_flags & HAT_VLP) {
1952 #if defined(__amd64)
1953 		x86pte_t *vlpptep = CPU->cpu_hat_info->hci_vlp_l2ptes;
1954 
1955 		VLP_COPY(hat->hat_vlp_ptes, vlpptep);
1956 #elif defined(__i386)
1957 		reload_pae32(hat, CPU);
1958 #endif
1959 	}
1960 	reload_cr3();
1961 	return (0);
1962 }
1963 
1964 /*
1965  * Flush all TLB entries, including global (ie. kernel) ones.
1966  */
1967 static void
1968 flush_all_tlb_entries(void)
1969 {
1970 	ulong_t cr4 = getcr4();
1971 
1972 	if (cr4 & CR4_PGE) {
1973 		setcr4(cr4 & ~(ulong_t)CR4_PGE);
1974 		setcr4(cr4);
1975 
1976 		/*
1977 		 * 32 bit PAE also needs to always reload_cr3()
1978 		 */
1979 		if (mmu.max_level == 2)
1980 			reload_cr3();
1981 	} else {
1982 		reload_cr3();
1983 	}
1984 }
1985 
1986 #define	TLB_CPU_HALTED	(01ul)
1987 #define	TLB_INVAL_ALL	(02ul)
1988 #define	CAS_TLB_INFO(cpu, old, new)	\
1989 	caslong((ulong_t *)&(cpu)->cpu_m.mcpu_tlb_info, (old), (new))
1990 
1991 /*
1992  * Record that a CPU is going idle
1993  */
1994 void
1995 tlb_going_idle(void)
1996 {
1997 	atomic_or_long((ulong_t *)&CPU->cpu_m.mcpu_tlb_info, TLB_CPU_HALTED);
1998 }
1999 
2000 /*
2001  * Service a delayed TLB flush if coming out of being idle.
2002  * It will be called from cpu idle notification with interrupt disabled.
2003  */
2004 void
2005 tlb_service(void)
2006 {
2007 	ulong_t tlb_info;
2008 	ulong_t found;
2009 
2010 	/*
2011 	 * We only have to do something if coming out of being idle.
2012 	 */
2013 	tlb_info = CPU->cpu_m.mcpu_tlb_info;
2014 	if (tlb_info & TLB_CPU_HALTED) {
2015 		ASSERT(CPU->cpu_current_hat == kas.a_hat);
2016 
2017 		/*
2018 		 * Atomic clear and fetch of old state.
2019 		 */
2020 		while ((found = CAS_TLB_INFO(CPU, tlb_info, 0)) != tlb_info) {
2021 			ASSERT(found & TLB_CPU_HALTED);
2022 			tlb_info = found;
2023 			SMT_PAUSE();
2024 		}
2025 		if (tlb_info & TLB_INVAL_ALL)
2026 			flush_all_tlb_entries();
2027 	}
2028 }
2029 #endif /* !__xpv */
2030 
2031 /*
2032  * Internal routine to do cross calls to invalidate a range of pages on
2033  * all CPUs using a given hat.
2034  */
2035 void
2036 hat_tlb_inval(hat_t *hat, uintptr_t va)
2037 {
2038 	extern int	flushes_require_xcalls;	/* from mp_startup.c */
2039 	cpuset_t	justme;
2040 	cpuset_t	cpus_to_shootdown;
2041 #ifndef __xpv
2042 	cpuset_t	check_cpus;
2043 	cpu_t		*cpup;
2044 	int		c;
2045 #endif
2046 
2047 	/*
2048 	 * If the hat is being destroyed, there are no more users, so
2049 	 * demap need not do anything.
2050 	 */
2051 	if (hat->hat_flags & HAT_FREEING)
2052 		return;
2053 
2054 	/*
2055 	 * If demapping from a shared pagetable, we best demap the
2056 	 * entire set of user TLBs, since we don't know what addresses
2057 	 * these were shared at.
2058 	 */
2059 	if (hat->hat_flags & HAT_SHARED) {
2060 		hat = kas.a_hat;
2061 		va = DEMAP_ALL_ADDR;
2062 	}
2063 
2064 	/*
2065 	 * if not running with multiple CPUs, don't use cross calls
2066 	 */
2067 	if (panicstr || !flushes_require_xcalls) {
2068 #ifdef __xpv
2069 		if (va == DEMAP_ALL_ADDR)
2070 			xen_flush_tlb();
2071 		else
2072 			xen_flush_va((caddr_t)va);
2073 #else
2074 		(void) hati_demap_func((xc_arg_t)hat, (xc_arg_t)va, NULL);
2075 #endif
2076 		return;
2077 	}
2078 
2079 
2080 	/*
2081 	 * Determine CPUs to shootdown. Kernel changes always do all CPUs.
2082 	 * Otherwise it's just CPUs currently executing in this hat.
2083 	 */
2084 	kpreempt_disable();
2085 	CPUSET_ONLY(justme, CPU->cpu_id);
2086 	if (hat == kas.a_hat)
2087 		cpus_to_shootdown = khat_cpuset;
2088 	else
2089 		cpus_to_shootdown = hat->hat_cpus;
2090 
2091 #ifndef __xpv
2092 	/*
2093 	 * If any CPUs in the set are idle, just request a delayed flush
2094 	 * and avoid waking them up.
2095 	 */
2096 	check_cpus = cpus_to_shootdown;
2097 	for (c = 0; c < NCPU && !CPUSET_ISNULL(check_cpus); ++c) {
2098 		ulong_t tlb_info;
2099 
2100 		if (!CPU_IN_SET(check_cpus, c))
2101 			continue;
2102 		CPUSET_DEL(check_cpus, c);
2103 		cpup = cpu[c];
2104 		if (cpup == NULL)
2105 			continue;
2106 
2107 		tlb_info = cpup->cpu_m.mcpu_tlb_info;
2108 		while (tlb_info == TLB_CPU_HALTED) {
2109 			(void) CAS_TLB_INFO(cpup, TLB_CPU_HALTED,
2110 			    TLB_CPU_HALTED | TLB_INVAL_ALL);
2111 			SMT_PAUSE();
2112 			tlb_info = cpup->cpu_m.mcpu_tlb_info;
2113 		}
2114 		if (tlb_info == (TLB_CPU_HALTED | TLB_INVAL_ALL)) {
2115 			HATSTAT_INC(hs_tlb_inval_delayed);
2116 			CPUSET_DEL(cpus_to_shootdown, c);
2117 		}
2118 	}
2119 #endif
2120 
2121 	if (CPUSET_ISNULL(cpus_to_shootdown) ||
2122 	    CPUSET_ISEQUAL(cpus_to_shootdown, justme)) {
2123 
2124 #ifdef __xpv
2125 		if (va == DEMAP_ALL_ADDR)
2126 			xen_flush_tlb();
2127 		else
2128 			xen_flush_va((caddr_t)va);
2129 #else
2130 		(void) hati_demap_func((xc_arg_t)hat, (xc_arg_t)va, NULL);
2131 #endif
2132 
2133 	} else {
2134 
2135 		CPUSET_ADD(cpus_to_shootdown, CPU->cpu_id);
2136 #ifdef __xpv
2137 		if (va == DEMAP_ALL_ADDR)
2138 			xen_gflush_tlb(cpus_to_shootdown);
2139 		else
2140 			xen_gflush_va((caddr_t)va, cpus_to_shootdown);
2141 #else
2142 		xc_call((xc_arg_t)hat, (xc_arg_t)va, NULL,
2143 		    CPUSET2BV(cpus_to_shootdown), hati_demap_func);
2144 #endif
2145 
2146 	}
2147 	kpreempt_enable();
2148 }
2149 
2150 /*
2151  * Interior routine for HAT_UNLOADs from hat_unload_callback(),
2152  * hat_kmap_unload() OR from hat_steal() code.  This routine doesn't
2153  * handle releasing of the htables.
2154  */
2155 void
2156 hat_pte_unmap(
2157 	htable_t	*ht,
2158 	uint_t		entry,
2159 	uint_t		flags,
2160 	x86pte_t	old_pte,
2161 	void		*pte_ptr)
2162 {
2163 	hat_t		*hat = ht->ht_hat;
2164 	hment_t		*hm = NULL;
2165 	page_t		*pp = NULL;
2166 	level_t		l = ht->ht_level;
2167 	pfn_t		pfn;
2168 
2169 	/*
2170 	 * We always track the locking counts, even if nothing is unmapped
2171 	 */
2172 	if ((flags & HAT_UNLOAD_UNLOCK) != 0 && hat != kas.a_hat) {
2173 		ASSERT(ht->ht_lock_cnt > 0);
2174 		HTABLE_LOCK_DEC(ht);
2175 	}
2176 
2177 	/*
2178 	 * Figure out which page's mapping list lock to acquire using the PFN
2179 	 * passed in "old" PTE. We then attempt to invalidate the PTE.
2180 	 * If another thread, probably a hat_pageunload, has asynchronously
2181 	 * unmapped/remapped this address we'll loop here.
2182 	 */
2183 	ASSERT(ht->ht_busy > 0);
2184 	while (PTE_ISVALID(old_pte)) {
2185 		pfn = PTE2PFN(old_pte, l);
2186 		if (PTE_GET(old_pte, PT_SOFTWARE) >= PT_NOCONSIST) {
2187 			pp = NULL;
2188 		} else {
2189 #ifdef __xpv
2190 			if (pfn == PFN_INVALID)
2191 				panic("Invalid PFN, but not PT_NOCONSIST");
2192 #endif
2193 			pp = page_numtopp_nolock(pfn);
2194 			if (pp == NULL) {
2195 				panic("no page_t, not NOCONSIST: old_pte="
2196 				    FMT_PTE " ht=%lx entry=0x%x pte_ptr=%lx",
2197 				    old_pte, (uintptr_t)ht, entry,
2198 				    (uintptr_t)pte_ptr);
2199 			}
2200 			x86_hm_enter(pp);
2201 		}
2202 
2203 		old_pte = x86pte_inval(ht, entry, old_pte, pte_ptr);
2204 
2205 		/*
2206 		 * If the page hadn't changed we've unmapped it and can proceed
2207 		 */
2208 		if (PTE_ISVALID(old_pte) && PTE2PFN(old_pte, l) == pfn)
2209 			break;
2210 
2211 		/*
2212 		 * Otherwise, we'll have to retry with the current old_pte.
2213 		 * Drop the hment lock, since the pfn may have changed.
2214 		 */
2215 		if (pp != NULL) {
2216 			x86_hm_exit(pp);
2217 			pp = NULL;
2218 		} else {
2219 			ASSERT(PTE_GET(old_pte, PT_SOFTWARE) >= PT_NOCONSIST);
2220 		}
2221 	}
2222 
2223 	/*
2224 	 * If the old mapping wasn't valid, there's nothing more to do
2225 	 */
2226 	if (!PTE_ISVALID(old_pte)) {
2227 		if (pp != NULL)
2228 			x86_hm_exit(pp);
2229 		return;
2230 	}
2231 
2232 	/*
2233 	 * Take care of syncing any MOD/REF bits and removing the hment.
2234 	 */
2235 	if (pp != NULL) {
2236 		if (!(flags & HAT_UNLOAD_NOSYNC))
2237 			hati_sync_pte_to_page(pp, old_pte, l);
2238 		hm = hment_remove(pp, ht, entry);
2239 		x86_hm_exit(pp);
2240 		if (hm != NULL)
2241 			hment_free(hm);
2242 	}
2243 
2244 	/*
2245 	 * Handle book keeping in the htable and hat
2246 	 */
2247 	ASSERT(ht->ht_valid_cnt > 0);
2248 	HTABLE_DEC(ht->ht_valid_cnt);
2249 	PGCNT_DEC(hat, l);
2250 }
2251 
2252 /*
2253  * very cheap unload implementation to special case some kernel addresses
2254  */
2255 static void
2256 hat_kmap_unload(caddr_t addr, size_t len, uint_t flags)
2257 {
2258 	uintptr_t	va = (uintptr_t)addr;
2259 	uintptr_t	eva = va + len;
2260 	pgcnt_t		pg_index;
2261 	htable_t	*ht;
2262 	uint_t		entry;
2263 	x86pte_t	*pte_ptr;
2264 	x86pte_t	old_pte;
2265 
2266 	for (; va < eva; va += MMU_PAGESIZE) {
2267 		/*
2268 		 * Get the PTE
2269 		 */
2270 		pg_index = mmu_btop(va - mmu.kmap_addr);
2271 		pte_ptr = PT_INDEX_PTR(mmu.kmap_ptes, pg_index);
2272 		old_pte = GET_PTE(pte_ptr);
2273 
2274 		/*
2275 		 * get the htable / entry
2276 		 */
2277 		ht = mmu.kmap_htables[(va - mmu.kmap_htables[0]->ht_vaddr)
2278 		    >> LEVEL_SHIFT(1)];
2279 		entry = htable_va2entry(va, ht);
2280 
2281 		/*
2282 		 * use mostly common code to unmap it.
