xref: /freebsd/sys/arm64/arm64/pmap.c (revision 728d9f322935905c09236e8312b3268b6ff8691b)
1 /*-
2  * Copyright (c) 1991 Regents of the University of California.
3  * All rights reserved.
4  * Copyright (c) 1994 John S. Dyson
5  * All rights reserved.
6  * Copyright (c) 1994 David Greenman
7  * All rights reserved.
8  * Copyright (c) 2003 Peter Wemm
9  * All rights reserved.
10  * Copyright (c) 2005-2010 Alan L. Cox <alc@cs.rice.edu>
11  * All rights reserved.
12  * Copyright (c) 2014 Andrew Turner
13  * All rights reserved.
14  * Copyright (c) 2014-2016 The FreeBSD Foundation
15  * All rights reserved.
16  *
17  * This code is derived from software contributed to Berkeley by
18  * the Systems Programming Group of the University of Utah Computer
19  * Science Department and William Jolitz of UUNET Technologies Inc.
20  *
21  * This software was developed by Andrew Turner under sponsorship from
22  * the FreeBSD Foundation.
23  *
24  * Redistribution and use in source and binary forms, with or without
25  * modification, are permitted provided that the following conditions
26  * are met:
27  * 1. Redistributions of source code must retain the above copyright
28  *    notice, this list of conditions and the following disclaimer.
29  * 2. Redistributions in binary form must reproduce the above copyright
30  *    notice, this list of conditions and the following disclaimer in the
31  *    documentation and/or other materials provided with the distribution.
32  * 3. All advertising materials mentioning features or use of this software
33  *    must display the following acknowledgement:
34  *	This product includes software developed by the University of
35  *	California, Berkeley and its contributors.
36  * 4. Neither the name of the University nor the names of its contributors
37  *    may be used to endorse or promote products derived from this software
38  *    without specific prior written permission.
39  *
40  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
41  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
43  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
44  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
45  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
46  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
48  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
49  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
50  * SUCH DAMAGE.
51  */
52 /*-
53  * Copyright (c) 2003 Networks Associates Technology, Inc.
54  * All rights reserved.
55  *
56  * This software was developed for the FreeBSD Project by Jake Burkholder,
57  * Safeport Network Services, and Network Associates Laboratories, the
58  * Security Research Division of Network Associates, Inc. under
59  * DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA
60  * CHATS research program.
61  *
62  * Redistribution and use in source and binary forms, with or without
63  * modification, are permitted provided that the following conditions
64  * are met:
65  * 1. Redistributions of source code must retain the above copyright
66  *    notice, this list of conditions and the following disclaimer.
67  * 2. Redistributions in binary form must reproduce the above copyright
68  *    notice, this list of conditions and the following disclaimer in the
69  *    documentation and/or other materials provided with the distribution.
70  *
71  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
72  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
73  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
74  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
75  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
76  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
77  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
78  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
79  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
80  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
81  * SUCH DAMAGE.
82  */
83 
84 #include <sys/cdefs.h>
85 /*
86  *	Manages physical address maps.
87  *
88  *	Since the information managed by this module is
89  *	also stored by the logical address mapping module,
90  *	this module may throw away valid virtual-to-physical
91  *	mappings at almost any time.  However, invalidations
92  *	of virtual-to-physical mappings must be done as
93  *	requested.
94  *
95  *	In order to cope with hardware architectures which
96  *	make virtual-to-physical map invalidates expensive,
97  *	this module may delay invalidate or reduced protection
98  *	operations until such time as they are actually
99  *	necessary.  This module is given full information as
100  *	to which processors are currently using which maps,
101  *	and to when physical maps must be made correct.
102  */
103 
104 #include "opt_vm.h"
105 
106 #include <sys/param.h>
107 #include <sys/asan.h>
108 #include <sys/bitstring.h>
109 #include <sys/bus.h>
110 #include <sys/systm.h>
111 #include <sys/kernel.h>
112 #include <sys/ktr.h>
113 #include <sys/limits.h>
114 #include <sys/lock.h>
115 #include <sys/malloc.h>
116 #include <sys/mman.h>
117 #include <sys/msan.h>
118 #include <sys/msgbuf.h>
119 #include <sys/mutex.h>
120 #include <sys/physmem.h>
121 #include <sys/proc.h>
122 #include <sys/rangeset.h>
123 #include <sys/rwlock.h>
124 #include <sys/sbuf.h>
125 #include <sys/sx.h>
126 #include <sys/vmem.h>
127 #include <sys/vmmeter.h>
128 #include <sys/sched.h>
129 #include <sys/sysctl.h>
130 #include <sys/_unrhdr.h>
131 #include <sys/smp.h>
132 
133 #include <vm/vm.h>
134 #include <vm/vm_param.h>
135 #include <vm/vm_kern.h>
136 #include <vm/vm_page.h>
137 #include <vm/vm_map.h>
138 #include <vm/vm_object.h>
139 #include <vm/vm_extern.h>
140 #include <vm/vm_pageout.h>
141 #include <vm/vm_pager.h>
142 #include <vm/vm_phys.h>
143 #include <vm/vm_radix.h>
144 #include <vm/vm_reserv.h>
145 #include <vm/vm_dumpset.h>
146 #include <vm/uma.h>
147 
148 #include <machine/asan.h>
149 #include <machine/cpu.h>
150 #include <machine/cpu_feat.h>
151 #include <machine/elf.h>
152 #include <machine/ifunc.h>
153 #include <machine/machdep.h>
154 #include <machine/md_var.h>
155 #include <machine/pcb.h>
156 #include <machine/rsi.h>
157 
158 #ifdef NUMA
159 #define	PMAP_MEMDOM	MAXMEMDOM
160 #else
161 #define	PMAP_MEMDOM	1
162 #endif
163 
164 #define	PMAP_ASSERT_STAGE1(pmap)	MPASS((pmap)->pm_stage == PM_STAGE1)
165 #define	PMAP_ASSERT_STAGE2(pmap)	MPASS((pmap)->pm_stage == PM_STAGE2)
166 
167 #define	NL0PG		(PAGE_SIZE/(sizeof (pd_entry_t)))
168 #define	NL1PG		(PAGE_SIZE/(sizeof (pd_entry_t)))
169 #define	NL2PG		(PAGE_SIZE/(sizeof (pd_entry_t)))
170 #define	NL3PG		(PAGE_SIZE/(sizeof (pt_entry_t)))
171 
172 #define	NUL0E		L0_ENTRIES
173 #define	NUL1E		(NUL0E * NL1PG)
174 #define	NUL2E		(NUL1E * NL2PG)
175 
176 #ifdef PV_STATS
177 #define PV_STAT(x)	do { x ; } while (0)
178 #define __pvused
179 #else
180 #define PV_STAT(x)	do { } while (0)
181 #define __pvused	__unused
182 #endif
183 
184 #define	pmap_l0_pindex(v)	(NUL2E + NUL1E + ((v) >> L0_SHIFT))
185 #define	pmap_l1_pindex(v)	(NUL2E + ((v) >> L1_SHIFT))
186 #define	pmap_l2_pindex(v)	((v) >> L2_SHIFT)
187 
188 #ifdef __ARM_FEATURE_BTI_DEFAULT
189 pt_entry_t __read_mostly pmap_gp_attr;
190 #define	ATTR_KERN_GP		pmap_gp_attr
191 #else
192 #define	ATTR_KERN_GP		0
193 #endif
194 #define	PMAP_SAN_PTE_BITS	(ATTR_AF | ATTR_S1_XN | pmap_sh_attr | \
195   ATTR_KERN_GP | ATTR_S1_IDX(VM_MEMATTR_WRITE_BACK) | ATTR_S1_AP(ATTR_S1_AP_RW))
196 
197 static bool __read_mostly pmap_multiple_tlbi = false;
198 
199 struct pmap_large_md_page {
200 	struct rwlock   pv_lock;
201 	struct md_page  pv_page;
202 	/* Pad to a power of 2, see pmap_init_pv_table(). */
203 	int		pv_pad[2];
204 };
205 
206 __exclusive_cache_line static struct pmap_large_md_page pv_dummy_large;
207 #define pv_dummy pv_dummy_large.pv_page
208 __read_mostly static struct pmap_large_md_page *pv_table;
209 
210 __read_mostly uint64_t prot_ns_shared_pa;
211 
212 static struct pmap_large_md_page *
213 _pa_to_pmdp(vm_paddr_t pa)
214 {
215 	struct vm_phys_seg *seg;
216 
217 	if ((seg = vm_phys_paddr_to_seg(pa)) != NULL)
218 		return ((struct pmap_large_md_page *)seg->md_first +
219 		    pmap_l2_pindex(pa) - pmap_l2_pindex(seg->start));
220 	return (NULL);
221 }
222 
223 static struct pmap_large_md_page *
224 pa_to_pmdp(vm_paddr_t pa)
225 {
226 	struct pmap_large_md_page *pvd;
227 
228 	pvd = _pa_to_pmdp(pa);
229 	if (pvd == NULL)
230 		panic("pa 0x%jx not within vm_phys_segs", (uintmax_t)pa);
231 	return (pvd);
232 }
233 
234 static struct pmap_large_md_page *
235 page_to_pmdp(vm_page_t m)
236 {
237 	struct vm_phys_seg *seg;
238 
239 	seg = &vm_phys_segs[m->segind];
240 	return ((struct pmap_large_md_page *)seg->md_first +
241 	    pmap_l2_pindex(VM_PAGE_TO_PHYS(m)) - pmap_l2_pindex(seg->start));
242 }
243 
244 #define	pa_to_pvh(pa)	(&(pa_to_pmdp(pa)->pv_page))
245 #define	page_to_pvh(m)	(&(page_to_pmdp(m)->pv_page))
246 
247 #define	PHYS_TO_PV_LIST_LOCK(pa)	({			\
248 	struct pmap_large_md_page *_pvd;			\
249 	struct rwlock *_lock;					\
250 	_pvd = _pa_to_pmdp(pa);					\
251 	if (__predict_false(_pvd == NULL))			\
252 		_lock = &pv_dummy_large.pv_lock;		\
253 	else							\
254 		_lock = &(_pvd->pv_lock);			\
255 	_lock;							\
256 })
257 
258 static struct rwlock *
259 VM_PAGE_TO_PV_LIST_LOCK(vm_page_t m)
260 {
261 	if ((m->flags & PG_FICTITIOUS) == 0)
262 		return (&page_to_pmdp(m)->pv_lock);
263 	else
264 		return (&pv_dummy_large.pv_lock);
265 }
266 
267 #define	CHANGE_PV_LIST_LOCK(lockp, new_lock)	do {	\
268 	struct rwlock **_lockp = (lockp);		\
269 	struct rwlock *_new_lock = (new_lock);		\
270 							\
271 	if (_new_lock != *_lockp) {			\
272 		if (*_lockp != NULL)			\
273 			rw_wunlock(*_lockp);		\
274 		*_lockp = _new_lock;			\
275 		rw_wlock(*_lockp);			\
276 	}						\
277 } while (0)
278 
279 #define	CHANGE_PV_LIST_LOCK_TO_PHYS(lockp, pa)		\
280 			CHANGE_PV_LIST_LOCK(lockp, PHYS_TO_PV_LIST_LOCK(pa))
281 
282 #define	CHANGE_PV_LIST_LOCK_TO_VM_PAGE(lockp, m)	\
283 			CHANGE_PV_LIST_LOCK(lockp, VM_PAGE_TO_PV_LIST_LOCK(m))
284 
285 #define	RELEASE_PV_LIST_LOCK(lockp)		do {	\
286 	struct rwlock **_lockp = (lockp);		\
287 							\
288 	if (*_lockp != NULL) {				\
289 		rw_wunlock(*_lockp);			\
290 		*_lockp = NULL;				\
291 	}						\
292 } while (0)
293 
294 #define PTE_TO_VM_PAGE(pte) PHYS_TO_VM_PAGE(PTE_TO_PHYS(pte))
295 #define VM_PAGE_TO_PTE(m) PHYS_TO_PTE(VM_PAGE_TO_PHYS(m))
296 
297 static struct mtx cmap_lock;
298 static void *cmap1_addr;
299 static pt_entry_t *cmap1_pte;
300 
301 /*
302  * The presence of this flag indicates that the mapping is writeable.
303  * If the ATTR_S1_AP_RO bit is also set, then the mapping is clean, otherwise
304  * it is dirty.  This flag may only be set on managed mappings.
305  *
306  * The DBM bit is reserved on ARMv8.0 but it seems we can safely treat it
307  * as a software managed bit.
308  */
309 #define	ATTR_SW_DBM	ATTR_DBM
310 
311 struct pmap kernel_pmap_store;
312 
313 /* Used for mapping ACPI memory before VM is initialized */
314 #define	PMAP_PREINIT_MAPPING_COUNT	32
315 #define	PMAP_PREINIT_MAPPING_SIZE	(PMAP_PREINIT_MAPPING_COUNT * L2_SIZE)
316 static vm_offset_t preinit_map_va;	/* Start VA of pre-init mapping space */
317 static int vm_initialized = 0;		/* No need to use pre-init maps when set */
318 
319 /*
320  * Reserve a few L2 blocks starting from 'preinit_map_va' pointer.
321  * Always map entire L2 block for simplicity.
322  * VA of L2 block = preinit_map_va + i * L2_SIZE
323  */
324 static struct pmap_preinit_mapping {
325 	vm_paddr_t	pa;
326 	void		*va;
327 	vm_size_t	size;
328 } pmap_preinit_mapping[PMAP_PREINIT_MAPPING_COUNT];
329 
330 vm_offset_t virtual_avail;	/* VA of first avail page (after kernel bss) */
331 vm_offset_t virtual_end;	/* VA of last avail page (end of kernel AS) */
332 vm_offset_t kernel_vm_end = 0;
333 
334 /*
335  * Data for the pv entry allocation mechanism.
336  */
337 #ifdef NUMA
338 static __inline int
339 pc_to_domain(struct pv_chunk *pc)
340 {
341 	return (vm_phys_domain(DMAP_TO_PHYS(pc)));
342 }
343 #else
344 static __inline int
345 pc_to_domain(struct pv_chunk *pc __unused)
346 {
347 	return (0);
348 }
349 #endif
350 
351 struct pv_chunks_list {
352 	struct mtx pvc_lock;
353 	TAILQ_HEAD(pch, pv_chunk) pvc_list;
354 	int active_reclaims;
355 } __aligned(CACHE_LINE_SIZE);
356 
357 struct pv_chunks_list __exclusive_cache_line pv_chunks[PMAP_MEMDOM];
358 
359 vm_paddr_t dmap_phys_base;	/* The start of the dmap region */
360 vm_paddr_t dmap_phys_max;	/* The limit of the dmap region */
361 vm_offset_t dmap_max_addr;	/* The virtual address limit of the dmap */
362 static int dmap_attr = VM_MEMATTR_WRITE_BACK;
363 
364 extern pt_entry_t pagetable_l0_ttbr1[];
365 
366 #define	PHYSMAP_SIZE	(2 * (VM_PHYSSEG_MAX - 1))
367 static vm_paddr_t physmap[PHYSMAP_SIZE];
368 static u_int physmap_idx;
369 
370 static SYSCTL_NODE(_vm, OID_AUTO, pmap, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
371     "VM/pmap parameters");
372 
373 static int pmap_growkernel_panic = 0;
374 SYSCTL_INT(_vm_pmap, OID_AUTO, growkernel_panic, CTLFLAG_RDTUN,
375     &pmap_growkernel_panic, 0,
376     "panic on failure to allocate kernel page table page");
377 
378 bool pmap_lpa_enabled __read_mostly = false;
379 pt_entry_t pmap_sh_attr __read_mostly = ATTR_SH(ATTR_SH_IS);
380 
381 #if PAGE_SIZE == PAGE_SIZE_4K
382 #define	L1_BLOCKS_SUPPORTED	1
383 #else
384 #define	L1_BLOCKS_SUPPORTED	(pmap_lpa_enabled)
385 #endif
386 
387 #define	PMAP_ASSERT_L1_BLOCKS_SUPPORTED	MPASS(L1_BLOCKS_SUPPORTED)
388 
389 static bool pmap_l1_supported __read_mostly = false;
390 
391 /*
392  * This ASID allocator uses a bit vector ("asid_set") to remember which ASIDs
393  * that it has currently allocated to a pmap, a cursor ("asid_next") to
394  * optimize its search for a free ASID in the bit vector, and an epoch number
395  * ("asid_epoch") to indicate when it has reclaimed all previously allocated
396  * ASIDs that are not currently active on a processor.
397  *
398  * The current epoch number is always in the range [0, INT_MAX).  Negative
399  * numbers and INT_MAX are reserved for special cases that are described
400  * below.
401  */
402 struct asid_set {
403 	int asid_bits;
404 	bitstr_t *asid_set;
405 	int asid_set_size;
406 	int asid_next;
407 	int asid_epoch;
408 	struct mtx asid_set_mutex;
409 };
410 
411 static struct asid_set asids;
412 static struct asid_set vmids;
413 
414 static SYSCTL_NODE(_vm_pmap, OID_AUTO, asid, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
415     "ASID allocator");
416 SYSCTL_INT(_vm_pmap_asid, OID_AUTO, bits, CTLFLAG_RD, &asids.asid_bits, 0,
417     "The number of bits in an ASID");
418 SYSCTL_INT(_vm_pmap_asid, OID_AUTO, next, CTLFLAG_RD, &asids.asid_next, 0,
419     "The last allocated ASID plus one");
420 SYSCTL_INT(_vm_pmap_asid, OID_AUTO, epoch, CTLFLAG_RD, &asids.asid_epoch, 0,
421     "The current epoch number");
422 
423 static SYSCTL_NODE(_vm_pmap, OID_AUTO, vmid, CTLFLAG_RD, 0, "VMID allocator");
424 SYSCTL_INT(_vm_pmap_vmid, OID_AUTO, bits, CTLFLAG_RD, &vmids.asid_bits, 0,
425     "The number of bits in an VMID");
426 SYSCTL_INT(_vm_pmap_vmid, OID_AUTO, next, CTLFLAG_RD, &vmids.asid_next, 0,
427     "The last allocated VMID plus one");
428 SYSCTL_INT(_vm_pmap_vmid, OID_AUTO, epoch, CTLFLAG_RD, &vmids.asid_epoch, 0,
429     "The current epoch number");
430 
431 void (*pmap_clean_stage2_tlbi)(void);
432 void (*pmap_stage2_invalidate_range)(uint64_t, vm_offset_t, vm_offset_t, bool);
433 void (*pmap_stage2_invalidate_all)(uint64_t);
434 
435 /*
436  * A pmap's cookie encodes an ASID and epoch number.  Cookies for reserved
437  * ASIDs have a negative epoch number, specifically, INT_MIN.  Cookies for
438  * dynamically allocated ASIDs have a non-negative epoch number.
439  *
440  * An invalid ASID is represented by -1.
441  *
442  * There are two special-case cookie values: (1) COOKIE_FROM(-1, INT_MIN),
443  * which indicates that an ASID should never be allocated to the pmap, and
444  * (2) COOKIE_FROM(-1, INT_MAX), which indicates that an ASID should be
445  * allocated when the pmap is next activated.
446  */
447 #define	COOKIE_FROM(asid, epoch)	((long)((u_int)(asid) |	\
448 					    ((u_long)(epoch) << 32)))
449 #define	COOKIE_TO_ASID(cookie)		((int)(cookie))
450 #define	COOKIE_TO_EPOCH(cookie)		((int)((u_long)(cookie) >> 32))
451 
452 #define	TLBI_VA_SHIFT			12
453 #define	TLBI_VA_MASK			((1ul << 44) - 1)
454 #define	TLBI_VA(addr)			(((addr) >> TLBI_VA_SHIFT) & TLBI_VA_MASK)
455 
456 /*
457  * The operand to a range-based TLBI instruction has the following fields:
458  *
459  *   63      48 47   46 45    44 43    39 38    37 36              0
460  *  +----------+-------+--------+--------+--------+-----------------+
461  *  |   ASID   |  TG   | SCALE  |  NUM   |  TTL   |    BaseADDR     |
462  *  +----------+-------+--------+--------+--------+-----------------+
463  *
464  * A single range-based TLBI instruction invalidates the TLB entries for the
465  * mappings within the address range
466  *
467  *	[BaseADDR, BaseADDR + (NUM + 1) * 2^(5 * SCALE + 1) * PAGE_SIZE)
468  *
469  * BaseADDR is VA[48:PAGE_SHIFT], unless 52-bit addressing is enabled, i.e.,
470  * pmap_lpa_enabled is true, in which case BaseADDR is VA[52:16] regardless
471  * of the page size.  Consequently, when pmap_lpa_enabled is true, the start
472  * of the address range must be 64KB aligned, and any leading pages must be
473  * invalidated individually.
474  *
475  * TTL optionally specifies the translation table level at which every
476  * mapping within the address range can be found; we currently set TTL to 0,
477  * meaning that we are not providing a hint.
478  *
479  * A single instruction invalidates some number of units, where a unit is
480  * 2^(5 * SCALE + 1) pages.  NUM is that number minus 1.
481  *
482  * TG specifies the translation granule size, i.e., PAGE_SIZE.
483  */
484 #define	TLBI_RANGE_VA_SHIFT()		(pmap_lpa_enabled ? 16 : PAGE_SHIFT)
485 
486 #define	TLBI_RANGE_BADDR_MASK		((1ul << 37) - 1)
487 #define	TLBI_RANGE_NUM_SHIFT		39
488 #define	TLBI_RANGE_SCALE_SHIFT		44
489 #define	TLBI_RANGE_TG_SHIFT		46
490 
491 #define	TLBI_RANGE_MAX_UNITS		32
492 #define	TLBI_RANGE_MAX_SCALE		3
493 
494 #define	TLBI_RANGE_UNIT_SHIFT(scale)	(5 * (scale) + 1)
495 #define	TLBI_RANGE_UNIT(scale)		(1ul << TLBI_RANGE_UNIT_SHIFT(scale))
496 
497 /*
498  * The largest scale such that a unit fits within the given number of pages,
499  * i.e., the largest scale such that TLBI_RANGE_UNIT(scale) <= pages.  The
500  * given number of pages must be at least TLBI_RANGE_UNIT(0).
501  */
502 #define	TLBI_RANGE_SCALE(pages)						\
503 	imin((flsl(pages) - 2) / 5, TLBI_RANGE_MAX_SCALE)
504 
505 #if PAGE_SIZE == PAGE_SIZE_4K
506 #define	TLBI_RANGE_TG			(1ul << TLBI_RANGE_TG_SHIFT)
507 #elif PAGE_SIZE == PAGE_SIZE_16K
508 #define	TLBI_RANGE_TG			(2ul << TLBI_RANGE_TG_SHIFT)
509 #else
510 #error Unsupported page size
511 #endif
512 
513 #define	TLBI_RANGE_FIELDS(va, va_shift, num, scale)			\
514 	(TLBI_RANGE_TG | ((u_long)(scale) << TLBI_RANGE_SCALE_SHIFT) |	\
515 	((u_long)(num) << TLBI_RANGE_NUM_SHIFT) |			\
516 	(((va) >> (va_shift)) & TLBI_RANGE_BADDR_MASK))
517 
518 static bool __read_frequently pmap_tlbi_range_support = false;
519 
520 static int __read_frequently superpages_enabled = 1;
521 SYSCTL_INT(_vm_pmap, OID_AUTO, superpages_enabled,
522     CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &superpages_enabled, 0,
523     "Are large page mappings enabled?");
524 
525 /*
526  * True when Branch Target Identification should be used by userspace. This
527  * allows pmap to mark pages as guarded with ATTR_S1_GP.
528  */
529 __read_mostly static bool pmap_bti_support = false;
530 
531 /*
532  * Internal flags for pmap_enter()'s helper functions.