2283 		 */
2284 		hat_pte_unmap(ht, entry, flags, old_pte, pte_ptr);
2285 	}
2286 }
2287 
2288 
2289 /*
2290  * unload a range of virtual address space (no callback)
2291  */
2292 void
2293 hat_unload(hat_t *hat, caddr_t addr, size_t len, uint_t flags)
2294 {
2295 	uintptr_t va = (uintptr_t)addr;
2296 
2297 	XPV_DISALLOW_MIGRATE();
2298 	ASSERT(hat == kas.a_hat || va + len <= _userlimit);
2299 
2300 	/*
2301 	 * special case for performance.
2302 	 */
2303 	if (mmu.kmap_addr <= va && va < mmu.kmap_eaddr) {
2304 		ASSERT(hat == kas.a_hat);
2305 		hat_kmap_unload(addr, len, flags);
2306 	} else {
2307 		hat_unload_callback(hat, addr, len, flags, NULL);
2308 	}
2309 	XPV_ALLOW_MIGRATE();
2310 }
2311 
2312 /*
2313  * Do the callbacks for ranges being unloaded.
2314  */
2315 typedef struct range_info {
2316 	uintptr_t	rng_va;
2317 	ulong_t		rng_cnt;
2318 	level_t		rng_level;
2319 } range_info_t;
2320 
2321 static void
2322 handle_ranges(hat_callback_t *cb, uint_t cnt, range_info_t *range)
2323 {
2324 	/*
2325 	 * do callbacks to upper level VM system
2326 	 */
2327 	while (cb != NULL && cnt > 0) {
2328 		--cnt;
2329 		cb->hcb_start_addr = (caddr_t)range[cnt].rng_va;
2330 		cb->hcb_end_addr = cb->hcb_start_addr;
2331 		cb->hcb_end_addr +=
2332 		    range[cnt].rng_cnt << LEVEL_SIZE(range[cnt].rng_level);
2333 		cb->hcb_function(cb);
2334 	}
2335 }
2336 
2337 /*
2338  * Unload a given range of addresses (has optional callback)
2339  *
2340  * Flags:
2341  * define	HAT_UNLOAD		0x00
2342  * define	HAT_UNLOAD_NOSYNC	0x02
2343  * define	HAT_UNLOAD_UNLOCK	0x04
2344  * define	HAT_UNLOAD_OTHER	0x08 - not used
2345  * define	HAT_UNLOAD_UNMAP	0x10 - same as HAT_UNLOAD
2346  */
2347 #define	MAX_UNLOAD_CNT (8)
2348 void
2349 hat_unload_callback(
2350 	hat_t		*hat,
2351 	caddr_t		addr,
2352 	size_t		len,
2353 	uint_t		flags,
2354 	hat_callback_t	*cb)
2355 {
2356 	uintptr_t	vaddr = (uintptr_t)addr;
2357 	uintptr_t	eaddr = vaddr + len;
2358 	htable_t	*ht = NULL;
2359 	uint_t		entry;
2360 	uintptr_t	contig_va = (uintptr_t)-1L;
2361 	range_info_t	r[MAX_UNLOAD_CNT];
2362 	uint_t		r_cnt = 0;
2363 	x86pte_t	old_pte;
2364 
2365 	XPV_DISALLOW_MIGRATE();
2366 	ASSERT(hat == kas.a_hat || eaddr <= _userlimit);
2367 	ASSERT(IS_PAGEALIGNED(vaddr));
2368 	ASSERT(IS_PAGEALIGNED(eaddr));
2369 
2370 	/*
2371 	 * Special case a single page being unloaded for speed. This happens
2372 	 * quite frequently, COW faults after a fork() for example.
2373 	 */
2374 	if (cb == NULL && len == MMU_PAGESIZE) {
2375 		ht = htable_getpte(hat, vaddr, &entry, &old_pte, 0);
2376 		if (ht != NULL) {
2377 			if (PTE_ISVALID(old_pte))
2378 				hat_pte_unmap(ht, entry, flags, old_pte, NULL);
2379 			htable_release(ht);
2380 		}
2381 		XPV_ALLOW_MIGRATE();
2382 		return;
2383 	}
2384 
2385 	while (vaddr < eaddr) {
2386 		old_pte = htable_walk(hat, &ht, &vaddr, eaddr);
2387 		if (ht == NULL)
2388 			break;
2389 
2390 		ASSERT(!IN_VA_HOLE(vaddr));
2391 
2392 		if (vaddr < (uintptr_t)addr)
2393 			panic("hat_unload_callback(): unmap inside large page");
2394 
2395 		/*
2396 		 * We'll do the call backs for contiguous ranges
2397 		 */
2398 		if (vaddr != contig_va ||
2399 		    (r_cnt > 0 && r[r_cnt - 1].rng_level != ht->ht_level)) {
2400 			if (r_cnt == MAX_UNLOAD_CNT) {
2401 				handle_ranges(cb, r_cnt, r);
2402 				r_cnt = 0;
2403 			}
2404 			r[r_cnt].rng_va = vaddr;
2405 			r[r_cnt].rng_cnt = 0;
2406 			r[r_cnt].rng_level = ht->ht_level;
2407 			++r_cnt;
2408 		}
2409 
2410 		/*
2411 		 * Unload one mapping from the page tables.
2412 		 */
2413 		entry = htable_va2entry(vaddr, ht);
2414 		hat_pte_unmap(ht, entry, flags, old_pte, NULL);
2415 		ASSERT(ht->ht_level <= mmu.max_page_level);
2416 		vaddr += LEVEL_SIZE(ht->ht_level);
2417 		contig_va = vaddr;
2418 		++r[r_cnt - 1].rng_cnt;
2419 	}
2420 	if (ht)
2421 		htable_release(ht);
2422 
2423 	/*
2424 	 * handle last range for callbacks
2425 	 */
2426 	if (r_cnt > 0)
2427 		handle_ranges(cb, r_cnt, r);
2428 	XPV_ALLOW_MIGRATE();
2429 }
2430 
2431 /*
2432  * Invalidate a virtual address translation on a slave CPU during
2433  * panic() dumps.
2434  */
2435 void
2436 hat_flush_range(hat_t *hat, caddr_t va, size_t size)
2437 {
2438 	ssize_t sz;
2439 	caddr_t endva = va + size;
2440 
2441 	while (va < endva) {
2442 		sz = hat_getpagesize(hat, va);
2443 		if (sz < 0) {
2444 #ifdef __xpv
2445 			xen_flush_tlb();
2446 #else
2447 			flush_all_tlb_entries();
2448 #endif
2449 			break;
2450 		}
2451 #ifdef __xpv
2452 		xen_flush_va(va);
2453 #else
2454 		mmu_tlbflush_entry(va);
2455 #endif
2456 		va += sz;
2457 	}
2458 }
2459 
2460 /*
2461  * synchronize mapping with software data structures
2462  *
2463  * This interface is currently only used by the working set monitor
2464  * driver.
2465  */
2466 /*ARGSUSED*/
2467 void
2468 hat_sync(hat_t *hat, caddr_t addr, size_t len, uint_t flags)
2469 {
2470 	uintptr_t	vaddr = (uintptr_t)addr;
2471 	uintptr_t	eaddr = vaddr + len;
2472 	htable_t	*ht = NULL;
2473 	uint_t		entry;
2474 	x86pte_t	pte;
2475 	x86pte_t	save_pte;
2476 	x86pte_t	new;
2477 	page_t		*pp;
2478 
2479 	ASSERT(!IN_VA_HOLE(vaddr));
2480 	ASSERT(IS_PAGEALIGNED(vaddr));
2481 	ASSERT(IS_PAGEALIGNED(eaddr));
2482 	ASSERT(hat == kas.a_hat || eaddr <= _userlimit);
2483 
2484 	XPV_DISALLOW_MIGRATE();
2485 	for (; vaddr < eaddr; vaddr += LEVEL_SIZE(ht->ht_level)) {
2486 try_again:
2487 		pte = htable_walk(hat, &ht, &vaddr, eaddr);
2488 		if (ht == NULL)
2489 			break;
2490 		entry = htable_va2entry(vaddr, ht);
2491 
2492 		if (PTE_GET(pte, PT_SOFTWARE) >= PT_NOSYNC ||
2493 		    PTE_GET(pte, PT_REF | PT_MOD) == 0)
2494 			continue;
2495 
2496 		/*
2497 		 * We need to acquire the mapping list lock to protect
2498 		 * against hat_pageunload(), hat_unload(), etc.
2499 		 */
2500 		pp = page_numtopp_nolock(PTE2PFN(pte, ht->ht_level));
2501 		if (pp == NULL)
2502 			break;
2503 		x86_hm_enter(pp);
2504 		save_pte = pte;
2505 		pte = x86pte_get(ht, entry);
2506 		if (pte != save_pte) {
2507 			x86_hm_exit(pp);
2508 			goto try_again;
2509 		}
2510 		if (PTE_GET(pte, PT_SOFTWARE) >= PT_NOSYNC ||
2511 		    PTE_GET(pte, PT_REF | PT_MOD) == 0) {
2512 			x86_hm_exit(pp);
2513 			continue;
2514 		}
2515 
2516 		/*
2517 		 * Need to clear ref or mod bits. We may compete with
2518 		 * hardware updating the R/M bits and have to try again.
2519 		 */
2520 		if (flags == HAT_SYNC_ZERORM) {
2521 			new = pte;
2522 			PTE_CLR(new, PT_REF | PT_MOD);
2523 			pte = hati_update_pte(ht, entry, pte, new);
2524 			if (pte != 0) {
2525 				x86_hm_exit(pp);
2526 				goto try_again;
2527 			}
2528 		} else {
2529 			/*
2530 			 * sync the PTE to the page_t
2531 			 */
2532 			hati_sync_pte_to_page(pp, save_pte, ht->ht_level);
2533 		}
2534 		x86_hm_exit(pp);
2535 	}
2536 	if (ht)
2537 		htable_release(ht);
2538 	XPV_ALLOW_MIGRATE();
2539 }
2540 
2541 /*
2542  * void	hat_map(hat, addr, len, flags)
2543  */
2544 /*ARGSUSED*/
2545 void
2546 hat_map(hat_t *hat, caddr_t addr, size_t len, uint_t flags)
2547 {
2548 	/* does nothing */
2549 }
2550 
2551 /*
2552  * uint_t hat_getattr(hat, addr, *attr)
2553  *	returns attr for <hat,addr> in *attr.  returns 0 if there was a
2554  *	mapping and *attr is valid, nonzero if there was no mapping and
2555  *	*attr is not valid.