533  */
534 #define	PMAP_ENTER_NORECLAIM	0x1000000	/* Don't reclaim PV entries. */
535 #define	PMAP_ENTER_NOREPLACE	0x2000000	/* Don't replace mappings. */
536 
537 TAILQ_HEAD(pv_chunklist, pv_chunk);
538 
539 static void	free_pv_chunk(struct pv_chunk *pc);
540 static void	free_pv_chunk_batch(struct pv_chunklist *batch);
541 static void	free_pv_entry(pmap_t pmap, pv_entry_t pv);
542 static pv_entry_t get_pv_entry(pmap_t pmap, struct rwlock **lockp);
543 static vm_page_t reclaim_pv_chunk(pmap_t locked_pmap, struct rwlock **lockp);
544 static void	pmap_pvh_free(struct md_page *pvh, pmap_t pmap, vm_offset_t va);
545 static pv_entry_t pmap_pvh_remove(struct md_page *pvh, pmap_t pmap,
546 		    vm_offset_t va);
547 
548 static void pmap_abort_ptp(pmap_t pmap, vm_offset_t va, vm_page_t mpte);
549 static bool pmap_activate_int(struct thread *td, pmap_t pmap);
550 static void pmap_alloc_asid(pmap_t pmap);
551 static int pmap_change_props_locked(void *addr, vm_size_t size,
552     vm_prot_t prot, int mode, int old_mode, bool skip_unmapped);
553 static bool pmap_copy_l3c(pmap_t pmap, pt_entry_t *l3p, vm_offset_t va,
554     pt_entry_t l3e, vm_page_t ml3, struct rwlock **lockp);
555 static pt_entry_t *pmap_demote_l1(pmap_t pmap, pt_entry_t *l1, vm_offset_t va);
556 static pt_entry_t *pmap_demote_l2_locked(pmap_t pmap, pt_entry_t *l2,
557     vm_offset_t va, struct rwlock **lockp);
558 static pt_entry_t *pmap_demote_l2(pmap_t pmap, pt_entry_t *l2, vm_offset_t va);
559 static bool pmap_demote_l2c(pmap_t pmap, pt_entry_t *l2p, vm_offset_t va);
560 static bool pmap_demote_l3c(pmap_t pmap, pt_entry_t *l3p, vm_offset_t va);
561 static vm_page_t pmap_enter_quick_locked(pmap_t pmap, vm_offset_t va,
562     vm_page_t m, vm_prot_t prot, vm_page_t mpte, struct rwlock **lockp);
563 static int pmap_enter_l2(pmap_t pmap, vm_offset_t va, pd_entry_t new_l2,
564     u_int flags, vm_page_t m, struct rwlock **lockp);
565 static int pmap_enter_l3c(pmap_t pmap, vm_offset_t va, pt_entry_t l3e, u_int flags,
566     vm_page_t m, vm_page_t *ml3p, struct rwlock **lockp);
567 static bool pmap_every_pte_zero(vm_paddr_t pa);
568 static int pmap_insert_pt_page(pmap_t pmap, vm_page_t mpte, bool promoted,
569     bool all_l3e_AF_set);
570 static pt_entry_t pmap_load_l3c(pt_entry_t *l3p);
571 static void pmap_mask_set_l3c(pmap_t pmap, pt_entry_t *l3p, vm_offset_t va,
572     vm_offset_t *vap, vm_offset_t va_next, pt_entry_t mask, pt_entry_t nbits);
573 static bool pmap_page_is_mapped_locked(vm_page_t m);
574 static bool pmap_pv_insert_l3c(pmap_t pmap, vm_offset_t va, vm_page_t m,
575     struct rwlock **lockp);
576 static void pmap_remove_kernel_l2(pmap_t pmap, pt_entry_t *l2, vm_offset_t va);
577 static int pmap_remove_l2(pmap_t pmap, pt_entry_t *l2, vm_offset_t sva,
578     pd_entry_t l1e, bool demote_kl2e, struct spglist *free,
579     struct rwlock **lockp);
580 static int pmap_remove_l3(pmap_t pmap, pt_entry_t *l3, vm_offset_t sva,
581     pd_entry_t l2e, struct spglist *free, struct rwlock **lockp);
582 static bool pmap_remove_l3c(pmap_t pmap, pt_entry_t *l3p, vm_offset_t va,
583     vm_offset_t *vap, vm_offset_t va_next, vm_page_t ml3, struct spglist *free,
584     struct rwlock **lockp);
585 static void pmap_reset_asid_set(pmap_t pmap);
586 static bool pmap_try_insert_pv_entry(pmap_t pmap, vm_offset_t va,
587     vm_page_t m, struct rwlock **lockp);
588 
589 static vm_page_t _pmap_alloc_l3(pmap_t pmap, vm_pindex_t ptepindex,
590 		struct rwlock **lockp);
591 
592 static void _pmap_unwire_l3(pmap_t pmap, vm_offset_t va, vm_page_t m,
593     struct spglist *free);
594 static int pmap_unuse_pt(pmap_t, vm_offset_t, pd_entry_t, struct spglist *);
595 static void pmap_update_entry(pmap_t pmap, pd_entry_t *pte, pd_entry_t newpte,
596     vm_offset_t va, vm_size_t size, bool final_only);
597 static __inline vm_page_t pmap_remove_pt_page(pmap_t pmap, vm_offset_t va);
598 
599 static uma_zone_t pmap_bti_ranges_zone;
600 static bool pmap_bti_same(pmap_t pmap, vm_offset_t sva, vm_offset_t eva,
601     pt_entry_t *pte);
602 static pt_entry_t pmap_pte_bti(pmap_t pmap, vm_offset_t va);
603 static void pmap_bti_on_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva);
604 static void *bti_dup_range(void *ctx, void *data);
605 static void bti_free_range(void *ctx, void *node);
606 static int pmap_bti_copy(pmap_t dst_pmap, pmap_t src_pmap);
607 static void pmap_bti_deassign_all(pmap_t pmap);
608 static void pagezero(void *);
609 
610 static void pmap_set_protected(pt_entry_t old_l3);
611 static void pmap_set_unprotected(pt_entry_t new_l3);
612 
613 /*
614  * These load the old table data and store the new value.
615  * They need to be atomic as the System MMU may write to the table at
616  * the same time as the CPU.
617  */
618 #define	pmap_clear(table)		atomic_store_64(table, 0)
619 #define	pmap_clear_bits(table, bits)	atomic_clear_64(table, bits)
620 #define	pmap_load(table)		(*table)
621 #define	pmap_load_clear(table)		atomic_swap_64(table, 0)
622 #define	pmap_load_store(table, entry)	atomic_swap_64(table, entry)
623 #define	pmap_set_bits(table, bits)	atomic_set_64(table, bits)
624 #define	pmap_store(table, entry)	atomic_store_64(table, entry)
625 
626 /********************/
627 /* Inline functions */
628 /********************/
629 
630 static __inline void
631 pagecopy(void *s, void *d)
632 {
633 
634 	memcpy(d, s, PAGE_SIZE);
635 }
636 
637 static __inline pd_entry_t *
638 pmap_l0(pmap_t pmap, vm_offset_t va)
639 {
640 
641 	return (&pmap->pm_l0[pmap_l0_index(va)]);
642 }
643 
644 static __inline pd_entry_t *
645 pmap_l0_to_l1(pd_entry_t *l0, vm_offset_t va)
646 {
647 	pd_entry_t *l1;
648 
649 	l1 = PHYS_TO_DMAP(PTE_TO_PHYS(pmap_load(l0)));
650 	return (&l1[pmap_l1_index(va)]);
651 }
652 
653 static __inline pd_entry_t *
654 pmap_l1(pmap_t pmap, vm_offset_t va)
655 {
656 	pd_entry_t *l0;
657 
658 	l0 = pmap_l0(pmap, va);
659 	if ((pmap_load(l0) & ATTR_DESCR_MASK) != L0_TABLE)
660 		return (NULL);
661 
662 	return (pmap_l0_to_l1(l0, va));
663 }
664 
665 static __inline pd_entry_t *
666 pmap_l1_to_l2(pd_entry_t *l1p, vm_offset_t va)
667 {
668 	pd_entry_t l1, *l2p;
669 
670 	l1 = pmap_load(l1p);
671 
672 	KASSERT(ADDR_IS_CANONICAL(va),
673 	    ("%s: Address not in canonical form: %lx", __func__, va));
674 	/*
675 	 * The valid bit may be clear if pmap_update_entry() is concurrently
676 	 * modifying the entry, so for KVA only the entry type may be checked.
677 	 */
678 	KASSERT(ADDR_IS_KERNEL(va) || (l1 & ATTR_DESCR_VALID) != 0,
679 	    ("%s: L1 entry %#lx for %#lx is invalid", __func__, l1, va));
680 	KASSERT((l1 & ATTR_DESCR_TYPE_MASK) == ATTR_DESCR_TYPE_TABLE,
681 	    ("%s: L1 entry %#lx for %#lx is a leaf", __func__, l1, va));
682 	l2p = PHYS_TO_DMAP(PTE_TO_PHYS(l1));
683 	return (&l2p[pmap_l2_index(va)]);
684 }
685 
686 static __inline pd_entry_t *
687 pmap_l2(pmap_t pmap, vm_offset_t va)
688 {
689 	pd_entry_t *l1;
690 
691 	l1 = pmap_l1(pmap, va);
692 	if ((pmap_load(l1) & ATTR_DESCR_MASK) != L1_TABLE)
693 		return (NULL);
694 
695 	return (pmap_l1_to_l2(l1, va));
696 }
697 
698 static __inline pt_entry_t *
699 pmap_l2_to_l3(pd_entry_t *l2p, vm_offset_t va)
700 {
701 	pd_entry_t l2;
702 	pt_entry_t *l3p;
703 
704 	l2 = pmap_load(l2p);
705 
706 	KASSERT(ADDR_IS_CANONICAL(va),
707 	    ("%s: Address not in canonical form: %lx", __func__, va));
708 	/*
709 	 * The valid bit may be clear if pmap_update_entry() is concurrently
710 	 * modifying the entry, so for KVA only the entry type may be checked.
711 	 */
712 	KASSERT(ADDR_IS_KERNEL(va) || (l2 & ATTR_DESCR_VALID) != 0,
713 	    ("%s: L2 entry %#lx for %#lx is invalid", __func__, l2, va));
714 	KASSERT((l2 & ATTR_DESCR_TYPE_MASK) == ATTR_DESCR_TYPE_TABLE,
715 	    ("%s: L2 entry %#lx for %#lx is a leaf", __func__, l2, va));
716 	l3p = PHYS_TO_DMAP(PTE_TO_PHYS(l2));
717 	return (&l3p[pmap_l3_index(va)]);
718 }
719 
720 /*
721  * Returns the lowest valid pde for a given virtual address.
722  * The next level may or may not point to a valid page or block.
723  */
724 static __inline pd_entry_t *
725 pmap_pde(pmap_t pmap, vm_offset_t va, int *level)
726 {
727 	pd_entry_t *l0, *l1, *l2, desc;
728 
729 	l0 = pmap_l0(pmap, va);
730 	desc = pmap_load(l0) & ATTR_DESCR_MASK;
731 	if (desc != L0_TABLE) {
732 		*level = -1;
733 		return (NULL);
734 	}
735 
736 	l1 = pmap_l0_to_l1(l0, va);
737 	desc = pmap_load(l1) & ATTR_DESCR_MASK;
738 	if (desc != L1_TABLE) {
739 		*level = 0;
740 		return (l0);
741 	}
742 
743 	l2 = pmap_l1_to_l2(l1, va);
744 	desc = pmap_load(l2) & ATTR_DESCR_MASK;
745 	if (desc != L2_TABLE) {
746 		*level = 1;
747 		return (l1);
748 	}
749 
750 	*level = 2;
751 	return (l2);
752 }
753 
754 /*
755  * Returns the lowest valid pte block or table entry for a given virtual
756  * address. If there are no valid entries return NULL and set the level to
757  * the first invalid level.
758  */
759 static __inline pt_entry_t *
760 pmap_pte(pmap_t pmap, vm_offset_t va, int *level)
761 {
762 	pd_entry_t *l1, *l2, desc;
763 	pt_entry_t *l3;
764 
765 	l1 = pmap_l1(pmap, va);
766 	if (l1 == NULL) {
767 		*level = 0;
768 		return (NULL);
769 	}
770 	desc = pmap_load(l1) & ATTR_DESCR_MASK;
771 	if (desc == L1_BLOCK) {
772 		PMAP_ASSERT_L1_BLOCKS_SUPPORTED;
773 		*level = 1;
774 		return (l1);
775 	}
776 
777 	if (desc != L1_TABLE) {
778 		*level = 1;
779 		return (NULL);
780 	}
781 
782 	l2 = pmap_l1_to_l2(l1, va);
783 	desc = pmap_load(l2) & ATTR_DESCR_MASK;
784 	if (desc == L2_BLOCK) {
785 		*level = 2;
786 		return (l2);
787 	}
788 
789 	if (desc != L2_TABLE) {
790 		*level = 2;
791 		return (NULL);
792 	}
793 
794 	*level = 3;
795 	l3 = pmap_l2_to_l3(l2, va);
796 	if ((pmap_load(l3) & ATTR_DESCR_MASK) != L3_PAGE)
797 		return (NULL);
798 
799 	return (l3);
800 }
801 
802 /*
803  * If the given pmap has an L{1,2}_BLOCK or L3_PAGE entry at the specified
804  * level that maps the specified virtual address, then a pointer to that entry
805  * is returned.  Otherwise, NULL is returned, unless INVARIANTS are enabled
806  * and a diagnostic message is provided, in which case this function panics.
807  */
808 static __always_inline pt_entry_t *
809 pmap_pte_exists(pmap_t pmap, vm_offset_t va, int level, const char *diag)
810 {
811 	pd_entry_t *l0p, *l1p, *l2p;
812 	pt_entry_t desc, *l3p;
813 	int walk_level __diagused;
814 
815 	KASSERT(level >= 0 && level < 4,
816 	    ("%s: %s passed an out-of-range level (%d)", __func__, diag,
817 	    level));
818 	l0p = pmap_l0(pmap, va);
819 	desc = pmap_load(l0p) & ATTR_DESCR_MASK;
820 	if (desc == L0_TABLE && level > 0) {
821 		l1p = pmap_l0_to_l1(l0p, va);
822 		desc = pmap_load(l1p) & ATTR_DESCR_MASK;
823 		if (desc == L1_BLOCK && level == 1) {
824 			PMAP_ASSERT_L1_BLOCKS_SUPPORTED;
825 			return (l1p);
826 		}
827 		if (desc == L1_TABLE && level > 1) {
828 			l2p = pmap_l1_to_l2(l1p, va);
829 			desc = pmap_load(l2p) & ATTR_DESCR_MASK;
830 			if (desc == L2_BLOCK && level == 2)
831 				return (l2p);
832 			else if (desc == L2_TABLE && level > 2) {
833 				l3p = pmap_l2_to_l3(l2p, va);
834 				desc = pmap_load(l3p) & ATTR_DESCR_MASK;
835 				if (desc == L3_PAGE && level == 3)
836 					return (l3p);
837 				else
838 					walk_level = 3;
839 			} else
840 				walk_level = 2;
841 		} else
842 			walk_level = 1;
843 	} else
844 		walk_level = 0;
845 	KASSERT(diag == NULL,
846 	    ("%s: va %#lx not mapped at level %d, desc %ld at level %d",
847 	    diag, va, level, desc, walk_level));
848 	return (NULL);
849 }
850 
851 bool
852 pmap_ps_enabled(pmap_t pmap)
853 {
854 	/*
855 	 * Promotion requires a hypervisor call when the kernel is running
856 	 * in EL1. To stop this disable superpage support on non-stage 1
857 	 * pmaps for now.
858 	 */
859 	if (pmap->pm_stage != PM_STAGE1)
860 		return (false);
861 
862 #ifdef KMSAN
863 	/*
864 	 * The break-before-make in pmap_update_entry() results in a situation
865 	 * where a CPU may call into the KMSAN runtime while the entry is
866 	 * invalid.  If the entry is used to map the current thread structure,
867 	 * then the runtime will attempt to access unmapped memory.  Avoid this
868 	 * by simply disabling superpage promotion for the kernel map.
869 	 */
870 	if (pmap == kernel_pmap)
871 		return (false);
872 #endif
873 
874 	return (superpages_enabled != 0);
875 }
876 
877 bool
878 pmap_vs_enabled(void)
879 {
880 	/*
881 	 * 8 and 16 are the only values hardware can support, but allow for the
882 	 * possibility of artificially restricting the bits, e.g. for testing.
883 	 */
884 	KASSERT(vmids.asid_bits <= 16, ("VMID bits %d > 16", vmids.asid_bits));
885 	return (vmids.asid_bits > 8);
886 }
887 
888 bool
889 pmap_get_tables(pmap_t pmap, vm_offset_t va, pd_entry_t **l0, pd_entry_t **l1,
890     pd_entry_t **l2, pt_entry_t **l3)
891 {
892 	pd_entry_t *l0p, *l1p, *l2p;
893 
894 	if (pmap->pm_l0 == NULL)
895 		return (false);
896 
897 	l0p = pmap_l0(pmap, va);
898 	*l0 = l0p;
899 
900 	if ((pmap_load(l0p) & ATTR_DESCR_MASK) != L0_TABLE)
901 		return (false);
902 
903 	l1p = pmap_l0_to_l1(l0p, va);
904 	*l1 = l1p;
905 
906 	if ((pmap_load(l1p) & ATTR_DESCR_MASK) == L1_BLOCK) {
907 		PMAP_ASSERT_L1_BLOCKS_SUPPORTED;
908 		*l2 = NULL;
909 		*l3 = NULL;
910 		return (true);
911 	}
912 
913 	if ((pmap_load(l1p) & ATTR_DESCR_MASK) != L1_TABLE)
914 		return (false);
915 
916 	l2p = pmap_l1_to_l2(l1p, va);
917 	*l2 = l2p;
918 
919 	if ((pmap_load(l2p) & ATTR_DESCR_MASK) == L2_BLOCK) {
920 		*l3 = NULL;
921 		return (true);
922 	}
923 
924 	if ((pmap_load(l2p) & ATTR_DESCR_MASK) != L2_TABLE)
925 		return (false);
926 
927 	*l3 = pmap_l2_to_l3(l2p, va);
928 
929 	return (true);
930 }
931 
932 static __inline int
933 pmap_l3_valid(pt_entry_t l3)
934 {
935 
936 	return ((l3 & ATTR_DESCR_MASK) == L3_PAGE);
937 }
938 
939 CTASSERT(L1_BLOCK == L2_BLOCK);
940 
941 static pt_entry_t
942 pmap_pte_memattr(pmap_t pmap, vm_memattr_t memattr)
943 {
944 	pt_entry_t val;
945 
946 	if (pmap->pm_stage == PM_STAGE1) {
947 		val = ATTR_S1_IDX(memattr);
948 		if (memattr == VM_MEMATTR_DEVICE)
949 			val |= ATTR_S1_XN;
950 		return (val);
951 	}
952 
953 	val = 0;
954 
955 	switch (memattr) {
956 	case VM_MEMATTR_DEVICE:
957 		return (ATTR_S2_MEMATTR(ATTR_S2_MEMATTR_DEVICE_nGnRnE) |
958 		    ATTR_S2_XN(ATTR_S2_XN_ALL));
959 	case VM_MEMATTR_UNCACHEABLE:
960 		return (ATTR_S2_MEMATTR(ATTR_S2_MEMATTR_NC));
961 	case VM_MEMATTR_WRITE_BACK:
962 		return (ATTR_S2_MEMATTR(ATTR_S2_MEMATTR_WB));
963 	case VM_MEMATTR_WRITE_THROUGH:
964 		return (ATTR_S2_MEMATTR(ATTR_S2_MEMATTR_WT));
965 	default:
966 		panic("%s: invalid memory attribute %x", __func__, memattr);
967 	}
968 }
969 
970 static pt_entry_t
971 pmap_pte_prot(pmap_t pmap, vm_prot_t prot)
972 {
973 	pt_entry_t val;
974 
975 	val = 0;
976 	if (pmap->pm_stage == PM_STAGE1) {
977 		if ((prot & VM_PROT_EXECUTE) == 0)
978 			val |= ATTR_S1_XN;
979 		if ((prot & VM_PROT_WRITE) == 0)
980 			val |= ATTR_S1_AP(ATTR_S1_AP_RO);
981 	} else {
982 		if ((prot & VM_PROT_WRITE) != 0)
983 			val |= ATTR_S2_S2AP(ATTR_S2_S2AP_WRITE);
984 		if ((prot & VM_PROT_READ) != 0)
985 			val |= ATTR_S2_S2AP(ATTR_S2_S2AP_READ);
986 		if ((prot & VM_PROT_EXECUTE) == 0)
987 			val |= ATTR_S2_XN(ATTR_S2_XN_ALL);
988 	}
989 
990 	return (val);
991 }
992 
993 /*
994  * Checks if the PTE is dirty.
995  */
996 static inline int
997 pmap_pte_dirty(pmap_t pmap, pt_entry_t pte)
998 {
999 
1000 	KASSERT((pte & ATTR_SW_MANAGED) != 0, ("pte %#lx is unmanaged", pte));
1001 
1002 	if (pmap->pm_stage == PM_STAGE1) {
1003 		KASSERT((pte & (ATTR_S1_AP_RW_BIT | ATTR_SW_DBM)) != 0,
1004 		    ("pte %#lx is writeable and missing ATTR_SW_DBM", pte));
1005 
1006 		return ((pte & (ATTR_S1_AP_RW_BIT | ATTR_SW_DBM)) ==
1007 		    (ATTR_S1_AP(ATTR_S1_AP_RW) | ATTR_SW_DBM));
1008 	}
1009 
1010 	return ((pte & ATTR_S2_S2AP(ATTR_S2_S2AP_WRITE)) ==
1011 	    ATTR_S2_S2AP(ATTR_S2_S2AP_WRITE));
1012 }
1013 
1014 static __inline void
1015 pmap_resident_count_inc(pmap_t pmap, int count)
1016 {
1017 
1018 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
1019 	pmap->pm_stats.resident_count += count;
1020 }
1021 
1022 static __inline void
1023 pmap_resident_count_dec(pmap_t pmap, int count)
1024 {
1025 
1026 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
1027 	KASSERT(pmap->pm_stats.resident_count >= count,
1028 	    ("pmap %p resident count underflow %ld %d", pmap,
1029 	    pmap->pm_stats.resident_count, count));
1030 	pmap->pm_stats.resident_count -= count;
1031 }
1032 
1033 static vm_paddr_t
1034 pmap_early_vtophys(vm_offset_t va)
1035 {
1036 	vm_paddr_t pa_page;
1037 
1038 	pa_page = arm64_address_translate_s1e1r(va) & PAR_PA_MASK;
1039 	return (pa_page | (va & PAR_LOW_MASK));
1040 }
1041 
1042 /* State of the bootstrapped DMAP page tables */
1043 struct pmap_bootstrap_state {
1044 	pt_entry_t	*l1;
1045 	pt_entry_t	*l2;
1046 	pt_entry_t	*l3;
1047 	vm_offset_t	freemempos;
1048 	vm_offset_t	va;
1049 	vm_paddr_t	pa;
1050 	pt_entry_t	table_attrs;
1051 	u_int		l0_slot;
1052 	u_int		l1_slot;
1053 	u_int		l2_slot;
1054 	bool		dmap_valid;
1055 };
1056 
1057 /* The bootstrap state */
1058 static struct pmap_bootstrap_state bs_state = {
1059 	.l1 = NULL,
1060 	.l2 = NULL,
1061 	.l3 = NULL,
1062 	.table_attrs = TATTR_PXN_TABLE,
1063 	.l0_slot = L0_ENTRIES,
1064 	.l1_slot = Ln_ENTRIES,
1065 	.l2_slot = Ln_ENTRIES,
1066 	.dmap_valid = false,
1067 };
1068 
1069 static void
1070 pmap_bootstrap_l0_table(struct pmap_bootstrap_state *state)
1071 {
1072 	vm_paddr_t l1_pa;
1073 	pd_entry_t l0e;
1074 	u_int l0_slot;
1075 
1076 	/* Link the level 0 table to a level 1 table */
1077 	l0_slot = pmap_l0_index(state->va);
1078 	if (l0_slot != state->l0_slot) {
1079 		/*
1080 		 * Make sure we move from a low address to high address
1081 		 * before the DMAP region is ready. This ensures we never
1082 		 * modify an existing mapping until we can map from a
1083 		 * physical address to a virtual address.
1084 		 */
1085 		MPASS(state->l0_slot < l0_slot ||
1086 		    state->l0_slot == L0_ENTRIES ||
1087 		    state->dmap_valid);
1088 
1089 		/* Reset lower levels */
1090 		state->l2 = NULL;
1091 		state->l3 = NULL;
1092 		state->l1_slot = Ln_ENTRIES;
1093 		state->l2_slot = Ln_ENTRIES;
1094 
1095 		/* Check the existing L0 entry */
1096 		state->l0_slot = l0_slot;
1097 		if (state->dmap_valid) {
1098 			l0e = pagetable_l0_ttbr1[l0_slot];
1099 			if ((l0e & ATTR_DESCR_VALID) != 0) {
1100 				MPASS((l0e & ATTR_DESCR_MASK) == L0_TABLE);
1101 				l1_pa = PTE_TO_PHYS(l0e);
1102 				state->l1 = PHYS_TO_DMAP(l1_pa);
1103 				return;
1104 			}
1105 		}
1106 
1107 		/* Create a new L0 table entry */
1108 		state->l1 = (pt_entry_t *)state->freemempos;
1109 		memset_early(state->l1, 0, PAGE_SIZE);
1110 		state->freemempos += PAGE_SIZE;
1111 
1112 		l1_pa = pmap_early_vtophys((vm_offset_t)state->l1);
1113 		MPASS((l1_pa & Ln_TABLE_MASK) == 0);
1114 		MPASS(pagetable_l0_ttbr1[l0_slot] == 0);
1115 		pmap_store(&pagetable_l0_ttbr1[l0_slot], PHYS_TO_PTE(l1_pa) |
1116 		    TATTR_UXN_TABLE | TATTR_AP_TABLE_NO_EL0 | L0_TABLE);
1117 	}
1118 	KASSERT(state->l1 != NULL, ("%s: NULL l1", __func__));
1119 }
1120 
1121 static void
1122 pmap_bootstrap_l1_table(struct pmap_bootstrap_state *state)
1123 {
1124 	vm_paddr_t l2_pa;
1125 	pd_entry_t l1e;
1126 	u_int l1_slot;
1127 
1128 	/* Make sure there is a valid L0 -> L1 table */
1129 	pmap_bootstrap_l0_table(state);
1130 
1131 	/* Link the level 1 table to a level 2 table */
1132 	l1_slot = pmap_l1_index(state->va);
1133 	if (l1_slot != state->l1_slot) {
1134 		/* See pmap_bootstrap_l0_table for a description */
1135 		MPASS(state->l1_slot < l1_slot ||
1136 		    state->l1_slot == Ln_ENTRIES ||
1137 		    state->dmap_valid);
1138 
1139 		/* Reset lower levels */
1140 		state->l3 = NULL;
1141 		state->l2_slot = Ln_ENTRIES;
1142 
1143 		/* Check the existing L1 entry */
1144 		state->l1_slot = l1_slot;
1145 		if (state->dmap_valid) {
1146 			l1e = state->l1[l1_slot];
1147 			if ((l1e & ATTR_DESCR_VALID) != 0) {
1148 				MPASS((l1e & ATTR_DESCR_MASK) == L1_TABLE);
1149 				l2_pa = PTE_TO_PHYS(l1e);
1150 				state->l2 = PHYS_TO_DMAP(l2_pa);
1151 				return;
1152 			}
1153 		}
1154 
1155 		/* Create a new L1 table entry */
1156 		state->l2 = (pt_entry_t *)state->freemempos;
1157 		memset_early(state->l2, 0, PAGE_SIZE);
1158 		state->freemempos += PAGE_SIZE;
1159 
1160 		l2_pa = pmap_early_vtophys((vm_offset_t)state->l2);
1161 		MPASS((l2_pa & Ln_TABLE_MASK) == 0);
1162 		MPASS(state->l1[l1_slot] == 0);
1163 		pmap_store(&state->l1[l1_slot], PHYS_TO_PTE(l2_pa) |
1164 		    state->table_attrs | L1_TABLE);
1165 	}
1166 	KASSERT(state->l2 != NULL, ("%s: NULL l2", __func__));
1167 }
1168 
1169 static void
1170 pmap_bootstrap_l2_table(struct pmap_bootstrap_state *state)
1171 {
1172 	vm_paddr_t l3_pa;
1173 	pd_entry_t l2e;
1174 	u_int l2_slot;
1175 
1176 	/* Make sure there is a valid L1 -> L2 table */
1177 	pmap_bootstrap_l1_table(state);
1178 
1179 	/* Link the level 2 table to a level 3 table */
1180 	l2_slot = pmap_l2_index(state->va);
1181 	if (l2_slot != state->l2_slot) {
1182 		/* See pmap_bootstrap_l0_table for a description */
1183 		MPASS(state->l2_slot < l2_slot ||
1184 		    state->l2_slot == Ln_ENTRIES ||
1185 		    state->dmap_valid);
1186 
1187 		/* Check the existing L2 entry */
1188 		state->l2_slot = l2_slot;
1189 		if (state->dmap_valid) {
1190 			l2e = state->l2[l2_slot];
1191 			if ((l2e & ATTR_DESCR_VALID) != 0) {
1192 				MPASS((l2e & ATTR_DESCR_MASK) == L2_TABLE);
1193 				l3_pa = PTE_TO_PHYS(l2e);
1194 				state->l3 = PHYS_TO_DMAP(l3_pa);
1195 				return;
1196 			}
1197 		}
1198 
1199 		/* Create a new L2 table entry */
1200 		state->l3 = (pt_entry_t *)state->freemempos;
1201 		memset_early(state->l3, 0, PAGE_SIZE);
1202 		state->freemempos += PAGE_SIZE;
1203 
1204 		l3_pa = pmap_early_vtophys((vm_offset_t)state->l3);
1205 		MPASS((l3_pa & Ln_TABLE_MASK) == 0);
1206 		MPASS(state->l2[l2_slot] == 0);
1207 		pmap_store(&state->l2[l2_slot], PHYS_TO_PTE(l3_pa) |
1208 		    state->table_attrs | L2_TABLE);
1209 	}
1210 	KASSERT(state->l3 != NULL, ("%s: NULL l3", __func__));
1211 }
1212 
1213 static void
1214 pmap_bootstrap_l2_block(struct pmap_bootstrap_state *state, int i)
1215 {
1216 	pt_entry_t contig;
1217 	u_int l2_slot;
1218 	bool first;
1219 
1220 	if ((physmap[i + 1] - state->pa) < L2_SIZE)
1221 		return;
1222 
1223 	/* Make sure there is a valid L1 table */
1224 	pmap_bootstrap_l1_table(state);
1225 
1226 	MPASS((state->va & L2_OFFSET) == 0);
1227 	for (first = true, contig = 0;
1228 	    state->va < DMAP_MAX_ADDRESS &&
1229 	    (physmap[i + 1] - state->pa) >= L2_SIZE;
1230 	    state->va += L2_SIZE, state->pa += L2_SIZE) {
1231 		/*
1232 		 * Stop if we are about to walk off the end of what the
1233 		 * current L1 slot can address.
1234 		 */
1235 		if (!first && (state->pa & L1_OFFSET) == 0)
1236 			break;
1237 
1238 		/*
1239 		 * If we have an aligned, contiguous chunk of L2C_ENTRIES
1240 		 * L2 blocks, set the contiguous bit within each PTE so that
1241 		 * the chunk can be cached using only one TLB entry.
1242 		 */
1243 		if ((state->pa & L2C_OFFSET) == 0) {
1244 			if (state->va + L2C_SIZE < DMAP_MAX_ADDRESS &&
1245 			    physmap[i + 1] - state->pa >= L2C_SIZE) {
1246 				contig = ATTR_CONTIGUOUS;
1247 			} else {
1248 				contig = 0;
1249 			}
1250 		}
1251 
1252 		first = false;
1253 		l2_slot = pmap_l2_index(state->va);
1254 		MPASS((state->pa & L2_OFFSET) == 0);
1255 		MPASS(state->l2[l2_slot] == 0);
1256 		pmap_store(&state->l2[l2_slot], PHYS_TO_PTE(state->pa) |
1257 		    ATTR_AF | pmap_sh_attr | ATTR_S1_XN | ATTR_KERN_GP |
1258 		    ATTR_S1_IDX(VM_MEMATTR_WRITE_BACK) | contig | L2_BLOCK);
1259 	}
1260 	MPASS(state->va == (state->pa - dmap_phys_base + DMAP_MIN_ADDRESS));
1261 }
1262 
1263 static void
1264 pmap_bootstrap_l3_page(struct pmap_bootstrap_state *state, int i)
1265 {
1266 	pt_entry_t contig;
1267 	u_int l3_slot;
1268 	bool first;
1269 
1270 	if (physmap[i + 1] - state->pa < L3_SIZE)
1271 		return;
1272 
1273 	/* Make sure there is a valid L2 table */
1274 	pmap_bootstrap_l2_table(state);
1275 
1276 	MPASS((state->va & L3_OFFSET) == 0);
1277 	for (first = true, contig = 0;
1278 	    state->va < DMAP_MAX_ADDRESS &&
1279 	    physmap[i + 1] - state->pa >= L3_SIZE;
1280 	    state->va += L3_SIZE, state->pa += L3_SIZE) {
1281 		/*
1282 		 * Stop if we are about to walk off the end of what the
1283 		 * current L2 slot can address.
1284 		 */
1285 		if (!first && (state->pa & L2_OFFSET) == 0)
1286 			break;
1287 
1288 		/*
1289 		 * If we have an aligned, contiguous chunk of L3C_ENTRIES
1290 		 * L3 pages, set the contiguous bit within each PTE so that
1291 		 * the chunk can be cached using only one TLB entry.
1292 		 */
1293 		if ((state->pa & L3C_OFFSET) == 0) {
1294 			if (state->va + L3C_SIZE < DMAP_MAX_ADDRESS &&
1295 			    physmap[i + 1] - state->pa >= L3C_SIZE) {
1296 				contig = ATTR_CONTIGUOUS;
1297 			} else {
1298 				contig = 0;
1299 			}
1300 		}
1301 
1302 		first = false;
1303 		l3_slot = pmap_l3_index(state->va);
1304 		MPASS((state->pa & L3_OFFSET) == 0);
1305 		MPASS(state->l3[l3_slot] == 0);
1306 		pmap_store(&state->l3[l3_slot], PHYS_TO_PTE(state->pa) |
1307 		    ATTR_AF | pmap_sh_attr | ATTR_S1_XN | ATTR_KERN_GP |
1308 		    ATTR_S1_IDX(VM_MEMATTR_WRITE_BACK) | contig | L3_PAGE);
1309 	}
1310 	MPASS(state->va == (state->pa - dmap_phys_base + DMAP_MIN_ADDRESS));
1311 }
1312 
1313 void
1314 pmap_bootstrap_dmap(vm_size_t kernlen)
1315 {
1316 	vm_paddr_t start_pa, pa;
1317 	uint64_t tcr;
1318 	int i;
1319 
1320 	tcr = READ_SPECIALREG(tcr_el1);
1321 
1322 	/* Verify that the ASID is set through TTBR0. */
1323 	KASSERT((tcr & TCR_A1) == 0, ("pmap_bootstrap: TCR_EL1.A1 != 0"));
1324 
1325 	if ((tcr & TCR_DS) != 0)
1326 		pmap_lpa_enabled = true;
1327 
1328 	pmap_l1_supported = L1_BLOCKS_SUPPORTED;
1329 
1330 	start_pa = pmap_early_vtophys(KERNBASE);
1331 
1332 	bs_state.freemempos = KERNBASE + kernlen;
1333 	bs_state.freemempos = roundup2(bs_state.freemempos, PAGE_SIZE);
1334 
1335 	/* Fill in physmap array. */
1336 	physmap_idx = physmem_avail(physmap, nitems(physmap));
1337 
1338 	dmap_phys_base = physmap[0] & ~L1_OFFSET;
1339 	dmap_phys_max = 0;
1340 	dmap_max_addr = 0;
1341 
1342 	for (i = 0; i < physmap_idx; i += 2) {
1343 		bs_state.pa = physmap[i] & ~L3_OFFSET;
1344 		bs_state.va = bs_state.pa - dmap_phys_base + DMAP_MIN_ADDRESS;
1345 
1346 		/* Create L3 mappings at the start of the region */
1347 		if ((bs_state.pa & L2_OFFSET) != 0)
1348 			pmap_bootstrap_l3_page(&bs_state, i);
1349 		MPASS(bs_state.pa <= physmap[i + 1]);
1350 
1351 		if (L1_BLOCKS_SUPPORTED) {
1352 			/* Create L2 mappings at the start of the region */
1353 			if ((bs_state.pa & L1_OFFSET) != 0)
1354 				pmap_bootstrap_l2_block(&bs_state, i);
1355 			MPASS(bs_state.pa <= physmap[i + 1]);
1356 
1357 			/* Create the main L1 block mappings */
1358 			for (; bs_state.va < DMAP_MAX_ADDRESS &&
1359 			    (physmap[i + 1] - bs_state.pa) >= L1_SIZE;
1360 			    bs_state.va += L1_SIZE, bs_state.pa += L1_SIZE) {
1361 				/* Make sure there is a valid L1 table */
1362 				pmap_bootstrap_l0_table(&bs_state);
1363 				MPASS((bs_state.pa & L1_OFFSET) == 0);
1364 				pmap_store(
1365 				    &bs_state.l1[pmap_l1_index(bs_state.va)],
1366 				    PHYS_TO_PTE(bs_state.pa) | ATTR_AF |
1367 				    pmap_sh_attr |
1368 				    ATTR_S1_IDX(VM_MEMATTR_WRITE_BACK) |
1369 				    ATTR_S1_XN | ATTR_KERN_GP | L1_BLOCK);
1370 			}
1371 			MPASS(bs_state.pa <= physmap[i + 1]);
1372 
1373 			/* Create L2 mappings at the end of the region */
1374 			pmap_bootstrap_l2_block(&bs_state, i);
1375 		} else {
1376 			while (bs_state.va < DMAP_MAX_ADDRESS &&
1377 			    (physmap[i + 1] - bs_state.pa) >= L2_SIZE) {
1378 				pmap_bootstrap_l2_block(&bs_state, i);
1379 			}
1380 		}
1381 		MPASS(bs_state.pa <= physmap[i + 1]);
1382 
1383 		/* Create L3 mappings at the end of the region */
1384 		pmap_bootstrap_l3_page(&bs_state, i);
1385 		MPASS(bs_state.pa == physmap[i + 1]);
1386 
1387 		if (bs_state.pa > dmap_phys_max) {
1388 			dmap_phys_max = bs_state.pa;
1389 			dmap_max_addr = bs_state.va;
1390 		}
1391 	}
1392 
1393 	pmap_s1_invalidate_all_kernel();
1394 
1395 	bs_state.dmap_valid = true;
1396 
1397 	/* Exclude the kernel and DMAP region */
1398 	pa = pmap_early_vtophys(bs_state.freemempos);
1399 	physmem_exclude_region(start_pa, pa - start_pa, EXFLAG_NOALLOC);
1400 }
1401 
1402 static void
1403 pmap_bootstrap_l2(vm_offset_t va)
1404 {
1405 	KASSERT((va & L1_OFFSET) == 0, ("Invalid virtual address"));
1406 
1407 	/* Leave bs_state.pa as it's only needed to bootstrap blocks and pages*/
1408 	bs_state.va = va;
1409 
1410 	for (; bs_state.va < VM_MAX_KERNEL_ADDRESS; bs_state.va += L1_SIZE)
1411 		pmap_bootstrap_l1_table(&bs_state);
1412 }
1413 
1414 static void
1415 pmap_bootstrap_l3(vm_offset_t va)
1416 {
1417 	KASSERT((va & L2_OFFSET) == 0, ("Invalid virtual address"));
1418 
1419 	/* Leave bs_state.pa as it's only needed to bootstrap blocks and pages*/
1420 	bs_state.va = va;
1421 
1422 	for (; bs_state.va < VM_MAX_KERNEL_ADDRESS; bs_state.va += L2_SIZE)
1423 		pmap_bootstrap_l2_table(&bs_state);
1424 }
1425 
1426 /*
1427  *	Bootstrap the system enough to run with virtual memory.
1428  */
1429 void
1430 pmap_bootstrap(void)
1431 {
1432 	vm_offset_t dpcpu, msgbufpv;
1433 	vm_paddr_t start_pa, pa;
1434 	size_t largest_phys_size;
1435 
1436 	/* Set this early so we can use the pagetable walking functions */
1437 	kernel_pmap_store.pm_l0 = pagetable_l0_ttbr1;
1438 	mtx_init(&kernel_pmap->pm_mtx, "kernel pmap", NULL, MTX_DEF);
1439 	kernel_pmap->pm_l0_paddr =
1440 	    pmap_early_vtophys((vm_offset_t)kernel_pmap_store.pm_l0);
1441 	TAILQ_INIT(&kernel_pmap->pm_pvchunk);
1442 	vm_radix_init(&kernel_pmap->pm_root);
1443 	kernel_pmap->pm_cookie = COOKIE_FROM(-1, INT_MIN);
1444 	kernel_pmap->pm_stage = PM_STAGE1;
1445 	kernel_pmap->pm_levels = 4;
1446 	kernel_pmap->pm_ttbr = kernel_pmap->pm_l0_paddr;
1447 	kernel_pmap->pm_asid_set = &asids;
1448 
1449 	/* Reserve some VA space for early BIOS/ACPI mapping */
1450 	preinit_map_va = roundup2(bs_state.freemempos, L2_SIZE);
1451 
1452 	virtual_avail = preinit_map_va + PMAP_PREINIT_MAPPING_SIZE;
1453 	virtual_avail = roundup2(virtual_avail, L1_SIZE);
1454 	virtual_end = VM_MAX_KERNEL_ADDRESS - PMAP_MAPDEV_EARLY_SIZE - L2_SIZE;
1455 	kernel_vm_end = virtual_avail;
1456 
1457 	/*
1458 	 * We only use PXN when we know nothing will be executed from it, e.g.
1459 	 * the DMAP region.
1460 	 */
1461 	bs_state.table_attrs &= ~TATTR_PXN_TABLE;
1462 
1463 	/*
1464 	 * Find the physical memory we could use. This needs to be after we
1465 	 * exclude any memory that is mapped into the DMAP region but should
1466 	 * not be used by the kernel, e.g. some UEFI memory types.
1467 	 */
1468 	physmap_idx = physmem_avail(physmap, nitems(physmap));
1469 
1470 	/*
1471 	 * Find space for early allocations. We search for the largest
1472 	 * region. This is because the user may choose a large msgbuf.
1473 	 * This could be smarter, e.g. to allow multiple regions to be
1474 	 * used & switch to the next when one is full.
1475 	 */
1476 	largest_phys_size = 0;
1477 	for (int i = 0; i < physmap_idx; i += 2) {
1478 		if ((physmap[i + 1] - physmap[i]) > largest_phys_size) {
1479 			largest_phys_size = physmap[i + 1] - physmap[i];
1480 			bs_state.freemempos = PHYS_TO_DMAP_ADDR(physmap[i]);
1481 		}
1482 	}
1483 
1484 	start_pa = pmap_early_vtophys(bs_state.freemempos);
1485 
1486 	/*
1487 	 * Create the l2 tables up to VM_MAX_KERNEL_ADDRESS.  We assume that the
1488 	 * loader allocated the first and only l2 page table page used to map
1489 	 * the kernel, preloaded files and module metadata.
1490 	 */
1491 	pmap_bootstrap_l2(KERNBASE + L1_SIZE);
1492 	/* And the l3 tables for the early devmap */
1493 	pmap_bootstrap_l3(VM_MAX_KERNEL_ADDRESS - (PMAP_MAPDEV_EARLY_SIZE));
1494 
1495 	pmap_s1_invalidate_all_kernel();
1496 
1497 #define alloc_pages(var, np)						\
1498 	(var) = bs_state.freemempos;					\
1499 	bs_state.freemempos += (np * PAGE_SIZE);			\
1500 	memset_early((char *)(var), 0, ((np) * PAGE_SIZE));
1501 
1502 	/* Allocate dynamic per-cpu area. */
1503 	alloc_pages(dpcpu, DPCPU_SIZE / PAGE_SIZE);
1504 	dpcpu_init((void *)dpcpu, 0);
1505 
1506 	/* Allocate memory for the msgbuf, e.g. for /sbin/dmesg */
1507 	alloc_pages(msgbufpv, round_page(msgbufsize) / PAGE_SIZE);
1508 	msgbufp = (void *)msgbufpv;
1509 
1510 	/* Allocate space for the CPU0 CMAP */
1511 	bs_state.va = virtual_end;
1512 	pmap_bootstrap_l2_table(&bs_state);
1513 	pmap_store(&bs_state.l3[pmap_l3_index(bs_state.va)],
1514 	    PHYS_TO_PTE(pmap_early_vtophys((vm_offset_t)bs_state.l3)) |
1515 	    ATTR_AF | pmap_sh_attr | ATTR_S1_XN | ATTR_KERN_GP |
1516 	    ATTR_S1_IDX(VM_MEMATTR_WRITE_BACK) | L3_PAGE);
1517 	dsb(ishst);
1518 
1519 	mtx_init(&cmap_lock, "SYSMAPS", NULL, MTX_DEF);
1520 	cmap1_addr = (void *)(virtual_end + L3_SIZE);
1521 	cmap1_pte = &bs_state.l3[pmap_l3_index((vm_offset_t)cmap1_addr)];
1522 
1523 	pa = pmap_early_vtophys(bs_state.freemempos);
1524 
1525 	physmem_exclude_region(start_pa, pa - start_pa, EXFLAG_NOALLOC);
1526 }
1527 
1528 #if defined(KASAN) || defined(KMSAN)
1529 static void
1530 pmap_bootstrap_allocate_san_l2(vm_paddr_t start_pa, vm_paddr_t end_pa,
1531     vm_offset_t *vap, vm_offset_t eva)
1532 {
1533 	vm_paddr_t pa;
1534 	vm_offset_t va;
1535 	pd_entry_t *l2;
1536 
1537 	va = *vap;
1538 	pa = rounddown2(end_pa - L2_SIZE, L2_SIZE);
1539 	for (; pa >= start_pa && va < eva; va += L2_SIZE, pa -= L2_SIZE) {
1540 		l2 = pmap_l2(kernel_pmap, va);
1541 
1542 		/*
1543 		 * KASAN stack checking results in us having already allocated
1544 		 * part of our shadow map, so we can just skip those segments.
1545 		 */
1546 		if ((pmap_load(l2) & ATTR_DESCR_VALID) != 0) {
1547 			pa += L2_SIZE;
1548 			continue;
1549 		}
1550 
1551 		bzero_early(PHYS_TO_DMAP(pa), L2_SIZE);
1552 		physmem_exclude_region(pa, L2_SIZE, EXFLAG_NOALLOC);
1553 		pmap_store(l2, PHYS_TO_PTE(pa) | PMAP_SAN_PTE_BITS | L2_BLOCK);
1554 	}
1555 	*vap = va;
1556 }
1557 
1558 /*
1559  * Finish constructing the initial shadow map:
1560  * - Count how many pages from KERNBASE to virtual_avail (scaled for
1561  *   shadow map)
1562  * - Map that entire range using L2 superpages.
1563  */
1564 static void
1565 pmap_bootstrap_san1(vm_offset_t va, int scale)
1566 {
1567 	vm_offset_t eva;
1568 	vm_paddr_t kernstart;
1569 	int i;
1570 
1571 	kernstart = pmap_early_vtophys(KERNBASE);
1572 
1573 	/*
1574 	 * Rebuild physmap one more time, we may have excluded more regions from
1575 	 * allocation since pmap_bootstrap().
1576 	 */
1577 	physmap_idx = physmem_avail(physmap, nitems(physmap));
1578 
1579 	eva = va + (virtual_avail - VM_MIN_KERNEL_ADDRESS) / scale;
1580 
1581 	/*
1582 	 * Find a slot in the physmap large enough for what we needed.  We try to put
1583 	 * the shadow map as high up as we can to avoid depleting the lower 4GB in case
1584 	 * it's needed for, e.g., an xhci controller that can only do 32-bit DMA.
1585 	 */
1586 	for (i = physmap_idx - 2; i >= 0; i -= 2) {
1587 		vm_paddr_t plow, phigh;
1588 
1589 		/* L2 mappings must be backed by memory that is L2-aligned */
1590 		plow = roundup2(physmap[i], L2_SIZE);
1591 		phigh = physmap[i + 1];
1592 		if (plow >= phigh)
1593 			continue;
1594 		if (kernstart >= plow && kernstart < phigh)
1595 			phigh = kernstart;
1596 		if (phigh - plow >= L2_SIZE) {
1597 			pmap_bootstrap_allocate_san_l2(plow, phigh, &va, eva);
1598 			if (va >= eva)
1599 				break;
1600 		}
1601 	}
1602 	if (i < 0)
1603 		panic("Could not find phys region for shadow map");
1604 
1605 	/*
1606 	 * Done. We should now have a valid shadow address mapped for all KVA
1607 	 * that has been mapped so far, i.e., KERNBASE to virtual_avail. Thus,
1608 	 * shadow accesses by the sanitizer runtime will succeed for this range.
1609 	 * When the kernel virtual address range is later expanded, as will
1610 	 * happen in vm_mem_init(), the shadow map will be grown as well. This
1611 	 * is handled by pmap_san_enter().
1612 	 */
1613 }
1614 
1615 void
1616 pmap_bootstrap_san(void)
1617 {
1618 #ifdef KASAN
1619 	pmap_bootstrap_san1(KASAN_MIN_ADDRESS, KASAN_SHADOW_SCALE);
1620 #else
1621 	static uint8_t kmsan_shad_ptp[PAGE_SIZE * 2] __aligned(PAGE_SIZE);
1622 	static uint8_t kmsan_orig_ptp[PAGE_SIZE * 2] __aligned(PAGE_SIZE);
1623 	pd_entry_t *l0, *l1;
1624 
1625 	if (virtual_avail - VM_MIN_KERNEL_ADDRESS > L1_SIZE)
1626 		panic("initial kernel map is too large");
1627 
1628 	l0 = pmap_l0(kernel_pmap, KMSAN_SHAD_MIN_ADDRESS);
1629 	pmap_store(l0, L0_TABLE | PHYS_TO_PTE(
1630 	    pmap_early_vtophys((vm_offset_t)kmsan_shad_ptp)));
1631 	l1 = pmap_l0_to_l1(l0, KMSAN_SHAD_MIN_ADDRESS);
1632 	pmap_store(l1, L1_TABLE | PHYS_TO_PTE(
1633 	    pmap_early_vtophys((vm_offset_t)kmsan_shad_ptp + PAGE_SIZE)));
1634 	pmap_bootstrap_san1(KMSAN_SHAD_MIN_ADDRESS, 1);
1635 
1636 	l0 = pmap_l0(kernel_pmap, KMSAN_ORIG_MIN_ADDRESS);
1637 	pmap_store(l0, L0_TABLE | PHYS_TO_PTE(
1638 	    pmap_early_vtophys((vm_offset_t)kmsan_orig_ptp)));
1639 	l1 = pmap_l0_to_l1(l0, KMSAN_ORIG_MIN_ADDRESS);
1640 	pmap_store(l1, L1_TABLE | PHYS_TO_PTE(
1641 	    pmap_early_vtophys((vm_offset_t)kmsan_orig_ptp + PAGE_SIZE)));
1642 	pmap_bootstrap_san1(KMSAN_ORIG_MIN_ADDRESS, 1);
1643 #endif
1644 }
1645 #endif
1646 
1647 /*
1648  *	Initialize a vm_page's machine-dependent fields.
1649  */
1650 void
1651 pmap_page_init(vm_page_t m)
1652 {
1653 
1654 	TAILQ_INIT(&m->md.pv_list);
1655 	m->md.pv_memattr = VM_MEMATTR_WRITE_BACK;
1656 	m->md.pv_flags = 0;
1657 }
1658 
1659 static void
1660 pmap_init_asids(struct asid_set *set, int bits)
1661 {
1662 	int i;
1663 
1664 	set->asid_bits = bits;
1665 
1666 	/*
1667 	 * We may be too early in the overall initialization process to use
1668 	 * bit_alloc().
1669 	 */
1670 	set->asid_set_size = 1 << set->asid_bits;
1671 	set->asid_set = kmem_malloc(bitstr_size(set->asid_set_size),
1672 	    M_WAITOK | M_ZERO);
1673 	for (i = 0; i < ASID_FIRST_AVAILABLE; i++)
1674 		bit_set(set->asid_set, i);
1675 	set->asid_next = ASID_FIRST_AVAILABLE;
1676 	mtx_init(&set->asid_set_mutex, "asid set", NULL, MTX_SPIN);
1677 }
1678 
1679 static void
1680 pmap_init_pv_table(void)
1681 {
1682 	struct vm_phys_seg *seg, *next_seg;
1683 	struct pmap_large_md_page *pvd;
1684 	vm_size_t s;
1685 	int domain, i, j, pages;
1686 
1687 	/*
1688 	 * We depend on the size being evenly divisible into a page so
1689 	 * that the pv_table array can be indexed directly while
1690 	 * safely spanning multiple pages from different domains.
1691 	 */
1692 	CTASSERT(PAGE_SIZE % sizeof(*pvd) == 0);
1693 
1694 	/*
1695 	 * Calculate the size of the array.