2556  */
2557 uint_t
2558 hat_getattr(hat_t *hat, caddr_t addr, uint_t *attr)
2559 {
2560 	uintptr_t	vaddr = ALIGN2PAGE(addr);
2561 	htable_t	*ht = NULL;
2562 	x86pte_t	pte;
2563 
2564 	ASSERT(hat == kas.a_hat || vaddr <= _userlimit);
2565 
2566 	if (IN_VA_HOLE(vaddr))
2567 		return ((uint_t)-1);
2568 
2569 	ht = htable_getpte(hat, vaddr, NULL, &pte, mmu.max_page_level);
2570 	if (ht == NULL)
2571 		return ((uint_t)-1);
2572 
2573 	if (!PTE_ISVALID(pte) || !PTE_ISPAGE(pte, ht->ht_level)) {
2574 		htable_release(ht);
2575 		return ((uint_t)-1);
2576 	}
2577 
2578 	*attr = PROT_READ;
2579 	if (PTE_GET(pte, PT_WRITABLE))
2580 		*attr |= PROT_WRITE;
2581 	if (PTE_GET(pte, PT_USER))
2582 		*attr |= PROT_USER;
2583 	if (!PTE_GET(pte, mmu.pt_nx))
2584 		*attr |= PROT_EXEC;
2585 	if (PTE_GET(pte, PT_SOFTWARE) >= PT_NOSYNC)
2586 		*attr |= HAT_NOSYNC;
2587 	htable_release(ht);
2588 	return (0);
2589 }
2590 
2591 /*
2592  * hat_updateattr() applies the given attribute change to an existing mapping
2593  */
2594 #define	HAT_LOAD_ATTR		1
2595 #define	HAT_SET_ATTR		2
2596 #define	HAT_CLR_ATTR		3
2597 
2598 static void
2599 hat_updateattr(hat_t *hat, caddr_t addr, size_t len, uint_t attr, int what)
2600 {
2601 	uintptr_t	vaddr = (uintptr_t)addr;
2602 	uintptr_t	eaddr = (uintptr_t)addr + len;
2603 	htable_t	*ht = NULL;
2604 	uint_t		entry;
2605 	x86pte_t	oldpte, newpte;
2606 	page_t		*pp;
2607 
2608 	XPV_DISALLOW_MIGRATE();
2609 	ASSERT(IS_PAGEALIGNED(vaddr));
2610 	ASSERT(IS_PAGEALIGNED(eaddr));
2611 	ASSERT(hat == kas.a_hat ||
2612 	    AS_LOCK_HELD(hat->hat_as, &hat->hat_as->a_lock));
2613 	for (; vaddr < eaddr; vaddr += LEVEL_SIZE(ht->ht_level)) {
2614 try_again:
2615 		oldpte = htable_walk(hat, &ht, &vaddr, eaddr);
2616 		if (ht == NULL)
2617 			break;
2618 		if (PTE_GET(oldpte, PT_SOFTWARE) >= PT_NOCONSIST)
2619 			continue;
2620 
2621 		pp = page_numtopp_nolock(PTE2PFN(oldpte, ht->ht_level));
2622 		if (pp == NULL)
2623 			continue;
2624 		x86_hm_enter(pp);
2625 
2626 		newpte = oldpte;
2627 		/*
2628 		 * We found a page table entry in the desired range,
2629 		 * figure out the new attributes.
2630 		 */
2631 		if (what == HAT_SET_ATTR || what == HAT_LOAD_ATTR) {
2632 			if ((attr & PROT_WRITE) &&
2633 			    !PTE_GET(oldpte, PT_WRITABLE))
2634 				newpte |= PT_WRITABLE;
2635 
2636 			if ((attr & HAT_NOSYNC) &&
2637 			    PTE_GET(oldpte, PT_SOFTWARE) < PT_NOSYNC)
2638 				newpte |= PT_NOSYNC;
2639 
2640 			if ((attr & PROT_EXEC) && PTE_GET(oldpte, mmu.pt_nx))
2641 				newpte &= ~mmu.pt_nx;
2642 		}
2643 
2644 		if (what == HAT_LOAD_ATTR) {
2645 			if (!(attr & PROT_WRITE) &&
2646 			    PTE_GET(oldpte, PT_WRITABLE))
2647 				newpte &= ~PT_WRITABLE;
2648 
2649 			if (!(attr & HAT_NOSYNC) &&
2650 			    PTE_GET(oldpte, PT_SOFTWARE) >= PT_NOSYNC)
2651 				newpte &= ~PT_SOFTWARE;
2652 
2653 			if (!(attr & PROT_EXEC) && !PTE_GET(oldpte, mmu.pt_nx))
2654 				newpte |= mmu.pt_nx;
2655 		}
2656 
2657 		if (what == HAT_CLR_ATTR) {
2658 			if ((attr & PROT_WRITE) && PTE_GET(oldpte, PT_WRITABLE))
2659 				newpte &= ~PT_WRITABLE;
2660 
2661 			if ((attr & HAT_NOSYNC) &&
2662 			    PTE_GET(oldpte, PT_SOFTWARE) >= PT_NOSYNC)
2663 				newpte &= ~PT_SOFTWARE;
2664 
2665 			if ((attr & PROT_EXEC) && !PTE_GET(oldpte, mmu.pt_nx))
2666 				newpte |= mmu.pt_nx;
2667 		}
2668 
2669 		/*
2670 		 * Ensure NOSYNC/NOCONSIST mappings have REF and MOD set.
2671 		 * x86pte_set() depends on this.
2672 		 */
2673 		if (PTE_GET(newpte, PT_SOFTWARE) >= PT_NOSYNC)
2674 			newpte |= PT_REF | PT_MOD;
2675 
2676 		/*
2677 		 * what about PROT_READ or others? this code only handles:
2678 		 * EXEC, WRITE, NOSYNC
2679 		 */
2680 
2681 		/*
2682 		 * If new PTE really changed, update the table.
2683 		 */
2684 		if (newpte != oldpte) {
2685 			entry = htable_va2entry(vaddr, ht);
2686 			oldpte = hati_update_pte(ht, entry, oldpte, newpte);
2687 			if (oldpte != 0) {
2688 				x86_hm_exit(pp);
2689 				goto try_again;
2690 			}
2691 		}
2692 		x86_hm_exit(pp);
2693 	}
2694 	if (ht)
2695 		htable_release(ht);
2696 	XPV_ALLOW_MIGRATE();
2697 }
2698 
2699 /*
2700  * Various wrappers for hat_updateattr()
2701  */
2702 void
2703 hat_setattr(hat_t *hat, caddr_t addr, size_t len, uint_t attr)
2704 {
2705 	ASSERT(hat == kas.a_hat || (uintptr_t)addr + len <= _userlimit);
2706 	hat_updateattr(hat, addr, len, attr, HAT_SET_ATTR);
2707 }
2708 
2709 void
2710 hat_clrattr(hat_t *hat, caddr_t addr, size_t len, uint_t attr)
2711 {
2712 	ASSERT(hat == kas.a_hat || (uintptr_t)addr + len <= _userlimit);
2713 	hat_updateattr(hat, addr, len, attr, HAT_CLR_ATTR);
2714 }
2715 
2716 void
2717 hat_chgattr(hat_t *hat, caddr_t addr, size_t len, uint_t attr)
2718 {
2719 	ASSERT(hat == kas.a_hat || (uintptr_t)addr + len <= _userlimit);
2720 	hat_updateattr(hat, addr, len, attr, HAT_LOAD_ATTR);
2721 }
2722 
2723 void
2724 hat_chgprot(hat_t *hat, caddr_t addr, size_t len, uint_t vprot)
2725 {
2726 	ASSERT(hat == kas.a_hat || (uintptr_t)addr + len <= _userlimit);
2727 	hat_updateattr(hat, addr, len, vprot & HAT_PROT_MASK, HAT_LOAD_ATTR);
2728 }
2729 
2730 /*
2731  * size_t hat_getpagesize(hat, addr)
2732  *	returns pagesize in bytes for <hat, addr>. returns -1 of there is
2733  *	no mapping. This is an advisory call.
2734  */
2735 ssize_t
2736 hat_getpagesize(hat_t *hat, caddr_t addr)
2737 {
2738 	uintptr_t	vaddr = ALIGN2PAGE(addr);
2739 	htable_t	*ht;
2740 	size_t		pagesize;
2741 
2742 	ASSERT(hat == kas.a_hat || vaddr <= _userlimit);
2743 	if (IN_VA_HOLE(vaddr))
2744 		return (-1);
2745 	ht = htable_getpage(hat, vaddr, NULL);
2746 	if (ht == NULL)
2747 		return (-1);
2748 	pagesize = LEVEL_SIZE(ht->ht_level);
2749 	htable_release(ht);
2750 	return (pagesize);
2751 }
2752 
2753 
2754 
2755 /*
2756  * pfn_t hat_getpfnum(hat, addr)
2757  *	returns pfn for <hat, addr> or PFN_INVALID if mapping is invalid.
2758  */
2759 pfn_t
2760 hat_getpfnum(hat_t *hat, caddr_t addr)
2761 {
2762 	uintptr_t	vaddr = ALIGN2PAGE(addr);
2763 	htable_t	*ht;
2764 	uint_t		entry;
2765 	pfn_t		pfn = PFN_INVALID;
2766 
2767 	ASSERT(hat == kas.a_hat || vaddr <= _userlimit);
2768 	if (khat_running == 0)
2769 		return (PFN_INVALID);
2770 
2771 	if (IN_VA_HOLE(vaddr))
2772 		return (PFN_INVALID);
2773 
2774 	XPV_DISALLOW_MIGRATE();
2775 	/*
2776 	 * A very common use of hat_getpfnum() is from the DDI for kernel pages.
2777 	 * Use the kmap_ptes (which also covers the 32 bit heap) to speed
2778 	 * this up.
2779 	 */
2780 	if (mmu.kmap_addr <= vaddr && vaddr < mmu.kmap_eaddr) {
2781 		x86pte_t pte;
2782 		pgcnt_t pg_index;
2783 
2784 		pg_index = mmu_btop(vaddr - mmu.kmap_addr);
2785 		pte = GET_PTE(PT_INDEX_PTR(mmu.kmap_ptes, pg_index));
2786 		if (PTE_ISVALID(pte))
2787 			/*LINTED [use of constant 0 causes a lint warning] */
2788 			pfn = PTE2PFN(pte, 0);
2789 		XPV_ALLOW_MIGRATE();
2790 		return (pfn);
2791 	}
2792 
2793 	ht = htable_getpage(hat, vaddr, &entry);
2794 	if (ht == NULL) {
2795 		XPV_ALLOW_MIGRATE();
2796 		return (PFN_INVALID);
2797 	}
2798 	ASSERT(vaddr >= ht->ht_vaddr);
2799 	ASSERT(vaddr <= HTABLE_LAST_PAGE(ht));
2800 	pfn = PTE2PFN(x86pte_get(ht, entry), ht->ht_level);
2801 	if (ht->ht_level > 0)
2802 		pfn += mmu_btop(vaddr & LEVEL_OFFSET(ht->ht_level));
2803 	htable_release(ht);
2804 	XPV_ALLOW_MIGRATE();
2805 	return (pfn);
2806 }
2807 
2808 /*
2809  * hat_getkpfnum() is an obsolete DDI routine, and its use is discouraged.
2810  * Use hat_getpfnum(kas.a_hat, ...) instead.
2811  *
2812  * We'd like to return PFN_INVALID if the mappings have underlying page_t's
2813  * but can't right now due to the fact that some software has grown to use
2814  * this interface incorrectly. So for now when the interface is misused,
2815  * return a warning to the user that in the future it won't work in the
2816  * way they're abusing it, and carry on.
2817  *
2818  * Note that hat_getkpfnum() is never supported on amd64.
2819  */
2820 #if !defined(__amd64)
2821 pfn_t
2822 hat_getkpfnum(caddr_t addr)
2823 {
2824 	pfn_t	pfn;
2825 	int badcaller = 0;
2826 
2827 	if (khat_running == 0)
2828 		panic("hat_getkpfnum(): called too early\n");
2829 	if ((uintptr_t)addr < kernelbase)
2830 		return (PFN_INVALID);
2831 
2832 	XPV_DISALLOW_MIGRATE();
2833 	if (segkpm && IS_KPM_ADDR(addr)) {
2834 		badcaller = 1;
2835 		pfn = hat_kpm_va2pfn(addr);
2836 	} else {
2837 		pfn = hat_getpfnum(kas.a_hat, addr);
2838 		badcaller = pf_is_memory(pfn);
2839 	}
2840 
2841 	if (badcaller)
2842 		hat_getkpfnum_badcall(caller());
2843 	XPV_ALLOW_MIGRATE();
2844 	return (pfn);
2845 }
2846 #endif /* __amd64 */
2847 
2848 /*
2849  * int hat_probe(hat, addr)
2850  *	return 0 if no valid mapping is present.  Faster version
2851  *	of hat_getattr in certain architectures.
2852  */
2853 int
2854 hat_probe(hat_t *hat, caddr_t addr)
2855 {
2856 	uintptr_t	vaddr = ALIGN2PAGE(addr);
2857 	uint_t		entry;
2858 	htable_t	*ht;
2859 	pgcnt_t		pg_off;
2860 
2861 	ASSERT(hat == kas.a_hat || vaddr <= _userlimit);
2862 	ASSERT(hat == kas.a_hat ||
2863 	    AS_LOCK_HELD(hat->hat_as, &hat->hat_as->a_lock));
2864 	if (IN_VA_HOLE(vaddr))
2865 		return (0);
2866 
2867 	/*
2868 	 * Most common use of hat_probe is from segmap. We special case it
2869 	 * for performance.