1696 	 */
1697 	s = 0;
1698 	for (i = 0; i < vm_phys_nsegs; i++) {
1699 		seg = &vm_phys_segs[i];
1700 		pages = pmap_l2_pindex(roundup2(seg->end, L2_SIZE)) -
1701 		    pmap_l2_pindex(seg->start);
1702 		s += round_page(pages * sizeof(*pvd));
1703 	}
1704 	pv_table = kva_alloc(s);
1705 	if (pv_table == NULL)
1706 		panic("%s: kva_alloc failed\n", __func__);
1707 
1708 	/*
1709 	 * Iterate physical segments to allocate domain-local memory for PV
1710 	 * list headers.
1711 	 */
1712 	pvd = pv_table;
1713 	for (i = 0; i < vm_phys_nsegs; i++) {
1714 		seg = &vm_phys_segs[i];
1715 		pages = pmap_l2_pindex(roundup2(seg->end, L2_SIZE)) -
1716 		    pmap_l2_pindex(seg->start);
1717 		domain = seg->domain;
1718 
1719 		s = round_page(pages * sizeof(*pvd));
1720 
1721 		for (j = 0; j < s; j += PAGE_SIZE) {
1722 			vm_page_t m = vm_page_alloc_noobj_domain(domain,
1723 			    VM_ALLOC_ZERO);
1724 			if (m == NULL)
1725 				panic("failed to allocate PV table page");
1726 			pmap_qenter((char *)pvd + j, &m, 1);
1727 		}
1728 
1729 		for (j = 0; j < s / sizeof(*pvd); j++) {
1730 			rw_init_flags(&pvd->pv_lock, "pmap pv list", RW_NEW);
1731 			TAILQ_INIT(&pvd->pv_page.pv_list);
1732 			pvd++;
1733 		}
1734 	}
1735 	pvd = &pv_dummy_large;
1736 	memset(pvd, 0, sizeof(*pvd));
1737 	rw_init_flags(&pvd->pv_lock, "pmap pv list dummy", RW_NEW);
1738 	TAILQ_INIT(&pvd->pv_page.pv_list);
1739 
1740 	/*
1741 	 * Set pointers from vm_phys_segs to pv_table.
1742 	 */
1743 	for (i = 0, pvd = pv_table; i < vm_phys_nsegs; i++) {
1744 		seg = &vm_phys_segs[i];
1745 		seg->md_first = pvd;
1746 		pvd += pmap_l2_pindex(roundup2(seg->end, L2_SIZE)) -
1747 		    pmap_l2_pindex(seg->start);
1748 
1749 		/*
1750 		 * If there is a following segment, and the final
1751 		 * superpage of this segment and the initial superpage
1752 		 * of the next segment are the same then adjust the
1753 		 * pv_table entry for that next segment down by one so
1754 		 * that the pv_table entries will be shared.
1755 		 */
1756 		if (i + 1 < vm_phys_nsegs) {
1757 			next_seg = &vm_phys_segs[i + 1];
1758 			if (pmap_l2_pindex(roundup2(seg->end, L2_SIZE)) - 1 ==
1759 			    pmap_l2_pindex(next_seg->start)) {
1760 				pvd--;
1761 			}
1762 		}
1763 	}
1764 }
1765 
1766 static cpu_feat_en
1767 pmap_dbm_check(const struct cpu_feat *feat __unused, u_int midr __unused)
1768 {
1769 	uint64_t id_aa64mmfr1;
1770 
1771 	id_aa64mmfr1 = READ_SPECIALREG(id_aa64mmfr1_el1);
1772 	if (ID_AA64MMFR1_HAFDBS_VAL(id_aa64mmfr1) >=
1773 	    ID_AA64MMFR1_HAFDBS_AF_DBS)
1774 		return (FEAT_DEFAULT_ENABLE);
1775 
1776 	return (FEAT_ALWAYS_DISABLE);
1777 }
1778 
1779 static bool
1780 pmap_dbm_has_errata(const struct cpu_feat *feat __unused, u_int midr,
1781     u_int **errata_list, u_int *errata_count)
1782 {
1783 	/* Disable on Cortex-A55 for erratum 1024718 - all revisions */
1784 	if (CPU_IMPL(midr) == CPU_IMPL_ARM &&
1785 	    CPU_PART(midr) == CPU_PART_CORTEX_A55) {
1786 		static u_int errata_id = 1024718;
1787 
1788 		*errata_list = &errata_id;
1789 		*errata_count = 1;
1790 		return (true);
1791 	}
1792 
1793 	/* Disable on Cortex-A510 for erratum 2051678 - r0p0 to r0p2 */
1794 	if (midr_check_var_part_range(midr, CPU_IMPL_ARM, CPU_PART_CORTEX_A510,
1795 	    0, 0, 0, 2)) {
1796 		static u_int errata_id = 2051678;
1797 
1798 		*errata_list = &errata_id;
1799 		*errata_count = 1;
1800 		return (true);
1801 	}
1802 
1803 	return (false);
1804 }
1805 
1806 static bool
1807 pmap_dbm_enable(const struct cpu_feat *feat __unused,
1808     cpu_feat_errata errata_status, u_int *errata_list __unused,
1809     u_int errata_count)
1810 {
1811 	uint64_t tcr;
1812 
1813 	/* Skip if there is an erratum affecting DBM */
1814 	if (errata_status != ERRATA_NONE)
1815 		return (false);
1816 
1817 	tcr = READ_SPECIALREG(tcr_el1) | TCR_HD;
1818 	WRITE_SPECIALREG(tcr_el1, tcr);
1819 	isb();
1820 	/* Flush the local TLB for the TCR_HD flag change */
1821 	dsb(nshst);
1822 	__asm __volatile("tlbi vmalle1");
1823 	dsb(nsh);
1824 	isb();
1825 
1826 	return (true);
1827 }
1828 
1829 CPU_FEAT(feat_hafdbs, "Hardware management of the Access flag and dirty state",
1830     pmap_dbm_check, pmap_dbm_has_errata, pmap_dbm_enable, NULL,
1831     CPU_FEAT_AFTER_DEV | CPU_FEAT_PER_CPU);
1832 
1833 static cpu_feat_en
1834 pmap_multiple_tlbi_check(const struct cpu_feat *feat __unused, u_int midr)
1835 {
1836 	/*
1837 	 * ARM C1-Premium erratum 4193780
1838 	 * ARM C1-Ultra erratum 4193780
1839 	 * ARM Cortex-A76 erratum 4193800
1840 	 * ARM Cortex-A76AE erratum 4193801
1841 	 * ARM Cortex-A77 erratum 4193798
1842 	 * ARM Cortex-A78 erratum 4193791
1843 	 * ARM Cortex-A78AE erratum 4193793
1844 	 * ARM Cortex-A78C erratum 4193794
1845 	 * ARM Cortex-A710 erratum 4193788
1846 	 * ARM Cortex-X1 erratum 4193791
1847 	 * ARM Cortex-X1C erratum 4193792
1848 	 * ARM Cortex-X2 erratum 4193788
1849 	 * ARM Cortex-X3 erratum 4193786
1850 	 * ARM Cortex-X4 erratum 4118414
1851 	 * ARM Cortex-X925 erratum 4193781
1852 	 * ARM Neoverse-N1 erratum 4193800
1853 	 * ARM Neoverse-N2 erratum 4193789
1854 	 * ARM Neoverse-V1 erratum 4193790
1855 	 * ARM Neoverse-V2 erratum 4193787
1856 	 * ARM Neoverse-V3 erratum 4193784
1857 	 * ARM Neoverse-V3AE erratum 4193784
1858 	 * Present in all revisions
1859 	 */
1860 	if (CPU_IMPL(midr) == CPU_IMPL_ARM) {
1861 		switch(CPU_PART(midr)) {
1862 		case CPU_PART_C1_PREMIUM:
1863 		case CPU_PART_C1_ULTRA:
1864 		case CPU_PART_CORTEX_A76:
1865 		case CPU_PART_CORTEX_A76AE:
1866 		case CPU_PART_CORTEX_A77:
1867 		case CPU_PART_CORTEX_A78:
1868 		case CPU_PART_CORTEX_A78AE:
1869 		case CPU_PART_CORTEX_A78C:
1870 		case CPU_PART_CORTEX_A710:
1871 		case CPU_PART_CORTEX_X1:
1872 		case CPU_PART_CORTEX_X1C:
1873 		case CPU_PART_CORTEX_X2:
1874 		case CPU_PART_CORTEX_X3:
1875 		case CPU_PART_CORTEX_X4:
1876 		case CPU_PART_CORTEX_X925:
1877 		case CPU_PART_NEOVERSE_N1:
1878 		case CPU_PART_NEOVERSE_N2:
1879 		case CPU_PART_NEOVERSE_V1:
1880 		case CPU_PART_NEOVERSE_V2:
1881 		case CPU_PART_NEOVERSE_V3:
1882 		case CPU_PART_NEOVERSE_V3AE:
1883 			return (FEAT_DEFAULT_ENABLE);
1884 		}
1885 	}
1886 
1887 	/*
1888 	 * Cortex-A55 erratum 2441007 (Cat B rare)
1889 	 * Present in all revisions
1890 	 */
1891 	if (CPU_IMPL(midr) == CPU_IMPL_ARM &&
1892 	    CPU_PART(midr) == CPU_PART_CORTEX_A55)
1893 		return (FEAT_DEFAULT_DISABLE);
1894 
1895 	/*
1896 	 * Cortex-A510 erratum 2441009 (Cat B rare)
1897 	 * Present in r0p0 - r1p1
1898 	 * Fixed in r1p2
1899 	 */
1900 	if (midr_check_var_part_range(midr, CPU_IMPL_ARM, CPU_PART_CORTEX_A510,
1901 	    0, 0, 1, 1))
1902 		return (FEAT_DEFAULT_DISABLE);
1903 
1904 	return (FEAT_ALWAYS_DISABLE);
1905 }
1906 
1907 static bool
1908 pmap_multiple_tlbi_enable(const struct cpu_feat *feat __unused,
1909     cpu_feat_errata errata_status, u_int *errata_list __unused,
1910     u_int errata_count __unused)
1911 {
1912 	pmap_multiple_tlbi = true;
1913 	return (true);
1914 }
1915 
1916 CPU_FEAT(errata_multi_tlbi, "Multiple TLBI errata",
1917     pmap_multiple_tlbi_check, NULL, pmap_multiple_tlbi_enable, NULL,
1918     CPU_FEAT_EARLY_BOOT | CPU_FEAT_PER_CPU);
1919 
1920 static cpu_feat_en
1921 pmap_tlbi_range_check(const struct cpu_feat *feat __unused, u_int midr __unused)
1922 {
1923 	uint64_t reg;
1924 
1925 	/*
1926 	 * Range-based TLBI must be supported by every processor, so this
1927 	 * check is performed CPU_FEAT_AFTER_DEV.
1928 	 */
1929 	get_kernel_reg(ID_AA64ISAR0_EL1, &reg);
1930 	if (ID_AA64ISAR0_TLB_VAL(reg) >= ID_AA64ISAR0_TLB_TLBIOSR)
1931 		return (FEAT_DEFAULT_ENABLE);
1932 
1933 	return (FEAT_ALWAYS_DISABLE);
1934 }
1935 
1936 static bool
1937 pmap_tlbi_range_enable(const struct cpu_feat *feat __unused,
1938     cpu_feat_errata errata_status __unused, u_int *errata_list __unused,
1939     u_int errata_count __unused)
1940 {
1941 	/*
1942 	 * pmap_lpa_enabled must be initialized before range-based TLBI can
1943 	 * be performed.
1944 	 */
1945 	MPASS((READ_SPECIALREG(tcr_el1) & TCR_DS) == 0 || pmap_lpa_enabled);
1946 	pmap_tlbi_range_support = true;
1947 	return (true);
1948 }
1949 
1950 CPU_FEAT(feat_tlbi_range, "Range-based TLBI invalidation",
1951     pmap_tlbi_range_check, NULL, pmap_tlbi_range_enable, NULL,
1952     CPU_FEAT_AFTER_DEV | CPU_FEAT_SYSTEM);
1953 
1954 /*
1955  *	Initialize the pmap module.
1956  *
1957  *	Called by vm_mem_init(), to initialize any structures that the pmap
1958  *	system needs to map virtual memory.
1959  */
1960 void
1961 pmap_init(void)
1962 {
1963 	uint64_t mmfr1;
1964 	int i, vmid_bits;
1965 
1966 	/*
1967 	 * Are large page mappings enabled?
1968 	 */
1969 	TUNABLE_INT_FETCH("vm.pmap.superpages_enabled", &superpages_enabled);
1970 	if (superpages_enabled) {
1971 		KASSERT(MAXPAGESIZES > 1 && pagesizes[1] == 0,
1972 		    ("pmap_init: can't assign to pagesizes[1]"));
1973 		pagesizes[1] = L3C_SIZE;
1974 		KASSERT(MAXPAGESIZES > 2 && pagesizes[2] == 0,
1975 		    ("pmap_init: can't assign to pagesizes[2]"));
1976 		pagesizes[2] = L2_SIZE;
1977 		if (L1_BLOCKS_SUPPORTED) {
1978 			KASSERT(MAXPAGESIZES > 3 && pagesizes[3] == 0,
1979 			    ("pmap_init: can't assign to pagesizes[3]"));
1980 			pagesizes[3] = L1_SIZE;
1981 		}
1982 	}
1983 
1984 	/*
1985 	 * Initialize the ASID allocator.
1986 	 */
1987 	pmap_init_asids(&asids,
1988 	    (READ_SPECIALREG(tcr_el1) & TCR_ASID_16) != 0 ? 16 : 8);
1989 
1990 	if (has_hyp()) {
1991 		mmfr1 = READ_SPECIALREG(id_aa64mmfr1_el1);
1992 		vmid_bits = 8;
1993 
1994 		if (ID_AA64MMFR1_VMIDBits_VAL(mmfr1) ==
1995 		    ID_AA64MMFR1_VMIDBits_16)
1996 			vmid_bits = 16;
1997 		pmap_init_asids(&vmids, vmid_bits);
1998 	}
1999 
2000 	/*
2001 	 * Initialize pv chunk lists.
2002 	 */
2003 	for (i = 0; i < PMAP_MEMDOM; i++) {
2004 		mtx_init(&pv_chunks[i].pvc_lock, "pmap pv chunk list", NULL,
2005 		    MTX_DEF);
2006 		TAILQ_INIT(&pv_chunks[i].pvc_list);
2007 	}
2008 	pmap_init_pv_table();
2009 
2010 	vm_initialized = 1;
2011 }
2012 
2013 static SYSCTL_NODE(_vm_pmap, OID_AUTO, l1, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
2014     "L1 (1GB/64GB) page mapping counters");
2015 
2016 static COUNTER_U64_DEFINE_EARLY(pmap_l1_demotions);
2017 SYSCTL_COUNTER_U64(_vm_pmap_l1, OID_AUTO, demotions, CTLFLAG_RD,
2018     &pmap_l1_demotions, "L1 (1GB/64GB) page demotions");
2019 
2020 SYSCTL_BOOL(_vm_pmap_l1, OID_AUTO, supported, CTLFLAG_RD, &pmap_l1_supported,
2021     0, "L1 blocks are supported");
2022 
2023 static SYSCTL_NODE(_vm_pmap, OID_AUTO, l2c, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
2024     "L2C (32MB/1GB) page mapping counters");
2025 
2026 static COUNTER_U64_DEFINE_EARLY(pmap_l2c_demotions);
2027 SYSCTL_COUNTER_U64(_vm_pmap_l2c, OID_AUTO, demotions, CTLFLAG_RD,
2028     &pmap_l2c_demotions, "L2C (32MB/1GB) page demotions");
2029 
2030 static SYSCTL_NODE(_vm_pmap, OID_AUTO, l2, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
2031     "2MB page mapping counters");
2032 
2033 static COUNTER_U64_DEFINE_EARLY(pmap_l2_demotions);
2034 SYSCTL_COUNTER_U64(_vm_pmap_l2, OID_AUTO, demotions, CTLFLAG_RD,
2035     &pmap_l2_demotions, "L2 (2MB/32MB) page demotions");
2036 
2037 static COUNTER_U64_DEFINE_EARLY(pmap_l2_mappings);
2038 SYSCTL_COUNTER_U64(_vm_pmap_l2, OID_AUTO, mappings, CTLFLAG_RD,
2039     &pmap_l2_mappings, "L2 (2MB/32MB) page mappings");
2040 
2041 static COUNTER_U64_DEFINE_EARLY(pmap_l2_p_failures);
2042 SYSCTL_COUNTER_U64(_vm_pmap_l2, OID_AUTO, p_failures, CTLFLAG_RD,
2043     &pmap_l2_p_failures, "L2 (2MB/32MB) page promotion failures");
2044 
2045 static COUNTER_U64_DEFINE_EARLY(pmap_l2_promotions);
2046 SYSCTL_COUNTER_U64(_vm_pmap_l2, OID_AUTO, promotions, CTLFLAG_RD,
2047     &pmap_l2_promotions, "L2 (2MB/32MB) page promotions");
2048 
2049 static SYSCTL_NODE(_vm_pmap, OID_AUTO, l3c, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
2050     "L3C (64KB/2MB) page mapping counters");
2051 
2052 static COUNTER_U64_DEFINE_EARLY(pmap_l3c_demotions);
2053 SYSCTL_COUNTER_U64(_vm_pmap_l3c, OID_AUTO, demotions, CTLFLAG_RD,
2054     &pmap_l3c_demotions, "L3C (64KB/2MB) page demotions");
2055 
2056 static COUNTER_U64_DEFINE_EARLY(pmap_l3c_mappings);
2057 SYSCTL_COUNTER_U64(_vm_pmap_l3c, OID_AUTO, mappings, CTLFLAG_RD,
2058     &pmap_l3c_mappings, "L3C (64KB/2MB) page mappings");
2059 
2060 static COUNTER_U64_DEFINE_EARLY(pmap_l3c_p_failures);
2061 SYSCTL_COUNTER_U64(_vm_pmap_l3c, OID_AUTO, p_failures, CTLFLAG_RD,
2062     &pmap_l3c_p_failures, "L3C (64KB/2MB) page promotion failures");
2063 
2064 static COUNTER_U64_DEFINE_EARLY(pmap_l3c_promotions);
2065 SYSCTL_COUNTER_U64(_vm_pmap_l3c, OID_AUTO, promotions, CTLFLAG_RD,
2066     &pmap_l3c_promotions, "L3C (64KB/2MB) page promotions");
2067 
2068 /*
2069  * If the given value for "final_only" is false, then any cached intermediate-
2070  * level entries, i.e., L{0,1,2}_TABLE entries, are invalidated in addition to
2071  * any cached final-level entry, i.e., either an L{1,2}_BLOCK or L3_PAGE entry.
2072  * Otherwise, just the cached final-level entry is invalidated.
2073  */
2074 static __inline void
2075 pmap_s1_invalidate_kernel(uint64_t r, bool final_only)
2076 {
2077 	if (final_only)
2078 		__asm __volatile("tlbi vaale1is, %0" : : "r" (r));
2079 	else
2080 		__asm __volatile("tlbi vaae1is, %0" : : "r" (r));
2081 }
2082 
2083 static __inline void
2084 pmap_s1_invalidate_user(uint64_t r, bool final_only)
2085 {
2086 	if (final_only)
2087 		__asm __volatile("tlbi vale1is, %0" : : "r" (r));
2088 	else
2089 		__asm __volatile("tlbi vae1is, %0" : : "r" (r));
2090 }
2091 
2092 /*
2093  * The range-based counterparts to the above.  These may only be performed when
2094  * pmap_tlbi_range_support is true.
2095  */
2096 static __inline void
2097 pmap_s1_invalidate_range_kernel(uint64_t r, bool final_only)
2098 {
2099 	if (final_only)
2100 		__asm __volatile(".arch_extension tlb-rmi	\n"
2101 		    "tlbi rvaale1is, %0				\n"
2102 		    ".arch_extension notlb-rmi" : : "r" (r));
2103 	else
2104 		__asm __volatile(".arch_extension tlb-rmi	\n"
2105 		    "tlbi rvaae1is, %0				\n"
2106 		    ".arch_extension notlb-rmi" : : "r" (r));
2107 }
2108 
2109 static __inline void
2110 pmap_s1_invalidate_range_user(uint64_t r, bool final_only)
2111 {
2112 	if (final_only)
2113 		__asm __volatile(".arch_extension tlb-rmi	\n"
2114 		    "tlbi rvale1is, %0				\n"
2115 		    ".arch_extension notlb-rmi" : : "r" (r));
2116 	else
2117 		__asm __volatile(".arch_extension tlb-rmi	\n"
2118 		    "tlbi rvae1is, %0				\n"
2119 		    ".arch_extension notlb-rmi" : : "r" (r));
2120 }
2121 
2122 /*
2123  * Invalidates any cached final- and optionally intermediate-level TLB entries
2124  * for the specified virtual address in the given virtual address space.
2125  */
2126 static __inline void
2127 pmap_s1_invalidate_page(pmap_t pmap, vm_offset_t va, bool final_only)
2128 {
2129 	uint64_t r;
2130 
2131 	PMAP_ASSERT_STAGE1(pmap);
2132 
2133 	dsb(ishst);
2134 	r = TLBI_VA(va);
2135 	if (pmap == kernel_pmap) {
2136 		pmap_s1_invalidate_kernel(r, final_only);
2137 	} else {
2138 		r |= ASID_TO_OPERAND(COOKIE_TO_ASID(pmap->pm_cookie));
2139 		pmap_s1_invalidate_user(r, final_only);
2140 	}
2141 	if (pmap_multiple_tlbi) {
2142 		dsb(ish);
2143 		__asm __volatile("tlbi	vale1is, xzr" ::: "memory");
2144 	}
2145 	dsb(ish);
2146 	isb();
2147 }
2148 
2149 static __inline void
2150 pmap_s2_invalidate_page(pmap_t pmap, vm_offset_t va, bool final_only)
2151 {
2152 	PMAP_ASSERT_STAGE2(pmap);
2153 	MPASS(pmap_stage2_invalidate_range != NULL);
2154 	pmap_stage2_invalidate_range(pmap_to_ttbr0(pmap), va, va + PAGE_SIZE,
2155 	    final_only);
2156 }
2157 
2158 static __inline void
2159 pmap_invalidate_page(pmap_t pmap, vm_offset_t va, bool final_only)
2160 {
2161 	if (pmap->pm_stage == PM_STAGE1)
2162 		pmap_s1_invalidate_page(pmap, va, final_only);
2163 	else
2164 		pmap_s2_invalidate_page(pmap, va, final_only);
2165 }
2166 
2167 /*
2168  * Invalidates the TLB entries for the mappings in the address range [sva,
2169  * eva), using range-based instructions where possible and single-page
2170  * instructions otherwise.  When range-based invalidation is supported, the
2171  * address range is covered by as few TLBI instructions as possible: the
2172  * largest scale whose unit fits within the remaining address range is
2173  * selected, and up to TLBI_RANGE_MAX_UNITS units are invalidated per
2174  * instruction.  An address that cannot be encoded as a BaseADDR, because
2175  * pmap_lpa_enabled is true and the address is not 64KB aligned, is detected
2176  * using va_mask and invalidated one stride at a time.
2177  */
2178 static __always_inline void
2179 pmap_s1_invalidate_loop(vm_offset_t sva, vm_offset_t eva, vm_offset_t stride,
2180     int va_shift, vm_offset_t va_mask, uint64_t asid, bool kernel,
2181     bool final_only)
2182 {
2183 	uint64_t units;
2184 	vm_size_t pages;
2185 	int scale, unit_shift;
2186 
2187 	for (vm_offset_t va = sva; va < eva;) {
2188 		if (pmap_tlbi_range_support && (va & va_mask) == 0) {
2189 			pages = atop(eva - va);
2190 			if (pages >= TLBI_RANGE_UNIT(0)) {
2191 				scale = TLBI_RANGE_SCALE(pages);
2192 				unit_shift = TLBI_RANGE_UNIT_SHIFT(scale);
2193 				units = ulmin(pages >> unit_shift,
2194 				    TLBI_RANGE_MAX_UNITS);
2195 				if (kernel)
2196 					pmap_s1_invalidate_range_kernel(asid |
2197 					    TLBI_RANGE_FIELDS(va, va_shift,
2198 					    units - 1, scale), final_only);
2199 				else
2200 					pmap_s1_invalidate_range_user(asid |
2201 					    TLBI_RANGE_FIELDS(va, va_shift,
2202 					    units - 1, scale), final_only);
2203 				va += ptoa(units << unit_shift);
2204 				continue;
2205 			}
2206 		}
2207 		if (kernel)
2208 			pmap_s1_invalidate_kernel(asid | TLBI_VA(va),
2209 			    final_only);
2210 		else
2211 			pmap_s1_invalidate_user(asid | TLBI_VA(va),
2212 			    final_only);
2213 		va += stride;
2214 	}
2215 }
2216 
2217 /*
2218  * Use stride L{1,2}_SIZE when invalidating the TLB entries for L{1,2}_BLOCK
2219  * mappings.  Otherwise, use stride L3_SIZE.
2220  */
2221 static __inline void
2222 pmap_s1_invalidate_strided(pmap_t pmap, vm_offset_t sva, vm_offset_t eva,
2223     vm_offset_t stride, bool final_only)
2224 {
2225 	uint64_t asid;
2226 	vm_offset_t va_mask;
2227 	int va_shift;
2228 
2229 	PMAP_ASSERT_STAGE1(pmap);
2230 	va_shift = TLBI_RANGE_VA_SHIFT();
2231 	/* va_mask will be 0 unless pmap_lpa_enabled is true. */
2232 	va_mask = (1ul << va_shift) - PAGE_SIZE;
2233 	dsb(ishst);
2234 	if (pmap == kernel_pmap) {
2235 		pmap_s1_invalidate_loop(sva, eva, stride, va_shift, va_mask,
2236 		    0, true, final_only);
2237 	} else {
2238 		asid = ASID_TO_OPERAND(COOKIE_TO_ASID(pmap->pm_cookie));
2239 		pmap_s1_invalidate_loop(sva, eva, stride, va_shift, va_mask,
2240 		    asid, false, final_only);
2241 	}
2242 	if (pmap_multiple_tlbi) {
2243 		dsb(ish);
2244 		__asm __volatile("tlbi	vale1is, xzr" ::: "memory");
2245 	}
2246 	dsb(ish);
2247 	isb();
2248 }
2249 
2250 /*
2251  * Invalidates any cached final- and optionally intermediate-level TLB entries
2252  * for the specified virtual address range in the given virtual address space.
2253  */
2254 static __inline void
2255 pmap_s1_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva,
2256     bool final_only)
2257 {
2258 	pmap_s1_invalidate_strided(pmap, sva, eva, L3_SIZE, final_only);
2259 }
2260 
2261 static __inline void
2262 pmap_s2_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva,
2263     bool final_only)
2264 {
2265 	PMAP_ASSERT_STAGE2(pmap);
2266 	MPASS(pmap_stage2_invalidate_range != NULL);
2267 	pmap_stage2_invalidate_range(pmap_to_ttbr0(pmap), sva, eva, final_only);
2268 }
2269 
2270 static __inline void
2271 pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva,
2272     bool final_only)
2273 {
2274 	if (pmap->pm_stage == PM_STAGE1)
2275 		pmap_s1_invalidate_range(pmap, sva, eva, final_only);
2276 	else
2277 		pmap_s2_invalidate_range(pmap, sva, eva, final_only);
2278 }
2279 
2280 void
2281 pmap_s1_invalidate_all_kernel(void)
2282 {
2283 	dsb(ishst);
2284 	__asm __volatile("tlbi vmalle1is");
2285 	if (pmap_multiple_tlbi) {
2286 		dsb(ish);
2287 		__asm __volatile("tlbi	vale1is, xzr" ::: "memory");
2288 	}
2289 	dsb(ish);
2290 	isb();
2291 }
2292 
2293 /*
2294  * Invalidates all cached intermediate- and final-level TLB entries for the
2295  * given virtual address space.
2296  */
2297 static __inline void
2298 pmap_s1_invalidate_all(pmap_t pmap)
2299 {
2300 	uint64_t r;
2301 
2302 	PMAP_ASSERT_STAGE1(pmap);
2303 
2304 	dsb(ishst);
2305 	if (pmap == kernel_pmap) {
2306 		__asm __volatile("tlbi vmalle1is");
2307 	} else {
2308 		r = ASID_TO_OPERAND(COOKIE_TO_ASID(pmap->pm_cookie));
2309 		__asm __volatile("tlbi aside1is, %0" : : "r" (r));
2310 	}
2311 	if (pmap_multiple_tlbi) {
2312 		dsb(ish);
2313 		__asm __volatile("tlbi	vale1is, xzr" ::: "memory");
2314 	}
2315 	dsb(ish);
2316 	isb();
2317 }
2318 
2319 static __inline void
2320 pmap_s2_invalidate_all(pmap_t pmap)
2321 {
2322 	PMAP_ASSERT_STAGE2(pmap);
2323 	MPASS(pmap_stage2_invalidate_all != NULL);
2324 	pmap_stage2_invalidate_all(pmap_to_ttbr0(pmap));
2325 }
2326 
2327 static __inline void
2328 pmap_invalidate_all(pmap_t pmap)
2329 {
2330 	if (pmap->pm_stage == PM_STAGE1)
2331 		pmap_s1_invalidate_all(pmap);
2332 	else
2333 		pmap_s2_invalidate_all(pmap);
2334 }
2335 
2336 /*
2337  *	Routine:	pmap_extract
2338  *	Function:
2339  *		Extract the physical page address associated
2340  *		with the given map/virtual_address pair.
2341  */
2342 vm_paddr_t
2343 pmap_extract(pmap_t pmap, vm_offset_t va)
2344 {
2345 	pt_entry_t *pte, tpte;
2346 	vm_paddr_t pa;
2347 	int lvl;
2348 
2349 	pa = 0;
2350 	PMAP_LOCK(pmap);
2351 	/*
2352 	 * Find the block or page map for this virtual address. pmap_pte
2353 	 * will return either a valid block/page entry, or NULL.
2354 	 */
2355 	pte = pmap_pte(pmap, va, &lvl);
2356 	if (pte != NULL) {
2357 		tpte = pmap_load(pte);
2358 		pa = PTE_TO_PHYS(tpte);
2359 		switch(lvl) {
2360 		case 1:
2361 			PMAP_ASSERT_L1_BLOCKS_SUPPORTED;
2362 			KASSERT((tpte & ATTR_DESCR_MASK) == L1_BLOCK,
2363 			    ("pmap_extract: Invalid L1 pte found: %lx",
2364 			    tpte & ATTR_DESCR_MASK));
2365 			pa |= (va & L1_OFFSET);
2366 			break;
2367 		case 2:
2368 			KASSERT((tpte & ATTR_DESCR_MASK) == L2_BLOCK,
2369 			    ("pmap_extract: Invalid L2 pte found: %lx",
2370 			    tpte & ATTR_DESCR_MASK));
2371 			pa |= (va & L2_OFFSET);
2372 			break;
2373 		case 3:
2374 			KASSERT((tpte & ATTR_DESCR_MASK) == L3_PAGE,
2375 			    ("pmap_extract: Invalid L3 pte found: %lx",
2376 			    tpte & ATTR_DESCR_MASK));
2377 			pa |= (va & L3_OFFSET);
2378 			break;
2379 		}
2380 	}
2381 	PMAP_UNLOCK(pmap);
2382 	return (pa);
2383 }
2384 
2385 /*
2386  *	Routine:	pmap_extract_and_hold
2387  *	Function:
2388  *		Atomically extract and hold the physical page
2389  *		with the given pmap and virtual address pair
2390  *		if that mapping permits the given protection.
2391  */
2392 vm_page_t
2393 pmap_extract_and_hold(pmap_t pmap, vm_offset_t va, vm_prot_t prot)
2394 {
2395 	pt_entry_t *pte, tpte;
2396 	vm_offset_t off;
2397 	vm_page_t m;
2398 	int lvl;
2399 	bool use;
2400 
2401 	m = NULL;
2402 	PMAP_LOCK(pmap);
2403 	pte = pmap_pte(pmap, va, &lvl);
2404 	if (pte != NULL) {
2405 		tpte = pmap_load(pte);
2406 
2407 		KASSERT(lvl > 0 && lvl <= 3,
2408 		    ("pmap_extract_and_hold: Invalid level %d", lvl));
2409 		/*
2410 		 * Check that the pte is either a L3 page, or a L1 or L2 block
2411 		 * entry. We can assume L1_BLOCK == L2_BLOCK.
2412 		 */
2413 		KASSERT((lvl == 3 && (tpte & ATTR_DESCR_MASK) == L3_PAGE) ||
2414 		    (lvl < 3 && (tpte & ATTR_DESCR_MASK) == L1_BLOCK),
2415 		    ("pmap_extract_and_hold: Invalid pte at L%d: %lx", lvl,
2416 		     tpte & ATTR_DESCR_MASK));
2417 
2418 		use = false;
2419 		if ((prot & VM_PROT_WRITE) == 0)
2420 			use = true;
2421 		else if (pmap->pm_stage == PM_STAGE1 &&
2422 		    (tpte & ATTR_S1_AP_RW_BIT) == ATTR_S1_AP(ATTR_S1_AP_RW))
2423 			use = true;
2424 		else if (pmap->pm_stage == PM_STAGE2 &&
2425 		    ((tpte & ATTR_S2_S2AP(ATTR_S2_S2AP_WRITE)) ==
2426 		     ATTR_S2_S2AP(ATTR_S2_S2AP_WRITE)))
2427 			use = true;
2428 
2429 		if (use) {
2430 			switch (lvl) {
2431 			case 1:
2432 				off = va & L1_OFFSET;
2433 				break;
2434 			case 2:
2435 				off = va & L2_OFFSET;
2436 				break;
2437 			case 3:
2438 			default:
2439 				off = 0;
2440 			}
2441 			m = PHYS_TO_VM_PAGE(PTE_TO_PHYS(tpte) | off);
2442 			if (m != NULL && !vm_page_wire_mapped(m))
2443 				m = NULL;
2444 		}
2445 	}
2446 	PMAP_UNLOCK(pmap);
2447 	return (m);
2448 }
2449 
2450 /*
2451  * Returns true if the entire kernel virtual address range is mapped
2452  */
2453 static bool
2454 pmap_kmapped_range(void *va, vm_size_t size)
2455 {
2456 	pt_entry_t *pte, tpte;
2457 	vm_offset_t eva, sva;
2458 
2459 	sva = (vm_offset_t)va;
2460 	KASSERT(sva >= VM_MIN_KERNEL_ADDRESS,
2461 	    ("%s: Invalid virtual address: %lx", __func__, sva));
2462 	MPASS(size != 0);
2463 	eva = sva + size - 1;
2464 	KASSERT(eva > sva, ("%s: Size too large: sva %lx, size %lx", __func__,
2465 	    sva, size));
2466 
2467 	while (sva <= eva) {
2468 		pte = pmap_l1(kernel_pmap, sva);
2469 		if (pte == NULL)
2470 			return (false);
2471 		tpte = pmap_load(pte);
2472 		if (tpte == 0)
2473 			return (false);
2474 		if ((tpte & ATTR_DESCR_TYPE_MASK) == ATTR_DESCR_TYPE_BLOCK) {
2475 			sva = (sva & ~L1_OFFSET) + L1_SIZE;
2476 			continue;
2477 		}
2478 
2479 		pte = pmap_l1_to_l2(&tpte, sva);
2480 		tpte = pmap_load(pte);
2481 		if (tpte == 0)
2482 			return (false);
2483 		if ((tpte & ATTR_DESCR_TYPE_MASK) == ATTR_DESCR_TYPE_BLOCK) {
2484 			sva = (sva & ~L2_OFFSET) + L2_SIZE;
2485 			continue;
2486 		}
2487 		pte = pmap_l2_to_l3(&tpte, sva);
2488 		tpte = pmap_load(pte);
2489 		if (tpte == 0)
2490 			return (false);
2491 		MPASS((tpte & ATTR_DESCR_TYPE_MASK) == ATTR_DESCR_TYPE_PAGE);
2492 		if ((tpte & ATTR_CONTIGUOUS) == ATTR_CONTIGUOUS)
2493 			sva = (sva & ~L3C_OFFSET) + L3C_SIZE;
2494 		else
2495 			sva = (sva & ~L3_OFFSET) + L3_SIZE;
2496 	}
2497 
2498 	return (true);
2499 }
2500 
2501 /*
2502  * Walks the page tables to translate a kernel virtual address to a
2503  * physical address. Returns true if the kva is valid and stores the
2504  * physical address in pa if it is not NULL.
2505  *
2506  * See the comment above data_abort() for the rationale for specifying
2507  * NO_PERTHREAD_SSP here.
2508  */
2509 bool NO_PERTHREAD_SSP
2510 pmap_klookup(vm_offset_t va, vm_paddr_t *pa)
2511 {
2512 	pt_entry_t *pte, tpte;
2513 	register_t intr;
2514 	uint64_t par;
2515 
2516 	/*
2517 	 * Disable interrupts so we don't get interrupted between asking
2518 	 * for address translation, and getting the result back.
2519 	 */
2520 	intr = intr_disable();
2521 	par = arm64_address_translate_s1e1r(va);
2522 	intr_restore(intr);
2523 
2524 	if (PAR_SUCCESS(par)) {
2525 		if (pa != NULL)
2526 			*pa = (par & PAR_PA_MASK) | (va & PAR_LOW_MASK);
2527 		return (true);
2528 	}
2529 
2530 	/*
2531 	 * Fall back to walking the page table. The address translation
2532 	 * instruction may fail when the page is in a break-before-make
2533 	 * sequence. As we only clear the valid bit in said sequence we
2534 	 * can walk the page table to find the physical address.
2535 	 */
2536 
2537 	pte = pmap_l1(kernel_pmap, va);
2538 	if (pte == NULL)
2539 		return (false);
2540 
2541 	/*
2542 	 * A concurrent pmap_update_entry() will clear the entry's valid bit
2543 	 * but leave the rest of the entry unchanged.  Therefore, we treat a
2544 	 * non-zero entry as being valid, and we ignore the valid bit when
2545 	 * determining whether the entry maps a block, page, or table.
2546 	 */
2547 	tpte = pmap_load(pte);
2548 	if (tpte == 0)
2549 		return (false);
2550 	if ((tpte & ATTR_DESCR_TYPE_MASK) == ATTR_DESCR_TYPE_BLOCK) {
2551 		if (pa != NULL)
2552 			*pa = PTE_TO_PHYS(tpte) | (va & L1_OFFSET);
2553 		return (true);
2554 	}
2555 	pte = pmap_l1_to_l2(&tpte, va);
2556 	tpte = pmap_load(pte);
2557 	if (tpte == 0)
2558 		return (false);
2559 	if ((tpte & ATTR_DESCR_TYPE_MASK) == ATTR_DESCR_TYPE_BLOCK) {
2560 		if (pa != NULL)
2561 			*pa = PTE_TO_PHYS(tpte) | (va & L2_OFFSET);
2562 		return (true);
2563 	}
2564 	pte = pmap_l2_to_l3(&tpte, va);
2565 	tpte = pmap_load(pte);
2566 	if (tpte == 0)
2567 		return (false);
2568 	if (pa != NULL)
2569 		*pa = PTE_TO_PHYS(tpte) | (va & L3_OFFSET);
2570 	return (true);
2571 }
2572 
2573 /*
2574  *	Routine:	pmap_kextract
2575  *	Function:
2576  *		Extract the physical page address associated with the given kernel
2577  *		virtual address.
2578  */
2579 vm_paddr_t
2580 pmap_kextract(vm_offset_t va)
2581 {
2582 	vm_paddr_t pa;
2583 
2584 	if (va >= DMAP_MIN_ADDRESS && va < DMAP_MAX_ADDRESS)
2585 		return (DMAP_TO_PHYS(va));
2586 
2587 	if (pmap_klookup(va, &pa) == false)
2588 		return (0);
2589 	return (pa);
2590 }
2591 
2592 /***************************************************
2593  * Low level mapping routines.....
2594  ***************************************************/
2595 
2596 void
2597 pmap_kenter(vm_offset_t sva, vm_size_t size, vm_paddr_t pa, int mode)
2598 {
2599 	pd_entry_t *pde;
2600 	pt_entry_t attr, old_l3e, *pte;
2601 	vm_offset_t va;
2602 	vm_page_t mpte;
2603 	int error, lvl;
2604 
2605 	KASSERT((pa & L3_OFFSET) == 0,
2606 	    ("pmap_kenter: Invalid physical address"));
2607 	KASSERT((sva & L3_OFFSET) == 0,
2608 	    ("pmap_kenter: Invalid virtual address"));
2609 	KASSERT((size & PAGE_MASK) == 0,
2610 	    ("pmap_kenter: Mapping is not page-sized"));
2611 
2612 	/* CCA - Map devices as nonsecure */
2613 	if (in_realm() && (mode == VM_MEMATTR_DEVICE ||
2614 	    mode == VM_MEMATTR_DEVICE_NP))
2615 		pa |= prot_ns_shared_pa;
2616 
2617 	attr = ATTR_AF | pmap_sh_attr | ATTR_S1_AP(ATTR_S1_AP_RW) |
2618 	    ATTR_S1_XN | ATTR_KERN_GP | ATTR_S1_IDX(mode);
2619 	old_l3e = 0;
2620 	va = sva;
2621 	while (size != 0) {
2622 		pde = pmap_pde(kernel_pmap, va, &lvl);
2623 		KASSERT(pde != NULL,
2624 		    ("pmap_kenter: Invalid page entry, va: 0x%lx", va));
2625 		KASSERT(lvl == 2, ("pmap_kenter: Invalid level %d", lvl));
2626 
2627 		/*
2628 		 * If we have an aligned, contiguous chunk of L2_SIZE, try
2629 		 * to create an L2_BLOCK mapping.
2630 		 */
2631 		if ((va & L2_OFFSET) == 0 && size >= L2_SIZE &&
2632 		    (pa & L2_OFFSET) == 0 && vm_initialized) {
2633 			mpte = PTE_TO_VM_PAGE(pmap_load(pde));
2634 			KASSERT(pmap_every_pte_zero(VM_PAGE_TO_PHYS(mpte)),
2635 			    ("pmap_kenter: Unexpected mapping"));
2636 			PMAP_LOCK(kernel_pmap);
2637 			error = pmap_insert_pt_page(kernel_pmap, mpte, false,
2638 			    false);
2639 			if (error == 0) {
2640 				attr &= ~ATTR_CONTIGUOUS;
2641 
2642 				/*
2643 				 * Although the page table page "mpte" should
2644 				 * be devoid of mappings, the TLB might hold
2645 				 * intermediate entries that reference it, so
2646 				 * we perform a single-page invalidation.
2647 				 */
2648 				pmap_update_entry(kernel_pmap, pde,
2649 				    PHYS_TO_PTE(pa) | attr | L2_BLOCK, va,
2650 				    PAGE_SIZE, false);
2651 			}
2652 			PMAP_UNLOCK(kernel_pmap);
2653 			if (error == 0) {
2654 				va += L2_SIZE;
2655 				pa += L2_SIZE;
2656 				size -= L2_SIZE;
2657 				continue;
2658 			}
2659 		}
2660 
2661 		/*
2662 		 * If we have an aligned, contiguous chunk of L3C_ENTRIES
2663 		 * L3 pages, set the contiguous bit within each PTE so that
2664 		 * the chunk can be cached using only one TLB entry.
2665 		 */
2666 		if ((va & L3C_OFFSET) == 0 && (pa & L3C_OFFSET) == 0) {
2667 			if (size >= L3C_SIZE)
2668 				attr |= ATTR_CONTIGUOUS;
2669 			else
2670 				attr &= ~ATTR_CONTIGUOUS;
2671 		}
2672 
2673 		pte = pmap_l2_to_l3(pde, va);
2674 		old_l3e |= pmap_load_store(pte, PHYS_TO_PTE(pa) | attr |
2675 		    L3_PAGE);
2676 
2677 		va += PAGE_SIZE;
2678 		pa += PAGE_SIZE;
2679 		size -= PAGE_SIZE;
2680 	}
2681 	if ((old_l3e & ATTR_DESCR_VALID) != 0)
2682 		pmap_s1_invalidate_range(kernel_pmap, sva, va, true);
2683 	else {
2684 		/*
2685 		 * Because the old entries were invalid and the new mappings
2686 		 * are not executable, an isb is not required.
2687 		 */
2688 		dsb(ishst);
2689 	}
2690 }
2691 
2692 void
2693 pmap_kenter_device(vm_offset_t sva, vm_size_t size, vm_paddr_t pa)
2694 {
2695 
2696 	pmap_kenter(sva, size, pa, VM_MEMATTR_DEVICE);
2697 }
2698 
2699 /*
2700  * Remove a page from the kernel pagetables.
2701  */
2702 void
2703 pmap_kremove(vm_offset_t va)
2704 {
2705 	pt_entry_t *pte;
2706 
2707 	pte = pmap_pte_exists(kernel_pmap, va, 3, __func__);
2708 	KASSERT((pmap_load(pte) & ATTR_CONTIGUOUS) == 0,
2709 	    ("pmap_kremove: unexpected ATTR_CONTIGUOUS"));
2710 	pmap_clear(pte);
2711 	pmap_s1_invalidate_page(kernel_pmap, va, true);
2712 }
2713 
2714 /*
2715  * Remove the specified range of mappings from the kernel address space.
2716  *
2717  * Should only be applied to mappings that were created by pmap_kenter() or
2718  * pmap_kenter_device().  Nothing about this function is actually specific
2719  * to device mappings.
2720  */
2721 void
2722 pmap_kremove_device(vm_offset_t sva, vm_size_t size)
2723 {
2724 	pt_entry_t *ptep, *ptep_end;
2725 	vm_offset_t va;
2726 	int lvl;
2727 
2728 	KASSERT((sva & L3_OFFSET) == 0,
2729 	    ("pmap_kremove_device: Invalid virtual address"));
2730 	KASSERT((size & PAGE_MASK) == 0,
2731 	    ("pmap_kremove_device: Mapping is not page-sized"));
2732 
2733 	va = sva;
2734 	while (size != 0) {
2735 		ptep = pmap_pte(kernel_pmap, va, &lvl);
2736 		KASSERT(ptep != NULL, ("Invalid page table, va: 0x%lx", va));
2737 		switch (lvl) {
2738 		case 2:
2739 			KASSERT((va & L2_OFFSET) == 0,
2740 			    ("Unaligned virtual address"));
2741 			KASSERT(size >= L2_SIZE, ("Insufficient size"));
2742 
2743 			if (va != sva) {
2744 				pmap_s1_invalidate_range(kernel_pmap, sva, va,
2745 				    true);
2746 			}
2747 			pmap_clear(ptep);
2748 			pmap_s1_invalidate_page(kernel_pmap, va, true);
2749 			PMAP_LOCK(kernel_pmap);
2750 			pmap_remove_kernel_l2(kernel_pmap, ptep, va);
2751 			PMAP_UNLOCK(kernel_pmap);
2752 
2753 			va += L2_SIZE;
2754 			sva = va;
2755 			size -= L2_SIZE;
2756 			break;
2757 		case 3:
2758 			if ((pmap_load(ptep) & ATTR_CONTIGUOUS) != 0) {
2759 				KASSERT((va & L3C_OFFSET) == 0,
2760 				    ("Unaligned L3C virtual address"));
2761 				KASSERT(size >= L3C_SIZE,
2762 				    ("Insufficient L3C size"));
2763 
2764 				ptep_end = ptep + L3C_ENTRIES;
2765 				for (; ptep < ptep_end; ptep++)
2766 					pmap_clear(ptep);
2767 
2768 				va += L3C_SIZE;
2769 				size -= L3C_SIZE;
2770 				break;
2771 			}
2772 			pmap_clear(ptep);
2773 
2774 			va += PAGE_SIZE;
2775 			size -= PAGE_SIZE;
2776 			break;
2777 		default:
2778 			__assert_unreachable();
2779 			break;
2780 		}
2781 	}
2782 	if (va != sva)
2783 		pmap_s1_invalidate_range(kernel_pmap, sva, va, true);
2784 }
2785 
2786 /*
2787  *	Used to map a range of physical addresses into kernel
2788  *	virtual address space.
2789  *
2790  *	The value passed in '*virt' is a suggested virtual address for
2791  *	the mapping. Architectures which can support a direct-mapped
2792  *	physical to virtual region can return the appropriate address
2793  *	within that region, leaving '*virt' unchanged. Other
2794  *	architectures should map the pages starting at '*virt' and
2795  *	update '*virt' with the first usable address after the mapped
2796  *	region.
2797  */
2798 void *
2799 pmap_map(vm_offset_t *virt, vm_paddr_t start, vm_paddr_t end, int prot)
2800 {
2801 	return (PHYS_TO_DMAP(start));
2802 }
2803 
2804 /*
2805  * Add a list of wired pages to the kva
2806  * this routine is only used for temporary
2807  * kernel mappings that do not need to have
2808  * page modification or references recorded.
2809  * Note that old mappings are simply written
2810  * over.  The page *must* be wired.
2811  * Note: SMP coherent.  Uses a ranged shootdown IPI.
2812  */
2813 void
2814 pmap_qenter(void *sva, vm_page_t *ma, int count)
2815 {
2816 	pd_entry_t *pde;
2817 	pt_entry_t attr, old_l3e, *pte;
2818 	vm_offset_t va;
2819 	vm_page_t m;
2820 	int i, lvl;
2821 
2822 	old_l3e = 0;
2823 	va = (vm_offset_t)sva;
2824 	for (i = 0; i < count; i++) {
2825 		pde = pmap_pde(kernel_pmap, va, &lvl);
2826 		KASSERT(pde != NULL,
2827 		    ("pmap_qenter: Invalid page entry, va: 0x%lx", va));
2828 		KASSERT(lvl == 2,
2829 		    ("pmap_qenter: Invalid level %d", lvl));
2830 
2831 		m = ma[i];
2832 		attr = ATTR_AF | pmap_sh_attr |
2833 		    ATTR_S1_AP(ATTR_S1_AP_RW) | ATTR_S1_XN |
2834 		    ATTR_KERN_GP | ATTR_S1_IDX(m->md.pv_memattr) | L3_PAGE;
2835 		pte = pmap_l2_to_l3(pde, va);
2836 		old_l3e |= pmap_load_store(pte, VM_PAGE_TO_PTE(m) | attr);
2837 
2838 		va += L3_SIZE;
2839 	}
2840 	if ((old_l3e & ATTR_DESCR_VALID) != 0)
2841 		pmap_s1_invalidate_range(kernel_pmap, (vm_offset_t)sva, va,
2842 		    true);
2843 	else {
2844 		/*
2845 		 * Because the old entries were invalid and the new mappings
2846 		 * are not executable, an isb is not required.
2847 		 */
2848 		dsb(ishst);
2849 	}
2850 }
2851 
2852 /*
2853  * This routine tears out page mappings from the
2854  * kernel -- it is meant only for temporary mappings.
2855  */
2856 void
2857 pmap_qremove(void *sva, int count)
2858 {
2859 	pt_entry_t *pte;
2860 	vm_offset_t va;
2861 
2862 	va = (vm_offset_t)sva;
2863 
2864 	KASSERT(ADDR_IS_CANONICAL(va),
2865 	    ("%s: Address not in canonical form: %p", __func__, sva));
2866 	KASSERT(ADDR_IS_KERNEL(va), ("usermode va %p", sva));
2867 
2868 	while (count-- > 0) {
2869 		pte = pmap_pte_exists(kernel_pmap, va, 3, NULL);
2870 		if (pte != NULL) {
2871 			pmap_clear(pte);
2872 		}
2873 
2874 		va += PAGE_SIZE;
2875 	}
2876 	pmap_s1_invalidate_range(kernel_pmap, (vm_offset_t)sva, va, true);
2877 }
2878 
2879 /***************************************************
2880  * Page table page management routines.....