2870 	 */
2871 	if (mmu.kmap_addr <= vaddr && vaddr < mmu.kmap_eaddr) {
2872 		pg_off = mmu_btop(vaddr - mmu.kmap_addr);
2873 		if (mmu.pae_hat)
2874 			return (PTE_ISVALID(mmu.kmap_ptes[pg_off]));
2875 		else
2876 			return (PTE_ISVALID(
2877 			    ((x86pte32_t *)mmu.kmap_ptes)[pg_off]));
2878 	}
2879 
2880 	ht = htable_getpage(hat, vaddr, &entry);
2881 	htable_release(ht);
2882 	return (ht != NULL);
2883 }
2884 
2885 /*
2886  * Find out if the segment for hat_share()/hat_unshare() is DISM or locked ISM.
2887  */
2888 static int
2889 is_it_dism(hat_t *hat, caddr_t va)
2890 {
2891 	struct seg *seg;
2892 	struct shm_data *shmd;
2893 	struct spt_data *sptd;
2894 
2895 	seg = as_findseg(hat->hat_as, va, 0);
2896 	ASSERT(seg != NULL);
2897 	ASSERT(seg->s_base <= va);
2898 	shmd = (struct shm_data *)seg->s_data;
2899 	ASSERT(shmd != NULL);
2900 	sptd = (struct spt_data *)shmd->shm_sptseg->s_data;
2901 	ASSERT(sptd != NULL);
2902 	if (sptd->spt_flags & SHM_PAGEABLE)
2903 		return (1);
2904 	return (0);
2905 }
2906 
2907 /*
2908  * Simple implementation of ISM. hat_share() is similar to hat_memload_array(),
2909  * except that we use the ism_hat's existing mappings to determine the pages
2910  * and protections to use for this hat. If we find a full properly aligned
2911  * and sized pagetable, we will attempt to share the pagetable itself.
2912  */
2913 /*ARGSUSED*/
2914 int
2915 hat_share(
2916 	hat_t		*hat,
2917 	caddr_t		addr,
2918 	hat_t		*ism_hat,
2919 	caddr_t		src_addr,
2920 	size_t		len,	/* almost useless value, see below.. */
2921 	uint_t		ismszc)
2922 {
2923 	uintptr_t	vaddr_start = (uintptr_t)addr;
2924 	uintptr_t	vaddr;
2925 	uintptr_t	eaddr = vaddr_start + len;
2926 	uintptr_t	ism_addr_start = (uintptr_t)src_addr;
2927 	uintptr_t	ism_addr = ism_addr_start;
2928 	uintptr_t	e_ism_addr = ism_addr + len;
2929 	htable_t	*ism_ht = NULL;
2930 	htable_t	*ht;
2931 	x86pte_t	pte;
2932 	page_t		*pp;
2933 	pfn_t		pfn;
2934 	level_t		l;
2935 	pgcnt_t		pgcnt;
2936 	uint_t		prot;
2937 	int		is_dism;
2938 	int		flags;
2939 
2940 	/*
2941 	 * We might be asked to share an empty DISM hat by as_dup()
2942 	 */
2943 	ASSERT(hat != kas.a_hat);
2944 	ASSERT(eaddr <= _userlimit);
2945 	if (!(ism_hat->hat_flags & HAT_SHARED)) {
2946 		ASSERT(hat_get_mapped_size(ism_hat) == 0);
2947 		return (0);
2948 	}
2949 	XPV_DISALLOW_MIGRATE();
2950 
2951 	/*
2952 	 * The SPT segment driver often passes us a size larger than there are
2953 	 * valid mappings. That's because it rounds the segment size up to a
2954 	 * large pagesize, even if the actual memory mapped by ism_hat is less.
2955 	 */
2956 	ASSERT(IS_PAGEALIGNED(vaddr_start));
2957 	ASSERT(IS_PAGEALIGNED(ism_addr_start));
2958 	ASSERT(ism_hat->hat_flags & HAT_SHARED);
2959 	is_dism = is_it_dism(hat, addr);
2960 	while (ism_addr < e_ism_addr) {
2961 		/*
2962 		 * use htable_walk to get the next valid ISM mapping
2963 		 */
2964 		pte = htable_walk(ism_hat, &ism_ht, &ism_addr, e_ism_addr);
2965 		if (ism_ht == NULL)
2966 			break;
2967 
2968 		/*
2969 		 * First check to see if we already share the page table.
2970 		 */
2971 		l = ism_ht->ht_level;
2972 		vaddr = vaddr_start + (ism_addr - ism_addr_start);
2973 		ht = htable_lookup(hat, vaddr, l);
2974 		if (ht != NULL) {
2975 			if (ht->ht_flags & HTABLE_SHARED_PFN)
2976 				goto shared;
2977 			htable_release(ht);
2978 			goto not_shared;
2979 		}
2980 
2981 		/*
2982 		 * Can't ever share top table.
2983 		 */
2984 		if (l == mmu.max_level)
2985 			goto not_shared;
2986 
2987 		/*
2988 		 * Avoid level mismatches later due to DISM faults.
2989 		 */
2990 		if (is_dism && l > 0)
2991 			goto not_shared;
2992 
2993 		/*
2994 		 * addresses and lengths must align
2995 		 * table must be fully populated
2996 		 * no lower level page tables
2997 		 */
2998 		if (ism_addr != ism_ht->ht_vaddr ||
2999 		    (vaddr & LEVEL_OFFSET(l + 1)) != 0)
3000 			goto not_shared;
3001 
3002 		/*
3003 		 * The range of address space must cover a full table.
3004 		 */
3005 		if (e_ism_addr - ism_addr < LEVEL_SIZE(l + 1))
3006 			goto not_shared;
3007 
3008 		/*
3009 		 * All entries in the ISM page table must be leaf PTEs.
3010 		 */
3011 		if (l > 0) {
3012 			int e;
3013 
3014 			/*
3015 			 * We know the 0th is from htable_walk() above.
3016 			 */
3017 			for (e = 1; e < HTABLE_NUM_PTES(ism_ht); ++e) {
3018 				x86pte_t pte;
3019 				pte = x86pte_get(ism_ht, e);
3020 				if (!PTE_ISPAGE(pte, l))
3021 					goto not_shared;
3022 			}
3023 		}
3024 
3025 		/*
3026 		 * share the page table
3027 		 */
3028 		ht = htable_create(hat, vaddr, l, ism_ht);
3029 shared:
3030 		ASSERT(ht->ht_flags & HTABLE_SHARED_PFN);
3031 		ASSERT(ht->ht_shares == ism_ht);
3032 		hat->hat_ism_pgcnt +=
3033 		    (ism_ht->ht_valid_cnt - ht->ht_valid_cnt) <<
3034 		    (LEVEL_SHIFT(ht->ht_level) - MMU_PAGESHIFT);
3035 		ht->ht_valid_cnt = ism_ht->ht_valid_cnt;
3036 		htable_release(ht);
3037 		ism_addr = ism_ht->ht_vaddr + LEVEL_SIZE(l + 1);
3038 		htable_release(ism_ht);
3039 		ism_ht = NULL;
3040 		continue;
3041 
3042 not_shared:
3043 		/*
3044 		 * Unable to share the page table. Instead we will
3045 		 * create new mappings from the values in the ISM mappings.
3046 		 * Figure out what level size mappings to use;
3047 		 */
3048 		for (l = ism_ht->ht_level; l > 0; --l) {
3049 			if (LEVEL_SIZE(l) <= eaddr - vaddr &&
3050 			    (vaddr & LEVEL_OFFSET(l)) == 0)
3051 				break;
3052 		}
3053 
3054 		/*
3055 		 * The ISM mapping might be larger than the share area,
3056 		 * be careful to truncate it if needed.
3057 		 */
3058 		if (eaddr - vaddr >= LEVEL_SIZE(ism_ht->ht_level)) {
3059 			pgcnt = mmu_btop(LEVEL_SIZE(ism_ht->ht_level));
3060 		} else {
3061 			pgcnt = mmu_btop(eaddr - vaddr);
3062 			l = 0;
3063 		}
3064 
3065 		pfn = PTE2PFN(pte, ism_ht->ht_level);
3066 		ASSERT(pfn != PFN_INVALID);
3067 		while (pgcnt > 0) {
3068 			/*
3069 			 * Make a new pte for the PFN for this level.
3070 			 * Copy protections for the pte from the ISM pte.
3071 			 */
3072 			pp = page_numtopp_nolock(pfn);
3073 			ASSERT(pp != NULL);
3074 
3075 			prot = PROT_USER | PROT_READ | HAT_UNORDERED_OK;
3076 			if (PTE_GET(pte, PT_WRITABLE))
3077 				prot |= PROT_WRITE;
3078 			if (!PTE_GET(pte, PT_NX))
3079 				prot |= PROT_EXEC;
3080 
3081 			flags = HAT_LOAD;
3082 			if (!is_dism)
3083 				flags |= HAT_LOAD_LOCK | HAT_LOAD_NOCONSIST;
3084 			while (hati_load_common(hat, vaddr, pp, prot, flags,
3085 			    l, pfn) != 0) {
3086 				if (l == 0)
3087 					panic("hati_load_common() failure");
3088 				--l;
3089 			}
3090 
3091 			vaddr += LEVEL_SIZE(l);
3092 			ism_addr += LEVEL_SIZE(l);
3093 			pfn += mmu_btop(LEVEL_SIZE(l));
3094 			pgcnt -= mmu_btop(LEVEL_SIZE(l));
3095 		}
3096 	}
3097 	if (ism_ht != NULL)
3098 		htable_release(ism_ht);
3099 	XPV_ALLOW_MIGRATE();
3100 	return (0);
3101 }
3102 
3103 
3104 /*
3105  * hat_unshare() is similar to hat_unload_callback(), but
3106  * we have to look for empty shared pagetables. Note that
3107  * hat_unshare() is always invoked against an entire segment.
3108  */
3109 /*ARGSUSED*/
3110 void
3111 hat_unshare(hat_t *hat, caddr_t addr, size_t len, uint_t ismszc)
3112 {
3113 	uint64_t	vaddr = (uintptr_t)addr;
3114 	uintptr_t	eaddr = vaddr + len;
3115 	htable_t	*ht = NULL;
3116 	uint_t		need_demaps = 0;
3117 	int		flags = HAT_UNLOAD_UNMAP;
3118 	level_t		l;
3119 
3120 	ASSERT(hat != kas.a_hat);
3121 	ASSERT(eaddr <= _userlimit);
3122 	ASSERT(IS_PAGEALIGNED(vaddr));
3123 	ASSERT(IS_PAGEALIGNED(eaddr));
3124 	XPV_DISALLOW_MIGRATE();
3125 
3126 	/*
3127 	 * First go through and remove any shared pagetables.
3128 	 *
3129 	 * Note that it's ok to delay the TLB shootdown till the entire range is
3130 	 * finished, because if hat_pageunload() were to unload a shared
3131 	 * pagetable page, its hat_tlb_inval() will do a global TLB invalidate.
3132 	 */
3133 	l = mmu.max_page_level;
3134 	if (l == mmu.max_level)
3135 		--l;
3136 	for (; l >= 0; --l) {
3137 		for (vaddr = (uintptr_t)addr; vaddr < eaddr;
3138 		    vaddr = (vaddr & LEVEL_MASK(l + 1)) + LEVEL_SIZE(l + 1)) {
3139 			ASSERT(!IN_VA_HOLE(vaddr));
3140 			/*
3141 			 * find a pagetable that maps the current address
3142 			 */
3143 			ht = htable_lookup(hat, vaddr, l);
3144 			if (ht == NULL)
3145 				continue;
3146 			if (ht->ht_flags & HTABLE_SHARED_PFN) {
3147 				/*
3148 				 * clear page count, set valid_cnt to 0,
3149 				 * let htable_release() finish the job
3150 				 */
3151 				hat->hat_ism_pgcnt -= ht->ht_valid_cnt <<
3152 				    (LEVEL_SHIFT(ht->ht_level) - MMU_PAGESHIFT);
3153 				ht->ht_valid_cnt = 0;
3154 				need_demaps = 1;
3155 			}
3156 			htable_release(ht);
3157 		}
3158 	}
3159 
3160 	/*
3161 	 * flush the TLBs - since we're probably dealing with MANY mappings
3162 	 * we do just one CR3 reload.
3163 	 */
3164 	if (!(hat->hat_flags & HAT_FREEING) && need_demaps)
3165 		hat_tlb_inval(hat, DEMAP_ALL_ADDR);
3166 
3167 	/*
3168 	 * Now go back and clean up any unaligned mappings that
3169 	 * couldn't share pagetables.