2881  ***************************************************/
2882 /*
2883  * Schedule the specified unused page table page to be freed.  Specifically,
2884  * add the page to the specified list of pages that will be released to the
2885  * physical memory manager after the TLB has been updated.
2886  */
2887 static __inline void
2888 pmap_add_delayed_free_list(vm_page_t m, struct spglist *free, bool set_PG_ZERO)
2889 {
2890 
2891 	if (set_PG_ZERO)
2892 		m->flags |= PG_ZERO;
2893 	else
2894 		m->flags &= ~PG_ZERO;
2895 	SLIST_INSERT_HEAD(free, m, plinks.s.ss);
2896 }
2897 
2898 /*
2899  * Decrements a page table page's reference count, which is used to record the
2900  * number of valid page table entries within the page.  If the reference count
2901  * drops to zero, then the page table page is unmapped.  Returns true if the
2902  * page table page was unmapped and false otherwise.
2903  */
2904 static inline bool
2905 pmap_unwire_l3(pmap_t pmap, vm_offset_t va, vm_page_t m, struct spglist *free)
2906 {
2907 
2908 	--m->ref_count;
2909 	if (m->ref_count == 0) {
2910 		_pmap_unwire_l3(pmap, va, m, free);
2911 		return (true);
2912 	} else
2913 		return (false);
2914 }
2915 
2916 static void
2917 _pmap_unwire_l3(pmap_t pmap, vm_offset_t va, vm_page_t m, struct spglist *free)
2918 {
2919 
2920 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
2921 	/*
2922 	 * unmap the page table page
2923 	 */
2924 	if (m->pindex >= (NUL2E + NUL1E)) {
2925 		/* l1 page */
2926 		pd_entry_t *l0;
2927 
2928 		l0 = pmap_l0(pmap, va);
2929 		pmap_clear(l0);
2930 	} else if (m->pindex >= NUL2E) {
2931 		/* l2 page */
2932 		pd_entry_t *l1;
2933 
2934 		l1 = pmap_l1(pmap, va);
2935 		pmap_clear(l1);
2936 	} else {
2937 		/* l3 page */
2938 		pd_entry_t *l2;
2939 
2940 		l2 = pmap_l2(pmap, va);
2941 		pmap_clear(l2);
2942 	}
2943 	pmap_resident_count_dec(pmap, 1);
2944 	if (m->pindex < NUL2E) {
2945 		/* We just released an l3, unhold the matching l2 */
2946 		pd_entry_t *l1, tl1;
2947 		vm_page_t l2pg;
2948 
2949 		l1 = pmap_l1(pmap, va);
2950 		tl1 = pmap_load(l1);
2951 		l2pg = PTE_TO_VM_PAGE(tl1);
2952 		pmap_unwire_l3(pmap, va, l2pg, free);
2953 	} else if (m->pindex < (NUL2E + NUL1E)) {
2954 		/* We just released an l2, unhold the matching l1 */
2955 		pd_entry_t *l0, tl0;
2956 		vm_page_t l1pg;
2957 
2958 		l0 = pmap_l0(pmap, va);
2959 		tl0 = pmap_load(l0);
2960 		l1pg = PTE_TO_VM_PAGE(tl0);
2961 		pmap_unwire_l3(pmap, va, l1pg, free);
2962 	}
2963 	pmap_invalidate_page(pmap, va, false);
2964 
2965 	/*
2966 	 * Put page on a list so that it is released after
2967 	 * *ALL* TLB shootdown is done
2968 	 */
2969 	pmap_add_delayed_free_list(m, free, true);
2970 }
2971 
2972 /*
2973  * After removing a page table entry, this routine is used to
2974  * conditionally free the page, and manage the reference count.
2975  */
2976 static int
2977 pmap_unuse_pt(pmap_t pmap, vm_offset_t va, pd_entry_t ptepde,
2978     struct spglist *free)
2979 {
2980 	vm_page_t mpte;
2981 
2982 	KASSERT(ADDR_IS_CANONICAL(va),
2983 	    ("%s: Address not in canonical form: %lx", __func__, va));
2984 	if (ADDR_IS_KERNEL(va))
2985 		return (0);
2986 	KASSERT(ptepde != 0, ("pmap_unuse_pt: ptepde != 0"));
2987 	mpte = PTE_TO_VM_PAGE(ptepde);
2988 	return (pmap_unwire_l3(pmap, va, mpte, free));
2989 }
2990 
2991 /*
2992  * Release a page table page reference after a failed attempt to create a
2993  * mapping.
2994  */
2995 static void
2996 pmap_abort_ptp(pmap_t pmap, vm_offset_t va, vm_page_t mpte)
2997 {
2998 	struct spglist free;
2999 
3000 	SLIST_INIT(&free);
3001 	if (pmap_unwire_l3(pmap, va, mpte, &free))
3002 		vm_page_free_pages_toq(&free, true);
3003 }
3004 
3005 void
3006 pmap_pinit0(pmap_t pmap)
3007 {
3008 
3009 	PMAP_LOCK_INIT(pmap);
3010 	bzero(&pmap->pm_stats, sizeof(pmap->pm_stats));
3011 	pmap->pm_l0_paddr = READ_SPECIALREG(ttbr0_el1);
3012 	pmap->pm_l0 = PHYS_TO_DMAP(pmap->pm_l0_paddr);
3013 	TAILQ_INIT(&pmap->pm_pvchunk);
3014 	vm_radix_init(&pmap->pm_root);
3015 	pmap->pm_cookie = COOKIE_FROM(ASID_RESERVED_FOR_PID_0, INT_MIN);
3016 	pmap->pm_stage = PM_STAGE1;
3017 	pmap->pm_levels = 4;
3018 	pmap->pm_ttbr = pmap->pm_l0_paddr;
3019 	pmap->pm_asid_set = &asids;
3020 	pmap->pm_bti = NULL;
3021 
3022 	PCPU_SET(curpmap, pmap);
3023 }
3024 
3025 int
3026 pmap_pinit_stage(pmap_t pmap, enum pmap_stage stage, int levels)
3027 {
3028 	vm_page_t m;
3029 
3030 	/*
3031 	 * allocate the l0 page
3032 	 */
3033 	m = vm_page_alloc_noobj(VM_ALLOC_WAITOK | VM_ALLOC_WIRED |
3034 	    VM_ALLOC_ZERO);
3035 	pmap->pm_l0_paddr = VM_PAGE_TO_PHYS(m);
3036 	pmap->pm_l0 = PHYS_TO_DMAP(pmap->pm_l0_paddr);
3037 
3038 	TAILQ_INIT(&pmap->pm_pvchunk);
3039 	vm_radix_init(&pmap->pm_root);
3040 	bzero(&pmap->pm_stats, sizeof(pmap->pm_stats));
3041 	pmap->pm_cookie = COOKIE_FROM(-1, INT_MAX);
3042 
3043 	MPASS(levels == 3 || levels == 4);
3044 	pmap->pm_levels = levels;
3045 	pmap->pm_stage = stage;
3046 	pmap->pm_bti = NULL;
3047 	switch (stage) {
3048 	case PM_STAGE1:
3049 		pmap->pm_asid_set = &asids;
3050 		if (pmap_bti_support) {
3051 			pmap->pm_bti = malloc(sizeof(struct rangeset), M_DEVBUF,
3052 			    M_ZERO | M_WAITOK);
3053 			rangeset_init(pmap->pm_bti, bti_dup_range,
3054 			    bti_free_range, pmap, M_NOWAIT);
3055 		}
3056 		break;
3057 	case PM_STAGE2:
3058 		pmap->pm_asid_set = &vmids;
3059 		break;
3060 	default:
3061 		panic("%s: Invalid pmap type %d", __func__, stage);
3062 		break;
3063 	}
3064 
3065 	/* XXX Temporarily disable deferred ASID allocation. */
3066 	pmap_alloc_asid(pmap);
3067 
3068 	/*
3069 	 * Allocate the level 1 entry to use as the root. This will increase
3070 	 * the refcount on the level 1 page so it won't be removed until
3071 	 * pmap_release() is called.
3072 	 */
3073 	if (pmap->pm_levels == 3) {
3074 		PMAP_LOCK(pmap);
3075 		m = _pmap_alloc_l3(pmap, NUL2E + NUL1E, NULL);
3076 		PMAP_UNLOCK(pmap);
3077 	}
3078 	pmap->pm_ttbr = VM_PAGE_TO_PHYS(m);
3079 
3080 	return (1);
3081 }
3082 
3083 int
3084 pmap_pinit(pmap_t pmap)
3085 {
3086 
3087 	return (pmap_pinit_stage(pmap, PM_STAGE1, 4));
3088 }
3089 
3090 /*
3091  * This routine is called if the desired page table page does not exist.
3092  *
3093  * If page table page allocation fails, this routine may sleep before
3094  * returning NULL.  It sleeps only if a lock pointer was given.
3095  *
3096  * Note: If a page allocation fails at page table level two or three,
3097  * one or two pages may be held during the wait, only to be released
3098  * afterwards.  This conservative approach is easily argued to avoid
3099  * race conditions.
3100  */
3101 static vm_page_t
3102 _pmap_alloc_l3(pmap_t pmap, vm_pindex_t ptepindex, struct rwlock **lockp)
3103 {
3104 	vm_page_t m, l1pg, l2pg;
3105 
3106 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
3107 
3108 	/*
3109 	 * Allocate a page table page.
3110 	 */
3111 	if ((m = vm_page_alloc_noobj(VM_ALLOC_WIRED | VM_ALLOC_ZERO)) == NULL) {
3112 		if (lockp != NULL) {
3113 			RELEASE_PV_LIST_LOCK(lockp);
3114 			PMAP_UNLOCK(pmap);
3115 			vm_wait(NULL);
3116 			PMAP_LOCK(pmap);
3117 		}
3118 
3119 		/*
3120 		 * Indicate the need to retry.  While waiting, the page table
3121 		 * page may have been allocated.
3122 		 */
3123 		return (NULL);
3124 	}
3125 	m->pindex = ptepindex;
3126 
3127 	/*
3128 	 * Because of AArch64's weak memory consistency model, we must have a
3129 	 * barrier here to ensure that the stores for zeroing "m", whether by
3130 	 * pmap_zero_page() or an earlier function, are visible before adding
3131 	 * "m" to the page table.  Otherwise, a page table walk by another
3132 	 * processor's MMU could see the mapping to "m" and a stale, non-zero
3133 	 * PTE within "m".
3134 	 */
3135 	dmb(ishst);
3136 
3137 	/*
3138 	 * Map the pagetable page into the process address space, if
3139 	 * it isn't already there.
3140 	 */
3141 
3142 	if (ptepindex >= (NUL2E + NUL1E)) {
3143 		pd_entry_t *l0p, l0e;
3144 		vm_pindex_t l0index;
3145 
3146 		l0index = ptepindex - (NUL2E + NUL1E);
3147 		l0p = &pmap->pm_l0[l0index];
3148 		KASSERT((pmap_load(l0p) & ATTR_DESCR_VALID) == 0,
3149 		    ("%s: L0 entry %#lx is valid", __func__, pmap_load(l0p)));
3150 		l0e = VM_PAGE_TO_PTE(m) | L0_TABLE;
3151 
3152 		/*
3153 		 * Mark all kernel memory as not accessible from userspace
3154 		 * and userspace memory as not executable from the kernel.
3155 		 * This has been done for the bootstrap L0 entries in
3156 		 * locore.S.
3157 		 */
3158 		if (pmap == kernel_pmap)
3159 			l0e |= TATTR_UXN_TABLE | TATTR_AP_TABLE_NO_EL0;
3160 		else
3161 			l0e |= TATTR_PXN_TABLE;
3162 		pmap_store(l0p, l0e);
3163 	} else if (ptepindex >= NUL2E) {
3164 		vm_pindex_t l0index, l1index;
3165 		pd_entry_t *l0, *l1;
3166 		pd_entry_t tl0;
3167 
3168 		l1index = ptepindex - NUL2E;
3169 		l0index = l1index >> Ln_ENTRIES_SHIFT;
3170 
3171 		l0 = &pmap->pm_l0[l0index];
3172 		tl0 = pmap_load(l0);
3173 		if (tl0 == 0) {
3174 			/* recurse for allocating page dir */
3175 			if (_pmap_alloc_l3(pmap, NUL2E + NUL1E + l0index,
3176 			    lockp) == NULL) {
3177 				vm_page_unwire_noq(m);
3178 				vm_page_free_zero(m);
3179 				return (NULL);
3180 			}
3181 		} else {
3182 			l1pg = PTE_TO_VM_PAGE(tl0);
3183 			l1pg->ref_count++;
3184 		}
3185 
3186 		l1 = PHYS_TO_DMAP(PTE_TO_PHYS(pmap_load(l0)));
3187 		l1 = &l1[ptepindex & Ln_ADDR_MASK];
3188 		KASSERT((pmap_load(l1) & ATTR_DESCR_VALID) == 0,
3189 		    ("%s: L1 entry %#lx is valid", __func__, pmap_load(l1)));
3190 		pmap_store(l1, VM_PAGE_TO_PTE(m) | L1_TABLE);
3191 	} else {
3192 		vm_pindex_t l0index, l1index;
3193 		pd_entry_t *l0, *l1, *l2;
3194 		pd_entry_t tl0, tl1;
3195 
3196 		l1index = ptepindex >> Ln_ENTRIES_SHIFT;
3197 		l0index = l1index >> Ln_ENTRIES_SHIFT;
3198 
3199 		l0 = &pmap->pm_l0[l0index];
3200 		tl0 = pmap_load(l0);
3201 		if (tl0 == 0) {
3202 			/* recurse for allocating page dir */
3203 			if (_pmap_alloc_l3(pmap, NUL2E + l1index,
3204 			    lockp) == NULL) {
3205 				vm_page_unwire_noq(m);
3206 				vm_page_free_zero(m);
3207 				return (NULL);
3208 			}
3209 			tl0 = pmap_load(l0);
3210 			l1 = PHYS_TO_DMAP(PTE_TO_PHYS(tl0));
3211 			l1 = &l1[l1index & Ln_ADDR_MASK];
3212 		} else {
3213 			l1 = PHYS_TO_DMAP(PTE_TO_PHYS(tl0));
3214 			l1 = &l1[l1index & Ln_ADDR_MASK];
3215 			tl1 = pmap_load(l1);
3216 			if (tl1 == 0) {
3217 				/* recurse for allocating page dir */
3218 				if (_pmap_alloc_l3(pmap, NUL2E + l1index,
3219 				    lockp) == NULL) {
3220 					vm_page_unwire_noq(m);
3221 					vm_page_free_zero(m);
3222 					return (NULL);
3223 				}
3224 			} else {
3225 				l2pg = PTE_TO_VM_PAGE(tl1);
3226 				l2pg->ref_count++;
3227 			}
3228 		}
3229 
3230 		l2 = PHYS_TO_DMAP(PTE_TO_PHYS(pmap_load(l1)));
3231 		l2 = &l2[ptepindex & Ln_ADDR_MASK];
3232 		KASSERT((pmap_load(l2) & ATTR_DESCR_VALID) == 0,
3233 		    ("%s: L2 entry %#lx is valid", __func__, pmap_load(l2)));
3234 		pmap_store(l2, VM_PAGE_TO_PTE(m) | L2_TABLE);
3235 	}
3236 
3237 	pmap_resident_count_inc(pmap, 1);
3238 
3239 	return (m);
3240 }
3241 
3242 static pd_entry_t *
3243 pmap_alloc_l2(pmap_t pmap, vm_offset_t va, vm_page_t *l2pgp,
3244     struct rwlock **lockp)
3245 {
3246 	pd_entry_t *l1, *l2;
3247 	vm_page_t l2pg;
3248 	vm_pindex_t l2pindex;
3249 
3250 	KASSERT(ADDR_IS_CANONICAL(va),
3251 	    ("%s: Address not in canonical form: %lx", __func__, va));
3252 
3253 retry:
3254 	l1 = pmap_l1(pmap, va);
3255 	if (l1 != NULL && (pmap_load(l1) & ATTR_DESCR_MASK) == L1_TABLE) {
3256 		l2 = pmap_l1_to_l2(l1, va);
3257 		if (ADDR_IS_USER(va)) {
3258 			/* Add a reference to the L2 page. */
3259 			l2pg = PTE_TO_VM_PAGE(pmap_load(l1));
3260 			l2pg->ref_count++;
3261 		} else
3262 			l2pg = NULL;
3263 	} else if (ADDR_IS_USER(va)) {
3264 		/* Allocate a L2 page. */
3265 		l2pindex = pmap_l2_pindex(va) >> Ln_ENTRIES_SHIFT;
3266 		l2pg = _pmap_alloc_l3(pmap, NUL2E + l2pindex, lockp);
3267 		if (l2pg == NULL) {
3268 			if (lockp != NULL)
3269 				goto retry;
3270 			else
3271 				return (NULL);
3272 		}
3273 		l2 = VM_PAGE_TO_DMAP(l2pg);
3274 		l2 = &l2[pmap_l2_index(va)];
3275 	} else
3276 		panic("pmap_alloc_l2: missing page table page for va %#lx",
3277 		    va);
3278 	*l2pgp = l2pg;
3279 	return (l2);
3280 }
3281 
3282 static vm_page_t
3283 pmap_alloc_l3(pmap_t pmap, vm_offset_t va, struct rwlock **lockp)
3284 {
3285 	vm_pindex_t ptepindex;
3286 	pd_entry_t *pde, tpde;
3287 #ifdef INVARIANTS
3288 	pt_entry_t *pte;
3289 #endif
3290 	vm_page_t m;
3291 	int lvl;
3292 
3293 	/*
3294 	 * Calculate pagetable page index
3295 	 */
3296 	ptepindex = pmap_l2_pindex(va);
3297 retry:
3298 	/*
3299 	 * Get the page directory entry
3300 	 */
3301 	pde = pmap_pde(pmap, va, &lvl);
3302 
3303 	/*
3304 	 * If the page table page is mapped, we just increment the hold count,
3305 	 * and activate it. If we get a level 2 pde it will point to a level 3
3306 	 * table.
3307 	 */
3308 	switch (lvl) {
3309 	case -1:
3310 		break;
3311 	case 0:
3312 #ifdef INVARIANTS
3313 		pte = pmap_l0_to_l1(pde, va);
3314 		KASSERT(pmap_load(pte) == 0,
3315 		    ("pmap_alloc_l3: TODO: l0 superpages"));
3316 #endif
3317 		break;
3318 	case 1:
3319 #ifdef INVARIANTS
3320 		pte = pmap_l1_to_l2(pde, va);
3321 		KASSERT(pmap_load(pte) == 0,
3322 		    ("pmap_alloc_l3: TODO: l1 superpages"));
3323 #endif
3324 		break;
3325 	case 2:
3326 		tpde = pmap_load(pde);
3327 		if (tpde != 0) {
3328 			m = PTE_TO_VM_PAGE(tpde);
3329 			m->ref_count++;
3330 			return (m);
3331 		}
3332 		break;
3333 	default:
3334 		panic("pmap_alloc_l3: Invalid level %d", lvl);
3335 	}
3336 
3337 	/*
3338 	 * Here if the pte page isn't mapped, or if it has been deallocated.
3339 	 */
3340 	m = _pmap_alloc_l3(pmap, ptepindex, lockp);
3341 	if (m == NULL && lockp != NULL)
3342 		goto retry;
3343 
3344 	return (m);
3345 }
3346 
3347 /***************************************************
3348  * Pmap allocation/deallocation routines.
3349  ***************************************************/
3350 
3351 /*
3352  * Release any resources held by the given physical map.
3353  * Called when a pmap initialized by pmap_pinit is being released.
3354  * Should only be called if the map contains no valid mappings.
3355  */
3356 void
3357 pmap_release(pmap_t pmap)
3358 {
3359 	bool rv __diagused;
3360 	struct spglist freelist;
3361 	struct asid_set *set;
3362 	vm_page_t m;
3363 	int asid;
3364 
3365 	if (pmap->pm_levels != 4) {
3366 		PMAP_ASSERT_STAGE2(pmap);
3367 		KASSERT(pmap->pm_stats.resident_count == 1,
3368 		    ("pmap_release: pmap resident count %ld != 0",
3369 		    pmap->pm_stats.resident_count));
3370 		KASSERT((pmap->pm_l0[0] & ATTR_DESCR_VALID) == ATTR_DESCR_VALID,
3371 		    ("pmap_release: Invalid l0 entry: %lx", pmap->pm_l0[0]));
3372 
3373 		SLIST_INIT(&freelist);
3374 		m = PHYS_TO_VM_PAGE(pmap->pm_ttbr);
3375 		PMAP_LOCK(pmap);
3376 		rv = pmap_unwire_l3(pmap, 0, m, &freelist);
3377 		PMAP_UNLOCK(pmap);
3378 		MPASS(rv == true);
3379 		vm_page_free_pages_toq(&freelist, true);
3380 	}
3381 
3382 	KASSERT(pmap->pm_stats.resident_count == 0,
3383 	    ("pmap_release: pmap resident count %ld != 0",
3384 	    pmap->pm_stats.resident_count));
3385 	KASSERT(vm_radix_is_empty(&pmap->pm_root),
3386 	    ("pmap_release: pmap has reserved page table page(s)"));
3387 
3388 	set = pmap->pm_asid_set;
3389 	KASSERT(set != NULL, ("%s: NULL asid set", __func__));
3390 
3391 	/*
3392 	 * Allow the ASID to be reused. In stage 2 VMIDs we don't invalidate
3393 	 * the entries when removing them so rely on a later tlb invalidation.
3394 	 * this will happen when updating the VMID generation. Because of this
3395 	 * we don't reuse VMIDs within a generation.
3396 	 */
3397 	if (pmap->pm_stage == PM_STAGE1) {
3398 		mtx_lock_spin(&set->asid_set_mutex);
3399 		if (COOKIE_TO_EPOCH(pmap->pm_cookie) == set->asid_epoch) {
3400 			asid = COOKIE_TO_ASID(pmap->pm_cookie);
3401 			KASSERT(asid >= ASID_FIRST_AVAILABLE &&
3402 			    asid < set->asid_set_size,
3403 			    ("pmap_release: pmap cookie has out-of-range asid"));
3404 			bit_clear(set->asid_set, asid);
3405 		}
3406 		mtx_unlock_spin(&set->asid_set_mutex);
3407 
3408 		if (pmap->pm_bti != NULL) {
3409 			rangeset_fini(pmap->pm_bti);
3410 			free(pmap->pm_bti, M_DEVBUF);
3411 		}
3412 	}
3413 
3414 	m = PHYS_TO_VM_PAGE(pmap->pm_l0_paddr);
3415 	vm_page_unwire_noq(m);
3416 	vm_page_free_zero(m);
3417 }
3418 
3419 static int
3420 kvm_size(SYSCTL_HANDLER_ARGS)
3421 {
3422 	unsigned long ksize = VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS;
3423 
3424 	return sysctl_handle_long(oidp, &ksize, 0, req);
3425 }
3426 SYSCTL_PROC(_vm, OID_AUTO, kvm_size, CTLTYPE_LONG | CTLFLAG_RD | CTLFLAG_MPSAFE,
3427     0, 0, kvm_size, "LU",
3428     "Size of KVM");
3429 
3430 static int
3431 kvm_free(SYSCTL_HANDLER_ARGS)
3432 {
3433 	unsigned long kfree = VM_MAX_KERNEL_ADDRESS - kernel_vm_end;
3434 
3435 	return sysctl_handle_long(oidp, &kfree, 0, req);
3436 }
3437 SYSCTL_PROC(_vm, OID_AUTO, kvm_free, CTLTYPE_LONG | CTLFLAG_RD | CTLFLAG_MPSAFE,
3438     0, 0, kvm_free, "LU",
3439     "Amount of KVM free");
3440 
3441 /*
3442  * grow the number of kernel page table entries, if needed
3443  */
3444 static int
3445 pmap_growkernel_nopanic(vm_offset_t addr)
3446 {
3447 	vm_page_t nkpg;
3448 	pd_entry_t *l0, *l1, *l2;
3449 
3450 	mtx_assert(&kernel_map->system_mtx, MA_OWNED);
3451 
3452 	addr = roundup2(addr, L2_SIZE);
3453 	if (addr - 1 >= vm_map_max(kernel_map))
3454 		addr = vm_map_max(kernel_map);
3455 	if (kernel_vm_end < addr) {
3456 		kasan_shadow_map(kernel_vm_end, addr - kernel_vm_end);
3457 		kmsan_shadow_map(kernel_vm_end, addr - kernel_vm_end);
3458 	}
3459 	while (kernel_vm_end < addr) {
3460 		l0 = pmap_l0(kernel_pmap, kernel_vm_end);
3461 		KASSERT(pmap_load(l0) != 0,
3462 		    ("pmap_growkernel: No level 0 kernel entry"));
3463 
3464 		l1 = pmap_l0_to_l1(l0, kernel_vm_end);
3465 		if (pmap_load(l1) == 0) {
3466 			/* We need a new PDP entry */
3467 			nkpg = vm_page_alloc_noobj(VM_ALLOC_INTERRUPT |
3468 			    VM_ALLOC_NOFREE | VM_ALLOC_WIRED | VM_ALLOC_ZERO);
3469 			if (nkpg == NULL)
3470 				return (KERN_RESOURCE_SHORTAGE);
3471 			nkpg->pindex = pmap_l1_pindex(kernel_vm_end);
3472 			/* See the dmb() in _pmap_alloc_l3(). */
3473 			dmb(ishst);
3474 			pmap_store(l1, VM_PAGE_TO_PTE(nkpg) | L1_TABLE);
3475 			continue; /* try again */
3476 		}
3477 		l2 = pmap_l1_to_l2(l1, kernel_vm_end);
3478 		if (pmap_load(l2) != 0) {
3479 			kernel_vm_end = (kernel_vm_end + L2_SIZE) & ~L2_OFFSET;
3480 			if (kernel_vm_end - 1 >= vm_map_max(kernel_map)) {
3481 				kernel_vm_end = vm_map_max(kernel_map);
3482 				break;
3483 			}
3484 			continue;
3485 		}
3486 
3487 		nkpg = vm_page_alloc_noobj(VM_ALLOC_INTERRUPT |
3488 		    VM_ALLOC_NOFREE | VM_ALLOC_WIRED | VM_ALLOC_ZERO);
3489 		if (nkpg == NULL)
3490 			return (KERN_RESOURCE_SHORTAGE);
3491 		nkpg->pindex = pmap_l2_pindex(kernel_vm_end);
3492 		/* See the dmb() in _pmap_alloc_l3(). */
3493 		dmb(ishst);
3494 		pmap_store(l2, VM_PAGE_TO_PTE(nkpg) | L2_TABLE);
3495 
3496 		kernel_vm_end = (kernel_vm_end + L2_SIZE) & ~L2_OFFSET;
3497 		if (kernel_vm_end - 1 >= vm_map_max(kernel_map)) {
3498 			kernel_vm_end = vm_map_max(kernel_map);
3499 			break;
3500 		}
3501 	}
3502 	return (KERN_SUCCESS);
3503 }
3504 
3505 int
3506 pmap_growkernel(vm_offset_t addr)
3507 {
3508 	int rv;
3509 
3510 	rv = pmap_growkernel_nopanic(addr);
3511 	if (rv != KERN_SUCCESS && pmap_growkernel_panic)
3512 		panic("pmap_growkernel: no memory to grow kernel");
3513 	return (rv);
3514 }
3515 
3516 /***************************************************
3517  * page management routines.
3518  ***************************************************/
3519 
3520 static const uint64_t pc_freemask[_NPCM] = {
3521 	[0 ... _NPCM - 2] = PC_FREEN,
3522 	[_NPCM - 1] = PC_FREEL
3523 };
3524 
3525 #ifdef PV_STATS
3526 static int pc_chunk_count, pc_chunk_allocs, pc_chunk_frees, pc_chunk_tryfail;
3527 
3528 SYSCTL_INT(_vm_pmap, OID_AUTO, pc_chunk_count, CTLFLAG_RD, &pc_chunk_count, 0,
3529 	"Current number of pv entry chunks");
3530 SYSCTL_INT(_vm_pmap, OID_AUTO, pc_chunk_allocs, CTLFLAG_RD, &pc_chunk_allocs, 0,
3531 	"Current number of pv entry chunks allocated");
3532 SYSCTL_INT(_vm_pmap, OID_AUTO, pc_chunk_frees, CTLFLAG_RD, &pc_chunk_frees, 0,
3533 	"Current number of pv entry chunks frees");
3534 SYSCTL_INT(_vm_pmap, OID_AUTO, pc_chunk_tryfail, CTLFLAG_RD, &pc_chunk_tryfail, 0,
3535 	"Number of times tried to get a chunk page but failed.");
3536 
3537 static long pv_entry_frees, pv_entry_allocs, pv_entry_count;
3538 static int pv_entry_spare;
3539 
3540 SYSCTL_LONG(_vm_pmap, OID_AUTO, pv_entry_frees, CTLFLAG_RD, &pv_entry_frees, 0,
3541 	"Current number of pv entry frees");
3542 SYSCTL_LONG(_vm_pmap, OID_AUTO, pv_entry_allocs, CTLFLAG_RD, &pv_entry_allocs, 0,
3543 	"Current number of pv entry allocs");
3544 SYSCTL_LONG(_vm_pmap, OID_AUTO, pv_entry_count, CTLFLAG_RD, &pv_entry_count, 0,
3545 	"Current number of pv entries");
3546 SYSCTL_INT(_vm_pmap, OID_AUTO, pv_entry_spare, CTLFLAG_RD, &pv_entry_spare, 0,
3547 	"Current number of spare pv entries");
3548 #endif
3549 
3550 /*
3551  * We are in a serious low memory condition.  Resort to
3552  * drastic measures to free some pages so we can allocate
3553  * another pv entry chunk.
3554  *
3555  * Returns NULL if PV entries were reclaimed from the specified pmap.
3556  *
3557  * We do not, however, unmap 2mpages because subsequent accesses will
3558  * allocate per-page pv entries until repromotion occurs, thereby
3559  * exacerbating the shortage of free pv entries.
3560  */
3561 static vm_page_t
3562 reclaim_pv_chunk_domain(pmap_t locked_pmap, struct rwlock **lockp, int domain)
3563 {
3564 	struct pv_chunks_list *pvc;
3565 	struct pv_chunk *pc, *pc_marker, *pc_marker_end;
3566 	struct pv_chunk_header pc_marker_b, pc_marker_end_b;
3567 	pd_entry_t *pde;
3568 	pmap_t next_pmap, pmap;
3569 	pt_entry_t *pte, tpte;
3570 	pv_entry_t pv;
3571 	vm_offset_t va;
3572 	vm_page_t m, m_pc;
3573 	struct spglist free;
3574 	uint64_t inuse;
3575 	int bit, field, freed, lvl;
3576 
3577 	PMAP_LOCK_ASSERT(locked_pmap, MA_OWNED);
3578 	KASSERT(lockp != NULL, ("reclaim_pv_chunk: lockp is NULL"));
3579 
3580 	pmap = NULL;
3581 	m_pc = NULL;
3582 	SLIST_INIT(&free);
3583 	bzero(&pc_marker_b, sizeof(pc_marker_b));
3584 	bzero(&pc_marker_end_b, sizeof(pc_marker_end_b));
3585 	pc_marker = (struct pv_chunk *)&pc_marker_b;
3586 	pc_marker_end = (struct pv_chunk *)&pc_marker_end_b;
3587 
3588 	pvc = &pv_chunks[domain];
3589 	mtx_lock(&pvc->pvc_lock);
3590 	pvc->active_reclaims++;
3591 	TAILQ_INSERT_HEAD(&pvc->pvc_list, pc_marker, pc_lru);
3592 	TAILQ_INSERT_TAIL(&pvc->pvc_list, pc_marker_end, pc_lru);
3593 	while ((pc = TAILQ_NEXT(pc_marker, pc_lru)) != pc_marker_end &&
3594 	    SLIST_EMPTY(&free)) {
3595 		next_pmap = pc->pc_pmap;
3596 		if (next_pmap == NULL) {
3597 			/*
3598 			 * The next chunk is a marker.  However, it is
3599 			 * not our marker, so active_reclaims must be
3600 			 * > 1.  Consequently, the next_chunk code
3601 			 * will not rotate the pv_chunks list.
3602 			 */
3603 			goto next_chunk;
3604 		}
3605 		mtx_unlock(&pvc->pvc_lock);
3606 
3607 		/*
3608 		 * A pv_chunk can only be removed from the pc_lru list
3609 		 * when both pvc->pvc_lock is owned and the
3610 		 * corresponding pmap is locked.
3611 		 */
3612 		if (pmap != next_pmap) {
3613 			if (pmap != NULL && pmap != locked_pmap)
3614 				PMAP_UNLOCK(pmap);
3615 			pmap = next_pmap;
3616 			/* Avoid deadlock and lock recursion. */
3617 			if (pmap > locked_pmap) {
3618 				RELEASE_PV_LIST_LOCK(lockp);
3619 				PMAP_LOCK(pmap);
3620 				mtx_lock(&pvc->pvc_lock);
3621 				continue;
3622 			} else if (pmap != locked_pmap) {
3623 				if (PMAP_TRYLOCK(pmap)) {
3624 					mtx_lock(&pvc->pvc_lock);
3625 					continue;
3626 				} else {
3627 					pmap = NULL; /* pmap is not locked */
3628 					mtx_lock(&pvc->pvc_lock);
3629 					pc = TAILQ_NEXT(pc_marker, pc_lru);
3630 					if (pc == NULL ||
3631 					    pc->pc_pmap != next_pmap)
3632 						continue;
3633 					goto next_chunk;
3634 				}
3635 			}
3636 		}
3637 
3638 		/*
3639 		 * Destroy every non-wired, 4 KB page mapping in the chunk.
3640 		 */
3641 		freed = 0;
3642 		for (field = 0; field < _NPCM; field++) {
3643 			for (inuse = ~pc->pc_map[field] & pc_freemask[field];
3644 			    inuse != 0; inuse &= ~(1UL << bit)) {
3645 				bit = ffsl(inuse) - 1;
3646 				pv = &pc->pc_pventry[field * 64 + bit];
3647 				va = pv->pv_va;
3648 				pde = pmap_pde(pmap, va, &lvl);
3649 				if (lvl != 2)
3650 					continue;
3651 				pte = pmap_l2_to_l3(pde, va);
3652 				tpte = pmap_load(pte);
3653 				if ((tpte & ATTR_SW_WIRED) != 0)
3654 					continue;
3655 				if ((tpte & ATTR_CONTIGUOUS) != 0)
3656 					(void)pmap_demote_l3c(pmap, pte, va);
3657 				tpte = pmap_load_clear(pte);
3658 				m = PTE_TO_VM_PAGE(tpte);
3659 				if (pmap_pte_dirty(pmap, tpte))
3660 					vm_page_dirty(m);
3661 				if ((tpte & ATTR_AF) != 0) {
3662 					pmap_s1_invalidate_page(pmap, va, true);
3663 					vm_page_aflag_set(m, PGA_REFERENCED);
3664 				}
3665 				CHANGE_PV_LIST_LOCK_TO_VM_PAGE(lockp, m);
3666 				TAILQ_REMOVE(&m->md.pv_list, pv, pv_next);
3667 				m->md.pv_gen++;
3668 				if (!pmap_page_is_mapped_locked(m))
3669 					vm_page_aflag_clear(m, PGA_WRITEABLE);
3670 				pc->pc_map[field] |= 1UL << bit;
3671 				pmap_unuse_pt(pmap, va, pmap_load(pde), &free);
3672 				freed++;
3673 			}
3674 		}
3675 		if (freed == 0) {
3676 			mtx_lock(&pvc->pvc_lock);
3677 			goto next_chunk;
3678 		}
3679 		/* Every freed mapping is for a 4 KB page. */
3680 		pmap_resident_count_dec(pmap, freed);
3681 		PV_STAT(atomic_add_long(&pv_entry_frees, freed));
3682 		PV_STAT(atomic_add_int(&pv_entry_spare, freed));
3683 		PV_STAT(atomic_subtract_long(&pv_entry_count, freed));
3684 		TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
3685 		if (pc_is_free(pc)) {
3686 			PV_STAT(atomic_subtract_int(&pv_entry_spare, _NPCPV));
3687 			PV_STAT(atomic_subtract_int(&pc_chunk_count, 1));
3688 			PV_STAT(atomic_add_int(&pc_chunk_frees, 1));
3689 			/* Entire chunk is free; return it. */
3690 			m_pc = DMAP_TO_VM_PAGE(pc);
3691 			dump_drop_page(m_pc->phys_addr);
3692 			mtx_lock(&pvc->pvc_lock);
3693 			TAILQ_REMOVE(&pvc->pvc_list, pc, pc_lru);
3694 			break;
3695 		}
3696 		TAILQ_INSERT_HEAD(&pmap->pm_pvchunk, pc, pc_list);
3697 		mtx_lock(&pvc->pvc_lock);
3698 		/* One freed pv entry in locked_pmap is sufficient. */
3699 		if (pmap == locked_pmap)
3700 			break;
3701 
3702 next_chunk:
3703 		TAILQ_REMOVE(&pvc->pvc_list, pc_marker, pc_lru);
3704 		TAILQ_INSERT_AFTER(&pvc->pvc_list, pc, pc_marker, pc_lru);
3705 		if (pvc->active_reclaims == 1 && pmap != NULL) {
3706 			/*
3707 			 * Rotate the pv chunks list so that we do not
3708 			 * scan the same pv chunks that could not be
3709 			 * freed (because they contained a wired
3710 			 * and/or superpage mapping) on every
3711 			 * invocation of reclaim_pv_chunk().
3712 			 */
3713 			while ((pc = TAILQ_FIRST(&pvc->pvc_list)) != pc_marker){
3714 				MPASS(pc->pc_pmap != NULL);
3715 				TAILQ_REMOVE(&pvc->pvc_list, pc, pc_lru);
3716 				TAILQ_INSERT_TAIL(&pvc->pvc_list, pc, pc_lru);
3717 			}
3718 		}
3719 	}
3720 	TAILQ_REMOVE(&pvc->pvc_list, pc_marker, pc_lru);
3721 	TAILQ_REMOVE(&pvc->pvc_list, pc_marker_end, pc_lru);
3722 	pvc->active_reclaims--;
3723 	mtx_unlock(&pvc->pvc_lock);
3724 	if (pmap != NULL && pmap != locked_pmap)
3725 		PMAP_UNLOCK(pmap);
3726 	if (m_pc == NULL && !SLIST_EMPTY(&free)) {
3727 		m_pc = SLIST_FIRST(&free);
3728 		SLIST_REMOVE_HEAD(&free, plinks.s.ss);
3729 		/* Recycle a freed page table page. */
3730 		m_pc->ref_count = 1;
3731 	}
3732 	vm_page_free_pages_toq(&free, true);
3733 	return (m_pc);
3734 }
3735 
3736 static vm_page_t
3737 reclaim_pv_chunk(pmap_t locked_pmap, struct rwlock **lockp)
3738 {
3739 	vm_page_t m;
3740 	int i, domain;
3741 
3742 	domain = PCPU_GET(domain);
3743 	for (i = 0; i < vm_ndomains; i++) {
3744 		m = reclaim_pv_chunk_domain(locked_pmap, lockp, domain);
3745 		if (m != NULL)
3746 			break;
3747 		domain = (domain + 1) % vm_ndomains;
3748 	}
3749 
3750 	return (m);
3751 }
3752 
3753 /*
3754  * free the pv_entry back to the free list
3755  */
3756 static void
3757 free_pv_entry(pmap_t pmap, pv_entry_t pv)
3758 {
3759 	struct pv_chunk *pc;
3760 	int idx, field, bit;
3761 
3762 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
3763 	PV_STAT(atomic_add_long(&pv_entry_frees, 1));
3764 	PV_STAT(atomic_add_int(&pv_entry_spare, 1));
3765 	PV_STAT(atomic_subtract_long(&pv_entry_count, 1));
3766 	pc = pv_to_chunk(pv);
3767 	idx = pv - &pc->pc_pventry[0];
3768 	field = idx / 64;
3769 	bit = idx % 64;
3770 	pc->pc_map[field] |= 1ul << bit;
3771 	if (!pc_is_free(pc)) {
3772 		/* 98% of the time, pc is already at the head of the list. */
3773 		if (__predict_false(pc != TAILQ_FIRST(&pmap->pm_pvchunk))) {
3774 			TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
3775 			TAILQ_INSERT_HEAD(&pmap->pm_pvchunk, pc, pc_list);
3776 		}
3777 		return;
3778 	}
3779 	TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
3780 	free_pv_chunk(pc);
3781 }
3782 
3783 static void
3784 free_pv_chunk_dequeued(struct pv_chunk *pc)
3785 {
3786 	vm_page_t m;
3787 
3788 	PV_STAT(atomic_subtract_int(&pv_entry_spare, _NPCPV));
3789 	PV_STAT(atomic_subtract_int(&pc_chunk_count, 1));
3790 	PV_STAT(atomic_add_int(&pc_chunk_frees, 1));
3791 	/* entire chunk is free, return it */
3792 	m = DMAP_TO_VM_PAGE(pc);
3793 	dump_drop_page(m->phys_addr);
3794 	vm_page_unwire_noq(m);
3795 	vm_page_free(m);
3796 }
3797 
3798 static void
3799 free_pv_chunk(struct pv_chunk *pc)
3800 {
3801 	struct pv_chunks_list *pvc;
3802 
3803 	pvc = &pv_chunks[pc_to_domain(pc)];
3804 	mtx_lock(&pvc->pvc_lock);
3805 	TAILQ_REMOVE(&pvc->pvc_list, pc, pc_lru);
3806 	mtx_unlock(&pvc->pvc_lock);
3807 	free_pv_chunk_dequeued(pc);
3808 }
3809 
3810 static void
3811 free_pv_chunk_batch(struct pv_chunklist *batch)
3812 {
3813 	struct pv_chunks_list *pvc;
3814 	struct pv_chunk *pc, *npc;
3815 	int i;
3816 
3817 	for (i = 0; i < vm_ndomains; i++) {
3818 		if (TAILQ_EMPTY(&batch[i]))
3819 			continue;
3820 		pvc = &pv_chunks[i];
3821 		mtx_lock(&pvc->pvc_lock);
3822 		TAILQ_FOREACH(pc, &batch[i], pc_list) {
3823 			TAILQ_REMOVE(&pvc->pvc_list, pc, pc_lru);
3824 		}
3825 		mtx_unlock(&pvc->pvc_lock);
3826 	}
3827 
3828 	for (i = 0; i < vm_ndomains; i++) {
3829 		TAILQ_FOREACH_SAFE(pc, &batch[i], pc_list, npc) {
3830 			free_pv_chunk_dequeued(pc);
3831 		}
3832 	}
3833 }
3834 
3835 /*
3836  * Returns a new PV entry, allocating a new PV chunk from the system when
3837  * needed.  If this PV chunk allocation fails and a PV list lock pointer was
3838  * given, a PV chunk is reclaimed from an arbitrary pmap.  Otherwise, NULL is
3839  * returned.
3840  *
3841  * The given PV list lock may be released.
3842  */
3843 static pv_entry_t
3844 get_pv_entry(pmap_t pmap, struct rwlock **lockp)
3845 {
3846 	struct pv_chunks_list *pvc;
3847 	int bit, field;
3848 	pv_entry_t pv;
3849 	struct pv_chunk *pc;
3850 	vm_page_t m;
3851 
3852 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
3853 	PV_STAT(atomic_add_long(&pv_entry_allocs, 1));
3854 retry:
3855 	pc = TAILQ_FIRST(&pmap->pm_pvchunk);
3856 	if (pc != NULL) {
3857 		for (field = 0; field < _NPCM; field++) {
3858 			if (pc->pc_map[field]) {
3859 				bit = ffsl(pc->pc_map[field]) - 1;
3860 				break;
3861 			}
3862 		}
3863 		if (field < _NPCM) {
3864 			pv = &pc->pc_pventry[field * 64 + bit];
3865 			pc->pc_map[field] &= ~(1ul << bit);
3866 			/* If this was the last item, move it to tail */
3867 			if (pc_is_full(pc)) {
3868 				TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
3869 				TAILQ_INSERT_TAIL(&pmap->pm_pvchunk, pc,
3870 				    pc_list);
3871 			}
3872 			PV_STAT(atomic_add_long(&pv_entry_count, 1));
3873 			PV_STAT(atomic_subtract_int(&pv_entry_spare, 1));
3874 			return (pv);
3875 		}
3876 	}
3877 	/* No free items, allocate another chunk */
3878 	m = vm_page_alloc_noobj(VM_ALLOC_WIRED);
3879 	if (m == NULL) {
3880 		if (lockp == NULL) {
3881 			PV_STAT(pc_chunk_tryfail++);
3882 			return (NULL);
3883 		}
3884 		m = reclaim_pv_chunk(pmap, lockp);
3885 		if (m == NULL)
3886 			goto retry;
3887 	}
3888 	PV_STAT(atomic_add_int(&pc_chunk_count, 1));
3889 	PV_STAT(atomic_add_int(&pc_chunk_allocs, 1));
3890 	dump_add_page(m->phys_addr);
3891 	pc = PHYS_TO_DMAP(m->phys_addr);
3892 	pc->pc_pmap = pmap;
3893 	memcpy(pc->pc_map, pc_freemask, sizeof(pc_freemask));
3894 	pc->pc_map[0] &= ~1ul;		/* preallocated bit 0 */
3895 	pvc = &pv_chunks[vm_page_domain(m)];
3896 	mtx_lock(&pvc->pvc_lock);
3897 	TAILQ_INSERT_TAIL(&pvc->pvc_list, pc, pc_lru);
3898 	mtx_unlock(&pvc->pvc_lock);
3899 	pv = &pc->pc_pventry[0];
3900 	TAILQ_INSERT_HEAD(&pmap->pm_pvchunk, pc, pc_list);
3901 	PV_STAT(atomic_add_long(&pv_entry_count, 1));
3902 	PV_STAT(atomic_add_int(&pv_entry_spare, _NPCPV - 1));
3903 	return (pv);
3904 }
3905 
3906 /*
3907  * Ensure that the number of spare PV entries in the specified pmap meets or
3908  * exceeds the given count, "needed".
3909  *
3910  * The given PV list lock may be released.
3911  */
3912 static void
3913 reserve_pv_entries(pmap_t pmap, int needed, struct rwlock **lockp)
3914 {
3915 	struct pv_chunks_list *pvc;
3916 	struct pch new_tail[PMAP_MEMDOM];
3917 	struct pv_chunk *pc;
3918 	vm_page_t m;
3919 	int avail, free, i;
3920 	bool reclaimed;
3921 
3922 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
3923 	KASSERT(lockp != NULL, ("reserve_pv_entries: lockp is NULL"));
3924 
3925 	/*
3926 	 * Newly allocated PV chunks must be stored in a private list until
3927 	 * the required number of PV chunks have been allocated.  Otherwise,
3928 	 * reclaim_pv_chunk() could recycle one of these chunks.  In
3929 	 * contrast, these chunks must be added to the pmap upon allocation.
3930 	 */
3931 	for (i = 0; i < PMAP_MEMDOM; i++)
3932 		TAILQ_INIT(&new_tail[i]);
3933 retry:
3934 	avail = 0;
3935 	TAILQ_FOREACH(pc, &pmap->pm_pvchunk, pc_list) {
3936 		bit_count((bitstr_t *)pc->pc_map, 0,
3937 		    sizeof(pc->pc_map) * NBBY, &free);
3938 		if (free == 0)
3939 			break;
3940 		avail += free;
3941 		if (avail >= needed)
3942 			break;
3943 	}
3944 	for (reclaimed = false; avail < needed; avail += _NPCPV) {
3945 		m = vm_page_alloc_noobj(VM_ALLOC_WIRED);
3946 		if (m == NULL) {
3947 			m = reclaim_pv_chunk(pmap, lockp);
3948 			if (m == NULL)
3949 				goto retry;
3950 			reclaimed = true;
3951 		}
3952 		PV_STAT(atomic_add_int(&pc_chunk_count, 1));
3953 		PV_STAT(atomic_add_int(&pc_chunk_allocs, 1));
3954 		dump_add_page(m->phys_addr);
3955 		pc = PHYS_TO_DMAP(m->phys_addr);
3956 		pc->pc_pmap = pmap;
3957 		memcpy(pc->pc_map, pc_freemask, sizeof(pc_freemask));
3958 		TAILQ_INSERT_HEAD(&pmap->pm_pvchunk, pc, pc_list);
3959 		TAILQ_INSERT_TAIL(&new_tail[vm_page_domain(m)], pc, pc_lru);
3960 		PV_STAT(atomic_add_int(&pv_entry_spare, _NPCPV));
3961 
3962 		/*
3963 		 * The reclaim might have freed a chunk from the current pmap.
3964 		 * If that chunk contained available entries, we need to
3965 		 * re-count the number of available entries.
3966 		 */
3967 		if (reclaimed)
3968 			goto retry;
3969 	}
3970 	for (i = 0; i < vm_ndomains; i++) {
3971 		if (TAILQ_EMPTY(&new_tail[i]))
3972 			continue;
3973 		pvc = &pv_chunks[i];
3974 		mtx_lock(&pvc->pvc_lock);
3975 		TAILQ_CONCAT(&pvc->pvc_list, &new_tail[i], pc_lru);
3976 		mtx_unlock(&pvc->pvc_lock);
3977 	}
3978 }
3979 
3980 /*
3981  * First find and then remove the pv entry for the specified pmap and virtual
3982  * address from the specified pv list.  Returns the pv entry if found and NULL
3983  * otherwise.  This operation can be performed on pv lists for either 4KB or
3984  * 2MB page mappings.
3985  */
3986 static __inline pv_entry_t
3987 pmap_pvh_remove(struct md_page *pvh, pmap_t pmap, vm_offset_t va)
3988 {
3989 	pv_entry_t pv;
3990 
3991 	TAILQ_FOREACH(pv, &pvh->pv_list, pv_next) {
3992 		if (pmap == PV_PMAP(pv) && va == pv->pv_va) {
3993 			TAILQ_REMOVE(&pvh->pv_list, pv, pv_next);
3994 			pvh->pv_gen++;
3995 			break;
3996 		}
3997 	}
3998 	return (pv);
3999 }
4000 
4001 /*
4002  * After demotion from a 2MB page mapping to 512 4KB page mappings,
4003  * destroy the pv entry for the 2MB page mapping and reinstantiate the pv
4004  * entries for each of the 4KB page mappings.
4005  */
4006 static void
4007 pmap_pv_demote_l2(pmap_t pmap, vm_offset_t va, vm_paddr_t pa,
4008     struct rwlock **lockp)
4009 {
4010 	struct md_page *pvh;
4011 	struct pv_chunk *pc;
4012 	pv_entry_t pv;
4013 	vm_offset_t va_last;
4014 	vm_page_t m;
4015 	int bit, field;
4016 
4017 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4018 	KASSERT((va & L2_OFFSET) == 0,
4019 	    ("pmap_pv_demote_l2: va is not 2mpage aligned"));
4020 	KASSERT((pa & L2_OFFSET) == 0,
4021 	    ("pmap_pv_demote_l2: pa is not 2mpage aligned"));
4022 	CHANGE_PV_LIST_LOCK_TO_PHYS(lockp, pa);
4023 
4024 	/*
4025 	 * Transfer the 2mpage's pv entry for this mapping to the first
4026 	 * page's pv list.  Once this transfer begins, the pv list lock
4027 	 * must not be released until the last pv entry is reinstantiated.