3170 	 */
3171 	if (!is_it_dism(hat, addr))
3172 		flags |= HAT_UNLOAD_UNLOCK;
3173 	hat_unload(hat, addr, len, flags);
3174 	XPV_ALLOW_MIGRATE();
3175 }
3176 
3177 
3178 /*
3179  * hat_reserve() does nothing
3180  */
3181 /*ARGSUSED*/
3182 void
3183 hat_reserve(struct as *as, caddr_t addr, size_t len)
3184 {
3185 }
3186 
3187 
3188 /*
3189  * Called when all mappings to a page should have write permission removed.
3190  * Mostly stolen from hat_pagesync()
3191  */
3192 static void
3193 hati_page_clrwrt(struct page *pp)
3194 {
3195 	hment_t		*hm = NULL;
3196 	htable_t	*ht;
3197 	uint_t		entry;
3198 	x86pte_t	old;
3199 	x86pte_t	new;
3200 	uint_t		pszc = 0;
3201 
3202 	XPV_DISALLOW_MIGRATE();
3203 next_size:
3204 	/*
3205 	 * walk thru the mapping list clearing write permission
3206 	 */
3207 	x86_hm_enter(pp);
3208 	while ((hm = hment_walk(pp, &ht, &entry, hm)) != NULL) {
3209 		if (ht->ht_level < pszc)
3210 			continue;
3211 		old = x86pte_get(ht, entry);
3212 
3213 		for (;;) {
3214 			/*
3215 			 * Is this mapping of interest?
3216 			 */
3217 			if (PTE2PFN(old, ht->ht_level) != pp->p_pagenum ||
3218 			    PTE_GET(old, PT_WRITABLE) == 0)
3219 				break;
3220 
3221 			/*
3222 			 * Clear ref/mod writable bits. This requires cross
3223 			 * calls to ensure any executing TLBs see cleared bits.
3224 			 */
3225 			new = old;
3226 			PTE_CLR(new, PT_REF | PT_MOD | PT_WRITABLE);
3227 			old = hati_update_pte(ht, entry, old, new);
3228 			if (old != 0)
3229 				continue;
3230 
3231 			break;
3232 		}
3233 	}
3234 	x86_hm_exit(pp);
3235 	while (pszc < pp->p_szc) {
3236 		page_t *tpp;
3237 		pszc++;
3238 		tpp = PP_GROUPLEADER(pp, pszc);
3239 		if (pp != tpp) {
3240 			pp = tpp;
3241 			goto next_size;
3242 		}
3243 	}
3244 	XPV_ALLOW_MIGRATE();
3245 }
3246 
3247 /*
3248  * void hat_page_setattr(pp, flag)
3249  * void hat_page_clrattr(pp, flag)
3250  *	used to set/clr ref/mod bits.
3251  */
3252 void
3253 hat_page_setattr(struct page *pp, uint_t flag)
3254 {
3255 	vnode_t		*vp = pp->p_vnode;
3256 	kmutex_t	*vphm = NULL;
3257 	page_t		**listp;
3258 	int		noshuffle;
3259 
3260 	noshuffle = flag & P_NSH;
3261 	flag &= ~P_NSH;
3262 
3263 	if (PP_GETRM(pp, flag) == flag)
3264 		return;
3265 
3266 	if ((flag & P_MOD) != 0 && vp != NULL && IS_VMODSORT(vp) &&
3267 	    !noshuffle) {
3268 		vphm = page_vnode_mutex(vp);
3269 		mutex_enter(vphm);
3270 	}
3271 
3272 	PP_SETRM(pp, flag);
3273 
3274 	if (vphm != NULL) {
3275 
3276 		/*
3277 		 * Some File Systems examine v_pages for NULL w/o
3278 		 * grabbing the vphm mutex. Must not let it become NULL when
3279 		 * pp is the only page on the list.
3280 		 */
3281 		if (pp->p_vpnext != pp) {
3282 			page_vpsub(&vp->v_pages, pp);
3283 			if (vp->v_pages != NULL)
3284 				listp = &vp->v_pages->p_vpprev->p_vpnext;
3285 			else
3286 				listp = &vp->v_pages;
3287 			page_vpadd(listp, pp);
3288 		}
3289 		mutex_exit(vphm);
3290 	}
3291 }
3292 
3293 void
3294 hat_page_clrattr(struct page *pp, uint_t flag)
3295 {
3296 	vnode_t		*vp = pp->p_vnode;
3297 	ASSERT(!(flag & ~(P_MOD | P_REF | P_RO)));
3298 
3299 	/*
3300 	 * Caller is expected to hold page's io lock for VMODSORT to work
3301 	 * correctly with pvn_vplist_dirty() and pvn_getdirty() when mod
3302 	 * bit is cleared.
3303 	 * We don't have assert to avoid tripping some existing third party
3304 	 * code. The dirty page is moved back to top of the v_page list
3305 	 * after IO is done in pvn_write_done().
3306 	 */
3307 	PP_CLRRM(pp, flag);
3308 
3309 	if ((flag & P_MOD) != 0 && vp != NULL && IS_VMODSORT(vp)) {
3310 
3311 		/*
3312 		 * VMODSORT works by removing write permissions and getting
3313 		 * a fault when a page is made dirty. At this point
3314 		 * we need to remove write permission from all mappings
3315 		 * to this page.
3316 		 */
3317 		hati_page_clrwrt(pp);
3318 	}
3319 }
3320 
3321 /*
3322  *	If flag is specified, returns 0 if attribute is disabled
3323  *	and non zero if enabled.  If flag specifes multiple attributes
3324  *	then returns 0 if ALL attributes are disabled.  This is an advisory
3325  *	call.
3326  */
3327 uint_t
3328 hat_page_getattr(struct page *pp, uint_t flag)
3329 {
3330 	return (PP_GETRM(pp, flag));
3331 }
3332 
3333 
3334 /*
3335  * common code used by hat_pageunload() and hment_steal()
3336  */
3337 hment_t *
3338 hati_page_unmap(page_t *pp, htable_t *ht, uint_t entry)
3339 {
3340 	x86pte_t old_pte;
3341 	pfn_t pfn = pp->p_pagenum;
3342 	hment_t *hm;
3343 
3344 	/*
3345 	 * We need to acquire a hold on the htable in order to
3346 	 * do the invalidate. We know the htable must exist, since
3347 	 * unmap's don't release the htable until after removing any
3348 	 * hment. Having x86_hm_enter() keeps that from proceeding.
3349 	 */
3350 	htable_acquire(ht);
3351 
3352 	/*
3353 	 * Invalidate the PTE and remove the hment.
3354 	 */
3355 	old_pte = x86pte_inval(ht, entry, 0, NULL);
3356 	if (PTE2PFN(old_pte, ht->ht_level) != pfn) {
3357 		panic("x86pte_inval() failure found PTE = " FMT_PTE
3358 		    " pfn being unmapped is %lx ht=0x%lx entry=0x%x",
3359 		    old_pte, pfn, (uintptr_t)ht, entry);
3360 	}
3361 
3362 	/*
3363 	 * Clean up all the htable information for this mapping
3364 	 */
3365 	ASSERT(ht->ht_valid_cnt > 0);
3366 	HTABLE_DEC(ht->ht_valid_cnt);
3367 	PGCNT_DEC(ht->ht_hat, ht->ht_level);
3368 
3369 	/*
3370 	 * sync ref/mod bits to the page_t
3371 	 */
3372 	if (PTE_GET(old_pte, PT_SOFTWARE) < PT_NOSYNC)
3373 		hati_sync_pte_to_page(pp, old_pte, ht->ht_level);
3374 
3375 	/*
3376 	 * Remove the mapping list entry for this page.
3377 	 */
3378 	hm = hment_remove(pp, ht, entry);
3379 
3380 	/*
3381 	 * drop the mapping list lock so that we might free the
3382 	 * hment and htable.
3383 	 */
3384 	x86_hm_exit(pp);
3385 	htable_release(ht);
3386 	return (hm);
3387 }
3388 
3389 extern int	vpm_enable;
3390 /*
3391  * Unload all translations to a page. If the page is a subpage of a large
3392  * page, the large page mappings are also removed.
3393  *
3394  * The forceflags are unused.
3395  */
3396 
3397 /*ARGSUSED*/
3398 static int
3399 hati_pageunload(struct page *pp, uint_t pg_szcd, uint_t forceflag)
3400 {
3401 	page_t		*cur_pp = pp;
3402 	hment_t		*hm;
3403 	hment_t		*prev;
3404 	htable_t	*ht;
3405 	uint_t		entry;
3406 	level_t		level;
3407 
3408 	XPV_DISALLOW_MIGRATE();
3409 
3410 	/*
3411 	 * prevent recursion due to kmem_free()
3412 	 */
3413 	++curthread->t_hatdepth;
3414 	ASSERT(curthread->t_hatdepth < 16);
3415 
3416 #if defined(__amd64)
3417 	/*
3418 	 * clear the vpm ref.
3419 	 */
3420 	if (vpm_enable) {
3421 		pp->p_vpmref = 0;
3422 	}
3423 #endif
3424 	/*
3425 	 * The loop with next_size handles pages with multiple pagesize mappings
3426 	 */
3427 next_size:
3428 	for (;;) {
3429 
3430 		/*
3431 		 * Get a mapping list entry
3432 		 */
3433 		x86_hm_enter(cur_pp);
3434 		for (prev = NULL; ; prev = hm) {
3435 			hm = hment_walk(cur_pp, &ht, &entry, prev);
3436 			if (hm == NULL) {
3437 				x86_hm_exit(cur_pp);
3438 
3439 				/*
3440 				 * If not part of a larger page, we're done.
3441 				 */
3442 				if (cur_pp->p_szc <= pg_szcd) {
3443 					ASSERT(curthread->t_hatdepth > 0);
3444 					--curthread->t_hatdepth;
3445 					XPV_ALLOW_MIGRATE();
3446 					return (0);
3447 				}
3448 
3449 				/*
3450 				 * Else check the next larger page size.
3451 				 * hat_page_demote() may decrease p_szc
3452 				 * but that's ok we'll just take an extra
3453 				 * trip discover there're no larger mappings
3454 				 * and return.
3455 				 */
3456 				++pg_szcd;
3457 				cur_pp = PP_GROUPLEADER(cur_pp, pg_szcd);
3458 				goto next_size;
3459 			}
3460 
3461 			/*
3462 			 * If this mapping size matches, remove it.
3463 			 */
3464 			level = ht->ht_level;
3465 			if (level == pg_szcd)
3466 				break;
3467 		}
3468 
3469 		/*
3470 		 * Remove the mapping list entry for this page.
3471 		 * Note this does the x86_hm_exit() for us.
3472 		 */
3473 		hm = hati_page_unmap(cur_pp, ht, entry);
3474 		if (hm != NULL)
3475 			hment_free(hm);
3476 	}
3477 }
3478 
3479 int
3480 hat_pageunload(struct page *pp, uint_t forceflag)
3481 {
3482 	ASSERT(PAGE_EXCL(pp));
3483 	return (hati_pageunload(pp, 0, forceflag));
3484 }
3485 
3486 /*
3487  * Unload all large mappings to pp and reduce by 1 p_szc field of every large
3488  * page level that included pp.
3489  *
3490  * pp must be locked EXCL. Even though no other constituent pages are locked
3491  * it's legal to unload large mappings to pp because all constituent pages of
3492  * large locked mappings have to be locked SHARED.  therefore if we have EXCL
3493  * lock on one of constituent pages none of the large mappings to pp are
3494  * locked.
3495  *
3496  * Change (always decrease) p_szc field starting from the last constituent
3497  * page and ending with root constituent page so that root's pszc always shows
3498  * the area where hat_page_demote() may be active.
3499  *
3500  * This mechanism is only used for file system pages where it's not always
3501  * possible to get EXCL locks on all constituent pages to demote the size code
3502  * (as is done for anonymous or kernel large pages).
3503  */
3504 void
3505 hat_page_demote(page_t *pp)
3506 {
3507 	uint_t		pszc;
3508 	uint_t		rszc;
3509 	uint_t		szc;
3510 	page_t		*rootpp;
3511 	page_t		*firstpp;
3512 	page_t		*lastpp;
3513 	pgcnt_t		pgcnt;
3514 
3515 	ASSERT(PAGE_EXCL(pp));
3516 	ASSERT(!PP_ISFREE(pp));
3517 	ASSERT(page_szc_lock_assert(pp));
3518 
3519 	if (pp->p_szc == 0)
3520 		return;
3521 
3522 	rootpp = PP_GROUPLEADER(pp, 1);
3523 	(void) hati_pageunload(rootpp, 1, HAT_FORCE_PGUNLOAD);
3524 
3525 	/*
3526 	 * all large mappings to pp are gone
3527 	 * and no new can be setup since pp is locked exclusively.
3528 	 *
3529 	 * Lock the root to make sure there's only one hat_page_demote()
3530 	 * outstanding within the area of this root's pszc.
3531 	 *
3532 	 * Second potential hat_page_demote() is already eliminated by upper
3533 	 * VM layer via page_szc_lock() but we don't rely on it and use our
3534 	 * own locking (so that upper layer locking can be changed without
3535 	 * assumptions that hat depends on upper layer VM to prevent multiple
3536 	 * hat_page_demote() to be issued simultaneously to the same large
3537 	 * page).
3538 	 */
3539 again:
3540 	pszc = pp->p_szc;
3541 	if (pszc == 0)
3542 		return;
3543 	rootpp = PP_GROUPLEADER(pp, pszc);
3544 	x86_hm_enter(rootpp);
3545 	/*
3546 	 * If root's p_szc is different from pszc we raced with another
3547 	 * hat_page_demote().  Drop the lock and try to find the root again.
3548 	 * If root's p_szc is greater than pszc previous hat_page_demote() is
3549 	 * not done yet.  Take and release mlist lock of root's root to wait
3550 	 * for previous hat_page_demote() to complete.
3551 	 */
3552 	if ((rszc = rootpp->p_szc) != pszc) {
3553 		x86_hm_exit(rootpp);
3554 		if (rszc > pszc) {
3555 			/* p_szc of a locked non free page can't increase */
3556 			ASSERT(pp != rootpp);
3557 
3558 			rootpp = PP_GROUPLEADER(rootpp, rszc);
3559 			x86_hm_enter(rootpp);
3560 			x86_hm_exit(rootpp);
3561 		}
3562 		goto again;
3563 	}
3564 	ASSERT(pp->p_szc == pszc);
3565 
3566 	/*
3567 	 * Decrement by 1 p_szc of every constituent page of a region that
3568 	 * covered pp. For example if original szc is 3 it gets changed to 2
3569 	 * everywhere except in region 2 that covered pp. Region 2 that
3570 	 * covered pp gets demoted to 1 everywhere except in region 1 that
3571 	 * covered pp. The region 1 that covered pp is demoted to region
3572 	 * 0. It's done this way because from region 3 we removed level 3
3573 	 * mappings, from region 2 that covered pp we removed level 2 mappings
3574 	 * and from region 1 that covered pp we removed level 1 mappings.  All
3575 	 * changes are done from from high pfn's to low pfn's so that roots
3576 	 * are changed last allowing one to know the largest region where
3577 	 * hat_page_demote() is stil active by only looking at the root page.
3578 	 *
3579 	 * This algorithm is implemented in 2 while loops. First loop changes
3580 	 * p_szc of pages to the right of pp's level 1 region and second
3581 	 * loop changes p_szc of pages of level 1 region that covers pp
3582 	 * and all pages to the left of level 1 region that covers pp.
3583 	 * In the first loop p_szc keeps dropping with every iteration
3584 	 * and in the second loop it keeps increasing with every iteration.
3585 	 *
3586 	 * First loop description: Demote pages to the right of pp outside of
3587 	 * level 1 region that covers pp.  In every iteration of the while
3588 	 * loop below find the last page of szc region and the first page of
3589 	 * (szc - 1) region that is immediately to the right of (szc - 1)
3590 	 * region that covers pp.  From last such page to first such page
3591 	 * change every page's szc to szc - 1. Decrement szc and continue
3592 	 * looping until szc is 1. If pp belongs to the last (szc - 1) region
3593 	 * of szc region skip to the next iteration.
3594 	 */
3595 	szc = pszc;
3596 	while (szc > 1) {
3597 		lastpp = PP_GROUPLEADER(pp, szc);
3598 		pgcnt = page_get_pagecnt(szc);
3599 		lastpp += pgcnt - 1;
3600 		firstpp = PP_GROUPLEADER(pp, (szc - 1));
3601 		pgcnt = page_get_pagecnt(szc - 1);
3602 		if (lastpp - firstpp < pgcnt) {
3603 			szc--;
3604 			continue;
3605 		}
3606 		firstpp += pgcnt;
3607 		while (lastpp != firstpp) {
3608 			ASSERT(lastpp->p_szc == pszc);
3609 			lastpp->p_szc = szc - 1;
3610 			lastpp--;
3611 		}
3612 		firstpp->p_szc = szc - 1;
3613 		szc--;
3614 	}
3615 
3616 	/*
3617 	 * Second loop description:
3618 	 * First iteration changes p_szc to 0 of every
3619 	 * page of level 1 region that covers pp.
3620 	 * Subsequent iterations find last page of szc region
3621 	 * immediately to the left of szc region that covered pp
3622 	 * and first page of (szc + 1) region that covers pp.
3623 	 * From last to first page change p_szc of every page to szc.
3624 	 * Increment szc and continue looping until szc is pszc.
3625 	 * If pp belongs to the fist szc region of (szc + 1) region
3626 	 * skip to the next iteration.
3627 	 *
3628 	 */
3629 	szc = 0;
3630 	while (szc < pszc) {
3631 		firstpp = PP_GROUPLEADER(pp, (szc + 1));
3632 		if (szc == 0) {
3633 			pgcnt = page_get_pagecnt(1);
3634 			lastpp = firstpp + (pgcnt - 1);
3635 		} else {
3636 			lastpp = PP_GROUPLEADER(pp, szc);
3637 			if (firstpp == lastpp) {
3638 				szc++;
3639 				continue;
3640 			}
3641 			lastpp--;
3642 			pgcnt = page_get_pagecnt(szc);
3643 		}
3644 		while (lastpp != firstpp) {
3645 			ASSERT(lastpp->p_szc == pszc);
3646 			lastpp->p_szc = szc;
3647 			lastpp--;
3648 		}
3649 		firstpp->p_szc = szc;
3650 		if (firstpp == rootpp)
3651 			break;
3652 		szc++;
3653 	}
3654 	x86_hm_exit(rootpp);
3655 }
3656 
3657 /*
3658  * get hw stats from hardware into page struct and reset hw stats
3659  * returns attributes of page
3660  * Flags for hat_pagesync, hat_getstat, hat_sync
3661  *
3662  * define	HAT_SYNC_ZERORM		0x01
3663  *
3664  * Additional flags for hat_pagesync
3665  *
3666  * define	HAT_SYNC_STOPON_REF	0x02
3667  * define	HAT_SYNC_STOPON_MOD	0x04
3668  * define	HAT_SYNC_STOPON_RM	0x06
3669  * define	HAT_SYNC_STOPON_SHARED	0x08
3670  */
3671 uint_t
3672 hat_pagesync(struct page *pp, uint_t flags)
3673 {
3674 	hment_t		*hm = NULL;
3675 	htable_t	*ht;
3676 	uint_t		entry;
3677 	x86pte_t	old, save_old;
3678 	x86pte_t	new;
3679 	uchar_t		nrmbits = P_REF|P_MOD|P_RO;
3680 	extern ulong_t	po_share;
3681 	page_t		*save_pp = pp;
3682 	uint_t		pszc = 0;
3683 
3684 	ASSERT(PAGE_LOCKED(pp) || panicstr);
3685 
3686 	if (PP_ISRO(pp) && (flags & HAT_SYNC_STOPON_MOD))
3687 		return (pp->p_nrm & nrmbits);
3688 
3689 	if ((flags & HAT_SYNC_ZERORM) == 0) {
3690 
3691 		if ((flags & HAT_SYNC_STOPON_REF) != 0 && PP_ISREF(pp))
3692 			return (pp->p_nrm & nrmbits);
3693 
3694 		if ((flags & HAT_SYNC_STOPON_MOD) != 0 && PP_ISMOD(pp))
3695 			return (pp->p_nrm & nrmbits);
3696 
3697 		if ((flags & HAT_SYNC_STOPON_SHARED) != 0 &&
3698 		    hat_page_getshare(pp) > po_share) {
3699 			if (PP_ISRO(pp))
3700 				PP_SETREF(pp);
3701 			return (pp->p_nrm & nrmbits);
3702 		}
3703 	}
3704 
3705 	XPV_DISALLOW_MIGRATE();
3706 next_size:
3707 	/*
3708 	 * walk thru the mapping list syncing (and clearing) ref/mod bits.
3709 	 */
3710 	x86_hm_enter(pp);
3711 	while ((hm = hment_walk(pp, &ht, &entry, hm)) != NULL) {
3712 		if (ht->ht_level < pszc)
3713 			continue;
3714 		old = x86pte_get(ht, entry);
3715 try_again:
3716 
3717 		ASSERT(PTE2PFN(old, ht->ht_level) == pp->p_pagenum);
3718 
3719 		if (PTE_GET(old, PT_REF | PT_MOD) == 0)
3720 			continue;
3721 
3722 		save_old = old;
3723 		if ((flags & HAT_SYNC_ZERORM) != 0) {
3724 
3725 			/*
3726 			 * Need to clear ref or mod bits. Need to demap
3727 			 * to make sure any executing TLBs see cleared bits.
3728 			 */
3729 			new = old;
3730 			PTE_CLR(new, PT_REF | PT_MOD);
3731 			old = hati_update_pte(ht, entry, old, new);
3732 			if (old != 0)
3733 				goto try_again;
3734 
3735 			old = save_old;
3736 		}
3737 
3738 		/*
3739 		 * Sync the PTE
3740 		 */
3741 		if (!(flags & HAT_SYNC_ZERORM) &&
3742 		    PTE_GET(old, PT_SOFTWARE) <= PT_NOSYNC)
3743 			hati_sync_pte_to_page(pp, old, ht->ht_level);
3744 
3745 		/*
3746 		 * can stop short if we found a ref'd or mod'd page
3747 		 */
3748 		if ((flags & HAT_SYNC_STOPON_MOD) && PP_ISMOD(save_pp) ||
3749 		    (flags & HAT_SYNC_STOPON_REF) && PP_ISREF(save_pp)) {
3750 			x86_hm_exit(pp);
3751 			goto done;
3752 		}
3753 	}
3754 	x86_hm_exit(pp);
3755 	while (pszc < pp->p_szc) {
3756 		page_t *tpp;
3757 		pszc++;
3758 		tpp = PP_GROUPLEADER(pp, pszc);
3759 		if (pp != tpp) {
3760 			pp = tpp;
3761 			goto next_size;
3762 		}
3763 	}
3764 done:
3765 	XPV_ALLOW_MIGRATE();
3766 	return (save_pp->p_nrm & nrmbits);
3767 }
3768 
3769 /*
3770  * returns approx number of mappings to this pp.  A return of 0 implies
3771  * there are no mappings to the page.
3772  */
3773 ulong_t
3774 hat_page_getshare(page_t *pp)
3775 {
3776 	uint_t cnt;
3777 	cnt = hment_mapcnt(pp);
3778 #if defined(__amd64)
3779 	if (vpm_enable && pp->p_vpmref) {
3780 		cnt += 1;
3781 	}
3782 #endif
3783 	return (cnt);
3784 }
3785 
3786 /*
3787  * Return 1 the number of mappings exceeds sh_thresh. Return 0
3788  * otherwise.
3789  */
3790 int
3791 hat_page_checkshare(page_t *pp, ulong_t sh_thresh)
3792 {
3793 	return (hat_page_getshare(pp) > sh_thresh);
3794 }
3795 
3796 /*
3797  * hat_softlock isn't supported anymore
3798  */
3799 /*ARGSUSED*/
3800 faultcode_t
3801 hat_softlock(
3802 	hat_t *hat,
3803 	caddr_t addr,
3804 	size_t *len,
3805 	struct page **page_array,
3806 	uint_t flags)
3807 {
3808 	return (FC_NOSUPPORT);
3809 }
3810 
3811 
3812 
3813 /*
3814  * Routine to expose supported HAT features to platform independent code.
3815  */
3816 /*ARGSUSED*/
3817 int
3818 hat_supported(enum hat_features feature, void *arg)
3819 {
3820 	switch (feature) {
3821 
3822 	case HAT_SHARED_PT:	/* this is really ISM */
3823 		return (1);
3824 
3825 	case HAT_DYNAMIC_ISM_UNMAP:
3826 		return (0);
3827 
3828 	case HAT_VMODSORT:
3829 		return (1);
3830 
3831 	case HAT_SHARED_REGIONS:
3832 		return (0);
3833 
3834 	default:
3835 		panic("hat_supported() - unknown feature");
3836 	}
3837 	return (0);
3838 }
3839 
3840 /*
3841  * Called when a thread is exiting and has been switched to the kernel AS
3842  */
3843 void
3844 hat_thread_exit(kthread_t *thd)
3845 {
3846 	ASSERT(thd->t_procp->p_as == &kas);
3847 	XPV_DISALLOW_MIGRATE();
3848 	hat_switch(thd->t_procp->p_as->a_hat);
3849 	XPV_ALLOW_MIGRATE();
3850 }
3851 
3852 /*
3853  * Setup the given brand new hat structure as the new HAT on this cpu's mmu.
3854  */
3855 /*ARGSUSED*/
3856 void
3857 hat_setup(hat_t *hat, int flags)
3858 {
3859 	XPV_DISALLOW_MIGRATE();
3860 	kpreempt_disable();
3861 
3862 	hat_switch(hat);
3863 
3864 	kpreempt_enable();
3865 	XPV_ALLOW_MIGRATE();
3866 }
3867 
3868 /*
3869  * Prepare for a CPU private mapping for the given address.
3870  *
3871  * The address can only be used from a single CPU and can be remapped
3872  * using hat_mempte_remap().  Return the address of the PTE.
3873  *
3874  * We do the htable_create() if necessary and increment the valid count so
3875  * the htable can't disappear.  We also hat_devload() the page table into
3876  * kernel so that the PTE is quickly accessed.
3877  */
3878 hat_mempte_t
3879 hat_mempte_setup(caddr_t addr)
3880 {
3881 	uintptr_t	va = (uintptr_t)addr;
3882 	htable_t	*ht;
3883 	uint_t		entry;
3884 	x86pte_t	oldpte;
3885 	hat_mempte_t	p;
3886 
3887 	ASSERT(IS_PAGEALIGNED(va));
3888 	ASSERT(!IN_VA_HOLE(va));
3889 	++curthread->t_hatdepth;
3890 	XPV_DISALLOW_MIGRATE();
3891 	ht = htable_getpte(kas.a_hat, va, &entry, &oldpte, 0);
3892 	if (ht == NULL) {
3893 		ht = htable_create(kas.a_hat, va, 0, NULL);
3894 		entry = htable_va2entry(va, ht);
3895 		ASSERT(ht->ht_level == 0);
3896 		oldpte = x86pte_get(ht, entry);
3897 	}
3898 	if (PTE_ISVALID(oldpte))
3899 		panic("hat_mempte_setup(): address already mapped"
3900 		    "ht=%p, entry=%d, pte=" FMT_PTE, (void *)ht, entry, oldpte);
3901 
3902 	/*
3903 	 * increment ht_valid_cnt so that the pagetable can't disappear
3904 	 */
3905 	HTABLE_INC(ht->ht_valid_cnt);
3906 
3907 	/*
3908 	 * return the PTE physical address to the caller.
3909 	 */
3910 	htable_release(ht);
3911 	XPV_ALLOW_MIGRATE();
3912 	p = PT_INDEX_PHYSADDR(pfn_to_pa(ht->ht_pfn), entry);
3913 	--curthread->t_hatdepth;
3914 	return (p);
3915 }
3916 
3917 /*
3918  * Release a CPU private mapping for the given address.
3919  * We decrement the htable valid count so it might be destroyed.
3920  */
3921 /*ARGSUSED1*/
3922 void
3923 hat_mempte_release(caddr_t addr, hat_mempte_t pte_pa)
3924 {
3925 	htable_t	*ht;
3926 
3927 	XPV_DISALLOW_MIGRATE();
3928 	/*
3929 	 * invalidate any left over mapping and decrement the htable valid count
3930 	 */
3931 #ifdef __xpv
3932 	if (HYPERVISOR_update_va_mapping((uintptr_t)addr, 0,
3933 	    UVMF_INVLPG | UVMF_LOCAL))
3934 		panic("HYPERVISOR_update_va_mapping() failed");
3935 #else
3936 	{
3937 		x86pte_t *pteptr;
3938 
3939 		pteptr = x86pte_mapin(mmu_btop(pte_pa),
3940 		    (pte_pa & MMU_PAGEOFFSET) >> mmu.pte_size_shift, NULL);
3941 		if (mmu.pae_hat)
3942 			*pteptr = 0;
3943 		else
3944 			*(x86pte32_t *)pteptr = 0;
3945 		mmu_tlbflush_entry(addr);
3946 		x86pte_mapout();
3947 	}
3948 #endif
3949 
3950 	ht = htable_getpte(kas.a_hat, ALIGN2PAGE(addr), NULL, NULL, 0);
3951 	if (ht == NULL)
3952 		panic("hat_mempte_release(): invalid address");
3953 	ASSERT(ht->ht_level == 0);
3954 	HTABLE_DEC(ht->ht_valid_cnt);
3955 	htable_release(ht);
3956 	XPV_ALLOW_MIGRATE();
3957 }
3958 
3959 /*
3960  * Apply a temporary CPU private mapping to a page. We flush the TLB only
3961  * on this CPU, so this ought to have been called with preemption disabled.
3962  */
3963 void
3964 hat_mempte_remap(
3965 	pfn_t		pfn,
3966 	caddr_t		addr,
3967 	hat_mempte_t	pte_pa,
3968 	uint_t		attr,
3969 	uint_t		flags)
3970 {
3971 	uintptr_t	va = (uintptr_t)addr;
3972 	x86pte_t	pte;
3973 
3974 	/*
3975 	 * Remap the given PTE to the new page's PFN. Invalidate only
3976 	 * on this CPU.
3977 	 */
3978 #ifdef DEBUG
3979 	htable_t	*ht;
3980 	uint_t		entry;
3981 
3982 	ASSERT(IS_PAGEALIGNED(va));
3983 	ASSERT(!IN_VA_HOLE(va));
3984 	ht = htable_getpte(kas.a_hat, va, &entry, NULL, 0);
3985 	ASSERT(ht != NULL);
3986 	ASSERT(ht->ht_level == 0);
3987 	ASSERT(ht->ht_valid_cnt > 0);
3988 	ASSERT(ht->ht_pfn == mmu_btop(pte_pa));
3989 	htable_release(ht);
3990 #endif
3991 	XPV_DISALLOW_MIGRATE();
3992 	pte = hati_mkpte(pfn, attr, 0, flags);
3993 #ifdef __xpv
3994 	if (HYPERVISOR_update_va_mapping(va, pte, UVMF_INVLPG | UVMF_LOCAL))
3995 		panic("HYPERVISOR_update_va_mapping() failed");
3996 #else
3997 	{
3998 		x86pte_t *pteptr;
3999 
4000 		pteptr = x86pte_mapin(mmu_btop(pte_pa),
4001 		    (pte_pa & MMU_PAGEOFFSET) >> mmu.pte_size_shift, NULL);
4002 		if (mmu.pae_hat)
4003 			*(x86pte_t *)pteptr = pte;
4004 		else
4005 			*(x86pte32_t *)pteptr = (x86pte32_t)pte;
4006 		mmu_tlbflush_entry(addr);
4007 		x86pte_mapout();
4008 	}
4009 #endif
4010 	XPV_ALLOW_MIGRATE();
4011 }
4012 
4013 
4014 
4015 /*
4016  * Hat locking functions
4017  * XXX - these two functions are currently being used by hatstats
4018  * 	they can be removed by using a per-as mutex for hatstats.
4019  */
4020 void
4021 hat_enter(hat_t *hat)
4022 {
4023 	mutex_enter(&hat->hat_mutex);
4024 }
4025 
4026 void
4027 hat_exit(hat_t *hat)
4028 {
4029 	mutex_exit(&hat->hat_mutex);
4030 }
4031 
4032 /*
4033  * HAT part of cpu initialization.
4034  */
4035 void
4036 hat_cpu_online(struct cpu *cpup)
4037 {
4038 	if (cpup != CPU) {
4039 		x86pte_cpu_init(cpup);
4040 		hat_vlp_setup(cpup);
4041 	}
4042 	CPUSET_ATOMIC_ADD(khat_cpuset, cpup->cpu_id);
4043 }
4044 
4045 /*
4046  * HAT part of cpu deletion.
4047  * (currently, we only call this after the cpu is safely passivated.)
4048  */
4049 void
4050 hat_cpu_offline(struct cpu *cpup)
4051 {
4052 	ASSERT(cpup != CPU);
4053 
4054 	CPUSET_ATOMIC_DEL(khat_cpuset, cpup->cpu_id);
4055 	hat_vlp_teardown(cpup);
4056 	x86pte_cpu_fini(cpup);
4057 }
4058 
4059 /*
4060  * Function called after all CPUs are brought online.
4061  * Used to remove low address boot mappings.
4062  */
4063 void
4064 clear_boot_mappings(uintptr_t low, uintptr_t high)
4065 {
4066 	uintptr_t vaddr = low;
4067 	htable_t *ht = NULL;
4068 	level_t level;
4069 	uint_t entry;
4070 	x86pte_t pte;
4071 
4072 	/*
4073 	 * On 1st CPU we can unload the prom mappings, basically we blow away
4074 	 * all virtual mappings under _userlimit.
4075 	 */
4076 	while (vaddr < high) {
4077 		pte = htable_walk(kas.a_hat, &ht, &vaddr, high);
4078 		if (ht == NULL)
4079 			break;
4080 
4081 		level = ht->ht_level;
4082 		entry = htable_va2entry(vaddr, ht);
4083 		ASSERT(level <= mmu.max_page_level);
4084 		ASSERT(PTE_ISPAGE(pte, level));
4085 
4086 		/*
4087 		 * Unload the mapping from the page tables.
4088 		 */
4089 		(void) x86pte_inval(ht, entry, 0, NULL);
4090 		ASSERT(ht->ht_valid_cnt > 0);
4091 		HTABLE_DEC(ht->ht_valid_cnt);
4092 		PGCNT_DEC(ht->ht_hat, ht->ht_level);
4093 
4094 		vaddr += LEVEL_SIZE(ht->ht_level);
4095 	}
4096 	if (ht)
4097 		htable_release(ht);
4098 }
4099 
4100 /*
4101  * Atomically update a new translation for a single page.  If the
4102  * currently installed PTE doesn't match the value we expect to find,
4103  * it's not updated and we return the PTE we found.
4104  *
4105  * If activating nosync or NOWRITE and the page was modified we need to sync
4106  * with the page_t. Also sync with page_t if clearing ref/mod bits.
4107  */
4108 static x86pte_t
4109 hati_update_pte(htable_t *ht, uint_t entry, x86pte_t expected, x86pte_t new)
4110 {
4111 	page_t		*pp;
4112 	uint_t		rm = 0;
4113 	x86pte_t	replaced;
4114 
4115 	if (PTE_GET(expected, PT_SOFTWARE) < PT_NOSYNC &&
4116 	    PTE_GET(expected, PT_MOD | PT_REF) &&
4117 	    (PTE_GET(new, PT_NOSYNC) || !PTE_GET(new, PT_WRITABLE) ||
4118 	    !PTE_GET(new, PT_MOD | PT_REF))) {
4119 
4120 		ASSERT(!pfn_is_foreign(PTE2PFN(expected, ht->ht_level)));
4121 		pp = page_numtopp_nolock(PTE2PFN(expected, ht->ht_level));
4122 		ASSERT(pp != NULL);
4123 		if (PTE_GET(expected, PT_MOD))
4124 			rm |= P_MOD;
4125 		if (PTE_GET(expected, PT_REF))
4126 			rm |= P_REF;
4127 		PTE_CLR(new, PT_MOD | PT_REF);
4128 	}
4129 
4130 	replaced = x86pte_update(ht, entry, expected, new);
4131 	if (replaced != expected)
4132 		return (replaced);
4133 
4134 	if (rm) {
4135 		/*
4136 		 * sync to all constituent pages of a large page
4137 		 */
4138 		pgcnt_t pgcnt = page_get_pagecnt(ht->ht_level);
4139 		ASSERT(IS_P2ALIGNED(pp->p_pagenum, pgcnt));
4140 		while (pgcnt-- > 0) {
4141 			/*
4142 			 * hat_page_demote() can't decrease
4143 			 * pszc below this mapping size
4144 			 * since large mapping existed after we
4145 			 * took mlist lock.
4146 			 */
4147 			ASSERT(pp->p_szc >= ht->ht_level);
4148 			hat_page_setattr(pp, rm);
4149 			++pp;
4150 		}
4151 	}
4152 
4153 	return (0);
4154 }
4155 
4156 /* ARGSUSED */
4157 void
4158 hat_join_srd(struct hat *hat, vnode_t *evp)
4159 {
4160 }
4161 
4162 /* ARGSUSED */
4163 hat_region_cookie_t
4164 hat_join_region(struct hat *hat,
4165     caddr_t r_saddr,
4166     size_t r_size,
4167     void *r_obj,
4168     u_offset_t r_objoff,
4169     uchar_t r_perm,
4170     uchar_t r_pgszc,
4171     hat_rgn_cb_func_t r_cb_function,
4172     uint_t flags)
4173 {
4174 	panic("No shared region support on x86");
4175 	return (HAT_INVALID_REGION_COOKIE);
4176 }
4177 
4178 /* ARGSUSED */
4179 void
4180 hat_leave_region(struct hat *hat, hat_region_cookie_t rcookie, uint_t flags)
4181 {
4182 	panic("No shared region support on x86");
4183 }
4184 
4185 /* ARGSUSED */
4186 void
4187 hat_dup_region(struct hat *hat, hat_region_cookie_t rcookie)
4188 {
4189 	panic("No shared region support on x86");
4190 }
4191 
4192 
4193 /*
4194  * Kernel Physical Mapping (kpm) facility
4195  *
4196  * Most of the routines needed to support segkpm are almost no-ops on the
4197  * x86 platform.  We map in the entire segment when it is created and leave
4198  * it mapped in, so there is no additional work required to set up and tear
4199  * down individual mappings.  All of these routines were created to support
4200  * SPARC platforms that have to avoid aliasing in their virtually indexed
4201  * caches.
4202  *
4203  * Most of the routines have sanity checks in them (e.g. verifying that the
4204  * passed-in page is locked).  We don't actually care about most of these
4205  * checks on x86, but we leave them in place to identify problems in the
4206  * upper levels.
4207  */
4208 
4209 /*
4210  * Map in a locked page and return the vaddr.
4211  */
4212 /*ARGSUSED*/
4213 caddr_t
4214 hat_kpm_mapin(struct page *pp, struct kpme *kpme)
4215 {
4216 	caddr_t		vaddr;
4217 
4218 #ifdef DEBUG
4219 	if (kpm_enable == 0) {
4220 		cmn_err(CE_WARN, "hat_kpm_mapin: kpm_enable not set\n");
4221 		return ((caddr_t)NULL);
4222 	}
4223 
4224 	if (pp == NULL || PAGE_LOCKED(pp) == 0) {
4225 		cmn_err(CE_WARN, "hat_kpm_mapin: pp zero or not locked\n");
4226 		return ((caddr_t)NULL);
4227 	}
4228 #endif
4229 
4230 	vaddr = hat_kpm_page2va(pp, 1);
4231 
4232 	return (vaddr);
4233 }
4234 
4235 /*
4236  * Mapout a locked page.
4237  */
4238 /*ARGSUSED*/
4239 void
4240 hat_kpm_mapout(struct page *pp, struct kpme *kpme, caddr_t vaddr)
4241 {
4242 #ifdef DEBUG
4243 	if (kpm_enable == 0) {
4244 		cmn_err(CE_WARN, "hat_kpm_mapout: kpm_enable not set\n");
4245 		return;
4246 	}
4247 
4248 	if (IS_KPM_ADDR(vaddr) == 0) {
4249 		cmn_err(CE_WARN, "hat_kpm_mapout: no kpm address\n");
4250 		return;
4251 	}
4252 
4253 	if (pp == NULL || PAGE_LOCKED(pp) == 0) {
4254 		cmn_err(CE_WARN, "hat_kpm_mapout: page zero or not locked\n");
4255 		return;
4256 	}
4257 #endif
4258 }
4259 
4260 /*
4261  * hat_kpm_mapin_pfn is used to obtain a kpm mapping for physical
4262  * memory addresses that are not described by a page_t.  It can
4263  * also be used for normal pages that are not locked, but beware
4264  * this is dangerous - no locking is performed, so the identity of
4265  * the page could change.  hat_kpm_mapin_pfn is not supported when
4266  * vac_colors > 1, because the chosen va depends on the page identity,
4267  * which could change.
4268  * The caller must only pass pfn's for valid physical addresses; violation
4269  * of this rule will cause panic.
4270  */
4271 caddr_t
4272 hat_kpm_mapin_pfn(pfn_t pfn)
4273 {
4274 	caddr_t paddr, vaddr;
4275 
4276 	if (kpm_enable == 0)
4277 		return ((caddr_t)NULL);
4278 
4279 	paddr = (caddr_t)ptob(pfn);
4280 	vaddr = (uintptr_t)kpm_vbase + paddr;
4281 
4282 	return ((caddr_t)vaddr);
4283 }
4284 
4285 /*ARGSUSED*/
4286 void
4287 hat_kpm_mapout_pfn(pfn_t pfn)
4288 {
4289 	/* empty */
4290 }
4291 
4292 /*
4293  * Return the kpm virtual address for a specific pfn
4294  */
4295 caddr_t
4296 hat_kpm_pfn2va(pfn_t pfn)
4297 {
4298 	uintptr_t vaddr = (uintptr_t)kpm_vbase + mmu_ptob(pfn);
4299 
4300 	ASSERT(!pfn_is_foreign(pfn));
4301 	return ((caddr_t)vaddr);
4302 }
4303 
4304 /*
4305  * Return the kpm virtual address for the page at pp.
4306  */
4307 /*ARGSUSED*/
4308 caddr_t
4309 hat_kpm_page2va(struct page *pp, int checkswap)
4310 {
4311 	return (hat_kpm_pfn2va(pp->p_pagenum));
4312 }
4313 
4314 /*
4315  * Return the page frame number for the kpm virtual address vaddr.
4316  */
4317 pfn_t
4318 hat_kpm_va2pfn(caddr_t vaddr)
4319 {
4320 	pfn_t		pfn;
4321 
4322 	ASSERT(IS_KPM_ADDR(vaddr));
4323 
4324 	pfn = (pfn_t)btop(vaddr - kpm_vbase);
4325 
4326 	return (pfn);
4327 }
4328 
4329 
4330 /*
4331  * Return the page for the kpm virtual address vaddr.
4332  */
4333 page_t *
4334 hat_kpm_vaddr2page(caddr_t vaddr)
4335 {
4336 	pfn_t		pfn;
4337 
4338 	ASSERT(IS_KPM_ADDR(vaddr));
4339 
4340 	pfn = hat_kpm_va2pfn(vaddr);
4341 
4342 	return (page_numtopp_nolock(pfn));
4343 }
4344 
4345 /*
4346  * hat_kpm_fault is called from segkpm_fault when we take a page fault on a
4347  * KPM page.  This should never happen on x86
4348  */
4349 int
4350 hat_kpm_fault(hat_t *hat, caddr_t vaddr)
4351 {
4352 	panic("pagefault in seg_kpm.  hat: 0x%p  vaddr: 0x%p",
4353 	    (void *)hat, (void *)vaddr);
4354 
4355 	return (0);
4356 }
4357 
4358 /*ARGSUSED*/
4359 void
4360 hat_kpm_mseghash_clear(int nentries)
4361 {}
4362 
4363 /*ARGSUSED*/
4364 void
4365 hat_kpm_mseghash_update(pgcnt_t inx, struct memseg *msp)
4366 {}
4367 
4368 #ifndef	__xpv
4369 void
4370 hat_kpm_addmem_mseg_update(struct memseg *msp, pgcnt_t nkpmpgs,
4371 	offset_t kpm_pages_off)
4372 {
4373 	_NOTE(ARGUNUSED(nkpmpgs, kpm_pages_off));
4374 	pfn_t base, end;
4375 
4376 	/*
4377 	 * kphysm_add_memory_dynamic() does not set nkpmpgs
4378 	 * when page_t memory is externally allocated.  That
4379 	 * code must properly calculate nkpmpgs in all cases
4380 	 * if nkpmpgs needs to be used at some point.
4381 	 */
4382 
4383 	/*
4384 	 * The meta (page_t) pages for dynamically added memory are allocated
4385 	 * either from the incoming memory itself or from existing memory.
4386 	 * In the former case the base of the incoming pages will be different
4387 	 * than the base of the dynamic segment so call memseg_get_start() to
4388 	 * get the actual base of the incoming memory for each case.
4389 	 */
4390 
4391 	base = memseg_get_start(msp);
4392 	end = msp->pages_end;
4393 
4394 	hat_devload(kas.a_hat, kpm_vbase + mmu_ptob(base),
4395 	    mmu_ptob(end - base), base, PROT_READ | PROT_WRITE,
4396 	    HAT_LOAD | HAT_LOAD_LOCK | HAT_LOAD_NOCONSIST);
4397 }
4398 
4399 void
4400 hat_kpm_addmem_mseg_insert(struct memseg *msp)
4401 {
4402 	_NOTE(ARGUNUSED(msp));
4403 }
4404 
4405 void
4406 hat_kpm_addmem_memsegs_update(struct memseg *msp)
4407 {
4408 	_NOTE(ARGUNUSED(msp));
4409 }
4410 
4411 /*
4412  * Return end of metadata for an already setup memseg.
4413  * X86 platforms don't need per-page meta data to support kpm.
4414  */
4415 caddr_t
4416 hat_kpm_mseg_reuse(struct memseg *msp)
4417 {
4418 	return ((caddr_t)msp->epages);
4419 }
4420 
4421 void
4422 hat_kpm_delmem_mseg_update(struct memseg *msp, struct memseg **mspp)
4423 {
4424 	_NOTE(ARGUNUSED(msp, mspp));
4425 	ASSERT(0);
4426 }
4427 
4428 void
4429 hat_kpm_split_mseg_update(struct memseg *msp, struct memseg **mspp,
4430 	struct memseg *lo, struct memseg *mid, struct memseg *hi)
4431 {
4432 	_NOTE(ARGUNUSED(msp, mspp, lo, mid, hi));
4433 	ASSERT(0);
4434 }
4435 
4436 /*
4437  * Walk the memsegs chain, applying func to each memseg span.
4438  */
4439 void
4440 hat_kpm_walk(void (*func)(void *, void *, size_t), void *arg)
4441 {
4442 	pfn_t	pbase, pend;
4443 	void	*base;
4444 	size_t	size;
4445 	struct memseg *msp;
4446 
4447 	for (msp = memsegs; msp; msp = msp->next) {
4448 		pbase = msp->pages_base;
4449 		pend = msp->pages_end;
4450 		base = ptob(pbase) + kpm_vbase;
4451 		size = ptob(pend - pbase);
4452 		func(arg, base, size);
4453 	}
4454 }
4455 
4456 #else	/* __xpv */
4457 
4458 /*
4459  * There are specific Hypervisor calls to establish and remove mappings
4460  * to grant table references and the privcmd driver. We have to ensure
4461  * that a page table actually exists.
4462  */
4463 void
4464 hat_prepare_mapping(hat_t *hat, caddr_t addr, uint64_t *pte_ma)
4465 {
4466 	maddr_t base_ma;
4467 	htable_t *ht;
4468 	uint_t entry;
4469 
4470 	ASSERT(IS_P2ALIGNED((uintptr_t)addr, MMU_PAGESIZE));
4471 	XPV_DISALLOW_MIGRATE();
4472 	ht = htable_create(hat, (uintptr_t)addr, 0, NULL);
4473 
4474 	/*
4475 	 * if an address for pte_ma is passed in, return the MA of the pte
4476 	 * for this specific address.  This address is only valid as long
4477 	 * as the htable stays locked.
4478 	 */
4479 	if (pte_ma != NULL) {
4480 		entry = htable_va2entry((uintptr_t)addr, ht);
4481 		base_ma = pa_to_ma(ptob(ht->ht_pfn));
4482 		*pte_ma = base_ma + (entry << mmu.pte_size_shift);
4483 	}
4484 	XPV_ALLOW_MIGRATE();
4485 }
4486 
4487 void
4488 hat_release_mapping(hat_t *hat, caddr_t addr)
4489 {
4490 	htable_t *ht;
4491 
4492 	ASSERT(IS_P2ALIGNED((uintptr_t)addr, MMU_PAGESIZE));
4493 	XPV_DISALLOW_MIGRATE();
4494 	ht = htable_lookup(hat, (uintptr_t)addr, 0);
4495 	ASSERT(ht != NULL);
4496 	ASSERT(ht->ht_busy >= 2);
4497 	htable_release(ht);
4498 	htable_release(ht);
4499 	XPV_ALLOW_MIGRATE();
4500 }
4501 #endif	/* __xpv */
4502