4028 	 */
4029 	pvh = pa_to_pvh(pa);
4030 	pv = pmap_pvh_remove(pvh, pmap, va);
4031 	KASSERT(pv != NULL, ("pmap_pv_demote_l2: pv not found"));
4032 	m = PHYS_TO_VM_PAGE(pa);
4033 	TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_next);
4034 	m->md.pv_gen++;
4035 	/* Instantiate the remaining Ln_ENTRIES - 1 pv entries. */
4036 	PV_STAT(atomic_add_long(&pv_entry_allocs, Ln_ENTRIES - 1));
4037 	va_last = va + L2_SIZE - PAGE_SIZE;
4038 	for (;;) {
4039 		pc = TAILQ_FIRST(&pmap->pm_pvchunk);
4040 		KASSERT(!pc_is_full(pc), ("pmap_pv_demote_l2: missing spare"));
4041 		for (field = 0; field < _NPCM; field++) {
4042 			while (pc->pc_map[field]) {
4043 				bit = ffsl(pc->pc_map[field]) - 1;
4044 				pc->pc_map[field] &= ~(1ul << bit);
4045 				pv = &pc->pc_pventry[field * 64 + bit];
4046 				va += PAGE_SIZE;
4047 				pv->pv_va = va;
4048 				m++;
4049 				KASSERT((m->oflags & VPO_UNMANAGED) == 0,
4050 			    ("pmap_pv_demote_l2: page %p is not managed", m));
4051 				TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_next);
4052 				m->md.pv_gen++;
4053 				if (va == va_last)
4054 					goto out;
4055 			}
4056 		}
4057 		TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
4058 		TAILQ_INSERT_TAIL(&pmap->pm_pvchunk, pc, pc_list);
4059 	}
4060 out:
4061 	if (pc_is_full(pc)) {
4062 		TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
4063 		TAILQ_INSERT_TAIL(&pmap->pm_pvchunk, pc, pc_list);
4064 	}
4065 	PV_STAT(atomic_add_long(&pv_entry_count, Ln_ENTRIES - 1));
4066 	PV_STAT(atomic_subtract_int(&pv_entry_spare, Ln_ENTRIES - 1));
4067 }
4068 
4069 /*
4070  * First find and then destroy the pv entry for the specified pmap and virtual
4071  * address.  This operation can be performed on pv lists for either 4KB or 2MB
4072  * page mappings.
4073  */
4074 static void
4075 pmap_pvh_free(struct md_page *pvh, pmap_t pmap, vm_offset_t va)
4076 {
4077 	pv_entry_t pv;
4078 
4079 	pv = pmap_pvh_remove(pvh, pmap, va);
4080 	KASSERT(pv != NULL, ("pmap_pvh_free: pv not found"));
4081 	free_pv_entry(pmap, pv);
4082 }
4083 
4084 /*
4085  * Conditionally create the PV entry for a 4KB page mapping if the required
4086  * memory can be allocated without resorting to reclamation.
4087  */
4088 static bool
4089 pmap_try_insert_pv_entry(pmap_t pmap, vm_offset_t va, vm_page_t m,
4090     struct rwlock **lockp)
4091 {
4092 	pv_entry_t pv;
4093 
4094 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4095 	/* Pass NULL instead of the lock pointer to disable reclamation. */
4096 	if ((pv = get_pv_entry(pmap, NULL)) != NULL) {
4097 		pv->pv_va = va;
4098 		CHANGE_PV_LIST_LOCK_TO_VM_PAGE(lockp, m);
4099 		TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_next);
4100 		m->md.pv_gen++;
4101 		return (true);
4102 	} else
4103 		return (false);
4104 }
4105 
4106 /*
4107  * Create the PV entry for a 2MB page mapping.  Always returns true unless the
4108  * flag PMAP_ENTER_NORECLAIM is specified.  If that flag is specified, returns
4109  * false if the PV entry cannot be allocated without resorting to reclamation.
4110  */
4111 static bool
4112 pmap_pv_insert_l2(pmap_t pmap, vm_offset_t va, pd_entry_t l2e, u_int flags,
4113     struct rwlock **lockp)
4114 {
4115 	struct md_page *pvh;
4116 	pv_entry_t pv;
4117 	vm_paddr_t pa;
4118 
4119 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4120 	/* Pass NULL instead of the lock pointer to disable reclamation. */
4121 	if ((pv = get_pv_entry(pmap, (flags & PMAP_ENTER_NORECLAIM) != 0 ?
4122 	    NULL : lockp)) == NULL)
4123 		return (false);
4124 	pv->pv_va = va;
4125 	pa = PTE_TO_PHYS(l2e);
4126 	CHANGE_PV_LIST_LOCK_TO_PHYS(lockp, pa);
4127 	pvh = pa_to_pvh(pa);
4128 	TAILQ_INSERT_TAIL(&pvh->pv_list, pv, pv_next);
4129 	pvh->pv_gen++;
4130 	return (true);
4131 }
4132 
4133 /*
4134  * Conditionally creates the PV entries for a L3C superpage mapping if
4135  * the required memory can be allocated without resorting to reclamation.
4136  */
4137 static bool
4138 pmap_pv_insert_l3c(pmap_t pmap, vm_offset_t va, vm_page_t m,
4139     struct rwlock **lockp)
4140 {
4141 	pv_entry_t pv;
4142 	vm_offset_t tva;
4143 	vm_paddr_t pa __diagused;
4144 	vm_page_t mt;
4145 
4146 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4147 	KASSERT((va & L3C_OFFSET) == 0,
4148 	    ("pmap_pv_insert_l3c: va is not aligned"));
4149 	pa = VM_PAGE_TO_PHYS(m);
4150 	KASSERT((pa & L3C_OFFSET) == 0,
4151 	    ("pmap_pv_insert_l3c: pa is not aligned"));
4152 	CHANGE_PV_LIST_LOCK_TO_VM_PAGE(lockp, m);
4153 	for (mt = m, tva = va; mt < &m[L3C_ENTRIES]; mt++, tva += L3_SIZE) {
4154 		/* Pass NULL instead of lockp to disable reclamation. */
4155 		pv = get_pv_entry(pmap, NULL);
4156 		if (__predict_false(pv == NULL)) {
4157 			while (tva > va) {
4158 				mt--;
4159 				tva -= L3_SIZE;
4160 				pmap_pvh_free(&mt->md, pmap, tva);
4161 			}
4162 			return (false);
4163 		}
4164 		pv->pv_va = tva;
4165 		TAILQ_INSERT_TAIL(&mt->md.pv_list, pv, pv_next);
4166 		mt->md.pv_gen++;
4167 	}
4168 	return (true);
4169 }
4170 
4171 static void
4172 pmap_remove_kernel_l2(pmap_t pmap, pt_entry_t *l2, vm_offset_t va)
4173 {
4174 	pt_entry_t newl2, oldl2 __diagused;
4175 	vm_page_t ml3;
4176 	vm_paddr_t ml3pa;
4177 
4178 	KASSERT(!VIRT_IN_DMAP(va), ("removing direct mapping of %#lx", va));
4179 	KASSERT(pmap == kernel_pmap, ("pmap %p is not kernel_pmap", pmap));
4180 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4181 
4182 	ml3 = pmap_remove_pt_page(pmap, va);
4183 	KASSERT(ml3 != NULL, ("pmap_remove_kernel_l2: missing pt page"));
4184 
4185 	ml3pa = VM_PAGE_TO_PHYS(ml3);
4186 	newl2 = PHYS_TO_PTE(ml3pa) | L2_TABLE;
4187 
4188 	/*
4189 	 * If this page table page was unmapped by a promotion, then it
4190 	 * contains valid mappings.  Zero it to invalidate those mappings.
4191 	 */
4192 	if (vm_page_any_valid(ml3))
4193 		pagezero(PHYS_TO_DMAP(ml3pa));
4194 
4195 	/*
4196 	 * Demote the mapping.  The caller must have already invalidated the
4197 	 * mapping (i.e., the "break" in break-before-make).
4198 	 */
4199 	oldl2 = pmap_load_store(l2, newl2);
4200 	KASSERT(oldl2 == 0, ("%s: found existing mapping at %p: %#lx",
4201 	    __func__, l2, oldl2));
4202 }
4203 
4204 /*
4205  * pmap_remove_l2: Do the things to unmap a level 2 superpage.
4206  */
4207 static int
4208 pmap_remove_l2(pmap_t pmap, pt_entry_t *l2, vm_offset_t sva, pd_entry_t l1e,
4209     bool demote_kl2e, struct spglist *free, struct rwlock **lockp)
4210 {
4211 	struct md_page *pvh;
4212 	pt_entry_t old_l2;
4213 	vm_page_t m, ml3, mt;
4214 
4215 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4216 	KASSERT((sva & L2_OFFSET) == 0, ("pmap_remove_l2: sva is not aligned"));
4217 	old_l2 = pmap_load_clear(l2);
4218 	KASSERT((old_l2 & ATTR_DESCR_MASK) == L2_BLOCK,
4219 	    ("pmap_remove_l2: L2e %lx is not a block mapping", old_l2));
4220 
4221 	/*
4222 	 * Since a promotion must break the 4KB page mappings before making
4223 	 * the 2MB page mapping, a pmap_s1_invalidate_page() suffices.
4224 	 */
4225 	pmap_s1_invalidate_page(pmap, sva, true);
4226 
4227 	if (old_l2 & ATTR_SW_WIRED)
4228 		pmap->pm_stats.wired_count -= L2_SIZE / PAGE_SIZE;
4229 	pmap_resident_count_dec(pmap, L2_SIZE / PAGE_SIZE);
4230 	if (old_l2 & ATTR_SW_MANAGED) {
4231 		m = PTE_TO_VM_PAGE(old_l2);
4232 		pvh = page_to_pvh(m);
4233 		CHANGE_PV_LIST_LOCK_TO_VM_PAGE(lockp, m);
4234 		pmap_pvh_free(pvh, pmap, sva);
4235 		for (mt = m; mt < &m[L2_SIZE / PAGE_SIZE]; mt++) {
4236 			if (pmap_pte_dirty(pmap, old_l2))
4237 				vm_page_dirty(mt);
4238 			if (old_l2 & ATTR_AF)
4239 				vm_page_aflag_set(mt, PGA_REFERENCED);
4240 			if (TAILQ_EMPTY(&mt->md.pv_list) &&
4241 			    TAILQ_EMPTY(&pvh->pv_list))
4242 				vm_page_aflag_clear(mt, PGA_WRITEABLE);
4243 		}
4244 	}
4245 	if (pmap != kernel_pmap) {
4246 		ml3 = pmap_remove_pt_page(pmap, sva);
4247 		if (ml3 != NULL) {
4248 			KASSERT(vm_page_any_valid(ml3),
4249 			    ("pmap_remove_l2: l3 page not promoted"));
4250 			pmap_resident_count_dec(pmap, 1);
4251 			KASSERT(ml3->ref_count == NL3PG,
4252 			    ("pmap_remove_l2: l3 page ref count error"));
4253 			ml3->ref_count = 0;
4254 			pmap_add_delayed_free_list(ml3, free, false);
4255 		}
4256 	} else if (demote_kl2e) {
4257 		pmap_remove_kernel_l2(pmap, l2, sva);
4258 	} else {
4259 		ml3 = vm_radix_lookup(&pmap->pm_root, pmap_l2_pindex(sva));
4260 		if (vm_page_any_valid(ml3)) {
4261 			ml3->valid = 0;
4262 			pmap_zero_page(ml3);
4263 		}
4264 	}
4265 	return (pmap_unuse_pt(pmap, sva, l1e, free));
4266 }
4267 
4268 /*
4269  * pmap_remove_l3: do the things to unmap a page in a process
4270  */
4271 static int
4272 pmap_remove_l3(pmap_t pmap, pt_entry_t *l3, vm_offset_t va,
4273     pd_entry_t l2e, struct spglist *free, struct rwlock **lockp)
4274 {
4275 	pt_entry_t old_l3;
4276 	vm_page_t m;
4277 
4278 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4279 	old_l3 = pmap_load(l3);
4280 	if ((old_l3 & ATTR_CONTIGUOUS) != 0)
4281 		(void)pmap_demote_l3c(pmap, l3, va);
4282 	old_l3 = pmap_load_clear(l3);
4283 	pmap_s1_invalidate_page(pmap, va, true);
4284 	if (old_l3 & ATTR_SW_WIRED)
4285 		pmap->pm_stats.wired_count -= 1;
4286 	pmap_resident_count_dec(pmap, 1);
4287 	if (old_l3 & ATTR_SW_MANAGED) {
4288 		m = PTE_TO_VM_PAGE(old_l3);
4289 		if (pmap_pte_dirty(pmap, old_l3))
4290 			vm_page_dirty(m);
4291 		if (old_l3 & ATTR_AF)
4292 			vm_page_aflag_set(m, PGA_REFERENCED);
4293 		CHANGE_PV_LIST_LOCK_TO_VM_PAGE(lockp, m);
4294 		pmap_pvh_free(&m->md, pmap, va);
4295 		if (!pmap_page_is_mapped_locked(m))
4296 			vm_page_aflag_clear(m, PGA_WRITEABLE);
4297 	}
4298 	return (pmap_unuse_pt(pmap, va, l2e, free));
4299 }
4300 
4301 /*
4302  * Removes the specified L3C superpage mapping.  Requests TLB invalidations
4303  * to be performed by the caller through the returned "*vap". Returns true
4304  * if the level 3 table "ml3" was unmapped and added to the spglist "free".
4305  * Otherwise, returns false.
4306  */
4307 static bool
4308 pmap_remove_l3c(pmap_t pmap, pt_entry_t *l3p, vm_offset_t va, vm_offset_t *vap,
4309     vm_offset_t va_next, vm_page_t ml3, struct spglist *free,
4310     struct rwlock **lockp)
4311 {
4312 	struct md_page *pvh;
4313 	struct rwlock *new_lock;
4314 	pt_entry_t first_l3e, l3e, *tl3p;
4315 	vm_offset_t tva;
4316 	vm_page_t m, mt;
4317 
4318 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4319 	KASSERT(((uintptr_t)l3p & ((L3C_ENTRIES * sizeof(pt_entry_t)) - 1)) ==
4320 	    0, ("pmap_remove_l3c: l3p is not aligned"));
4321 	KASSERT((va & L3C_OFFSET) == 0,
4322 	    ("pmap_remove_l3c: va is not aligned"));
4323 
4324 	/*
4325 	 * Hardware accessed and dirty bit maintenance might only update a
4326 	 * single L3 entry, so we must combine the accessed and dirty bits
4327 	 * from this entire set of contiguous L3 entries.
4328 	 */
4329 	first_l3e = pmap_load_clear(l3p);
4330 	for (tl3p = l3p + 1; tl3p < &l3p[L3C_ENTRIES]; tl3p++) {
4331 		l3e = pmap_load_clear(tl3p);
4332 		KASSERT((l3e & ATTR_CONTIGUOUS) != 0,
4333 		    ("pmap_remove_l3c: l3e is missing ATTR_CONTIGUOUS"));
4334 		if ((l3e & (ATTR_SW_DBM | ATTR_S1_AP_RW_BIT)) ==
4335 		    (ATTR_SW_DBM | ATTR_S1_AP(ATTR_S1_AP_RW)))
4336 			first_l3e &= ~ATTR_S1_AP_RW_BIT;
4337 		first_l3e |= l3e & ATTR_AF;
4338 	}
4339 	if ((first_l3e & ATTR_SW_WIRED) != 0)
4340 		pmap->pm_stats.wired_count -= L3C_ENTRIES;
4341 	pmap_resident_count_dec(pmap, L3C_ENTRIES);
4342 	if ((first_l3e & ATTR_SW_MANAGED) != 0) {
4343 		m = PTE_TO_VM_PAGE(first_l3e);
4344 		new_lock = VM_PAGE_TO_PV_LIST_LOCK(m);
4345 		if (new_lock != *lockp) {
4346 			if (*lockp != NULL) {
4347 				/*
4348 				 * Pending TLB invalidations must be
4349 				 * performed before the PV list lock is
4350 				 * released.  Otherwise, a concurrent
4351 				 * pmap_remove_all() on a physical page
4352 				 * could return while a stale TLB entry
4353 				 * still provides access to that page.
4354 				 */
4355 				if (*vap != va_next) {
4356 					pmap_invalidate_range(pmap, *vap, va,
4357 					    true);
4358 					*vap = va_next;
4359 				}
4360 				rw_wunlock(*lockp);
4361 			}
4362 			*lockp = new_lock;
4363 			rw_wlock(*lockp);
4364 		}
4365 		pvh = page_to_pvh(m);
4366 		for (mt = m, tva = va; mt < &m[L3C_ENTRIES]; mt++, tva +=
4367 		    L3_SIZE) {
4368 			if (pmap_pte_dirty(pmap, first_l3e))
4369 				vm_page_dirty(mt);
4370 			if ((first_l3e & ATTR_AF) != 0)
4371 				vm_page_aflag_set(mt, PGA_REFERENCED);
4372 			pmap_pvh_free(&mt->md, pmap, tva);
4373 			if (TAILQ_EMPTY(&mt->md.pv_list) &&
4374 			    TAILQ_EMPTY(&pvh->pv_list))
4375 				vm_page_aflag_clear(mt, PGA_WRITEABLE);
4376 		}
4377 	}
4378 	if (*vap == va_next)
4379 		*vap = va;
4380 	if (ml3 != NULL) {
4381 		ml3->ref_count -= L3C_ENTRIES;
4382 		if (ml3->ref_count == 0) {
4383 			_pmap_unwire_l3(pmap, va, ml3, free);
4384 			return (true);
4385 		}
4386 	}
4387 	return (false);
4388 }
4389 
4390 /*
4391  * Remove the specified range of addresses from the L3 page table that is
4392  * identified by the given L2 entry.
4393  */
4394 static void
4395 pmap_remove_l3_range(pmap_t pmap, pd_entry_t l2e, vm_offset_t sva,
4396     vm_offset_t eva, struct spglist *free, struct rwlock **lockp)
4397 {
4398 	struct rwlock *new_lock;
4399 	pt_entry_t *l3, old_l3;
4400 	vm_offset_t va;
4401 	vm_page_t l3pg, m;
4402 
4403 	KASSERT(ADDR_IS_CANONICAL(sva),
4404 	    ("%s: Start address not in canonical form: %lx", __func__, sva));
4405 	KASSERT(ADDR_IS_CANONICAL(eva) || eva == VM_MAX_USER_ADDRESS,
4406 	    ("%s: End address not in canonical form: %lx", __func__, eva));
4407 
4408 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4409 	KASSERT(rounddown2(sva, L2_SIZE) + L2_SIZE == roundup2(eva, L2_SIZE),
4410 	    ("pmap_remove_l3_range: range crosses an L3 page table boundary"));
4411 	l3pg = ADDR_IS_USER(sva) ? PTE_TO_VM_PAGE(l2e) : NULL;
4412 	va = eva;
4413 	for (l3 = pmap_l2_to_l3(&l2e, sva); sva != eva; l3++, sva += L3_SIZE) {
4414 		old_l3 = pmap_load(l3);
4415 		if (!pmap_l3_valid(old_l3)) {
4416 			if (va != eva) {
4417 				pmap_invalidate_range(pmap, va, sva, true);
4418 				va = eva;
4419 			}
4420 			continue;
4421 		}
4422 		if ((old_l3 & ATTR_CONTIGUOUS) != 0) {
4423 			/*
4424 			 * Is this entire set of contiguous L3 entries being
4425 			 * removed?  Handle the possibility that "eva" is zero
4426 			 * because of address wraparound.
4427 			 */
4428 			if ((sva & L3C_OFFSET) == 0 &&
4429 			    sva + L3C_OFFSET <= eva - 1) {
4430 				if (pmap_remove_l3c(pmap, l3, sva, &va, eva,
4431 				    l3pg, free, lockp)) {
4432 					/* The L3 table was unmapped. */
4433 					sva += L3C_SIZE;
4434 					break;
4435 				}
4436 				l3 += L3C_ENTRIES - 1;
4437 				sva += L3C_SIZE - L3_SIZE;
4438 				continue;
4439 			}
4440 
4441 			(void)pmap_demote_l3c(pmap, l3, sva);
4442 		}
4443 		old_l3 = pmap_load_clear(l3);
4444 		if ((old_l3 & ATTR_SW_WIRED) != 0)
4445 			pmap->pm_stats.wired_count--;
4446 		pmap_resident_count_dec(pmap, 1);
4447 		/* Below will only be true in a realm environment. */
4448 		if (PTE_TO_PHYS(old_l3) & prot_ns_shared_pa)
4449 			pmap_set_protected(old_l3);
4450 		if ((old_l3 & ATTR_SW_MANAGED) != 0) {
4451 			m = PTE_TO_VM_PAGE(old_l3);
4452 			if (pmap_pte_dirty(pmap, old_l3))
4453 				vm_page_dirty(m);
4454 			if ((old_l3 & ATTR_AF) != 0)
4455 				vm_page_aflag_set(m, PGA_REFERENCED);
4456 			new_lock = VM_PAGE_TO_PV_LIST_LOCK(m);
4457 			if (new_lock != *lockp) {
4458 				if (*lockp != NULL) {
4459 					/*
4460 					 * Pending TLB invalidations must be
4461 					 * performed before the PV list lock is
4462 					 * released.  Otherwise, a concurrent
4463 					 * pmap_remove_all() on a physical page
4464 					 * could return while a stale TLB entry
4465 					 * still provides access to that page.
4466 					 */
4467 					if (va != eva) {
4468 						pmap_invalidate_range(pmap, va,
4469 						    sva, true);
4470 						va = eva;
4471 					}
4472 					rw_wunlock(*lockp);
4473 				}
4474 				*lockp = new_lock;
4475 				rw_wlock(*lockp);
4476 			}
4477 			pmap_pvh_free(&m->md, pmap, sva);
4478 			if (!pmap_page_is_mapped_locked(m))
4479 				vm_page_aflag_clear(m, PGA_WRITEABLE);
4480 		}
4481 		if (l3pg != NULL && pmap_unwire_l3(pmap, sva, l3pg, free)) {
4482 			/*
4483 			 * _pmap_unwire_l3() has already invalidated the TLB
4484 			 * entries at all levels for "sva".  So, we need not
4485 			 * perform "sva += L3_SIZE;" here.  Moreover, we need
4486 			 * not perform "va = sva;" if "sva" is at the start
4487 			 * of a new valid range consisting of a single page.
4488 			 */
4489 			break;
4490 		}
4491 		if (va == eva)
4492 			va = sva;
4493 	}
4494 	if (va != eva)
4495 		pmap_invalidate_range(pmap, va, sva, true);
4496 }
4497 
4498 static void
4499 pmap_remove1(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, bool map_delete)
4500 {
4501 	struct rwlock *lock;
4502 	vm_offset_t va_next;
4503 	pd_entry_t *l0, *l1, *l2;
4504 	pt_entry_t l3_paddr;
4505 	struct spglist free;
4506 
4507 	/*
4508 	 * Perform an unsynchronized read.  This is, however, safe.
4509 	 */
4510 	if (pmap->pm_stats.resident_count == 0)
4511 		return;
4512 
4513 	SLIST_INIT(&free);
4514 
4515 	PMAP_LOCK(pmap);
4516 	if (map_delete)
4517 		pmap_bti_on_remove(pmap, sva, eva);
4518 
4519 	lock = NULL;
4520 	for (; sva < eva; sva = va_next) {
4521 		if (pmap->pm_stats.resident_count == 0)
4522 			break;
4523 
4524 		l0 = pmap_l0(pmap, sva);
4525 		if (pmap_load(l0) == 0) {
4526 			va_next = (sva + L0_SIZE) & ~L0_OFFSET;
4527 			if (va_next < sva)
4528 				va_next = eva;
4529 			continue;
4530 		}
4531 
4532 		va_next = (sva + L1_SIZE) & ~L1_OFFSET;
4533 		if (va_next < sva)
4534 			va_next = eva;
4535 		l1 = pmap_l0_to_l1(l0, sva);
4536 		if (pmap_load(l1) == 0)
4537 			continue;
4538 		if ((pmap_load(l1) & ATTR_DESCR_MASK) == L1_BLOCK) {
4539 			PMAP_ASSERT_L1_BLOCKS_SUPPORTED;
4540 			KASSERT(va_next <= eva,
4541 			    ("partial update of non-transparent 1G page "
4542 			    "l1 %#lx sva %#lx eva %#lx va_next %#lx",
4543 			    pmap_load(l1), sva, eva, va_next));
4544 			MPASS(pmap != kernel_pmap);
4545 			MPASS((pmap_load(l1) & ATTR_SW_MANAGED) == 0);
4546 			pmap_clear(l1);
4547 			pmap_s1_invalidate_page(pmap, sva, true);
4548 			pmap_resident_count_dec(pmap, L1_SIZE / PAGE_SIZE);
4549 			pmap_unuse_pt(pmap, sva, pmap_load(l0), &free);
4550 			continue;
4551 		}
4552 
4553 		/*
4554 		 * Calculate index for next page table.
4555 		 */
4556 		va_next = (sva + L2_SIZE) & ~L2_OFFSET;
4557 		if (va_next < sva)
4558 			va_next = eva;
4559 
4560 		l2 = pmap_l1_to_l2(l1, sva);
4561 		l3_paddr = pmap_load(l2);
4562 
4563 		if ((l3_paddr & ATTR_DESCR_MASK) == L2_BLOCK) {
4564 			if (sva + L2_SIZE == va_next && eva >= va_next) {
4565 				pmap_remove_l2(pmap, l2, sva, pmap_load(l1),
4566 				    true, &free, &lock);
4567 				continue;
4568 			} else if (pmap_demote_l2_locked(pmap, l2, sva,
4569 			    &lock) == NULL)
4570 				continue;
4571 			l3_paddr = pmap_load(l2);
4572 		}
4573 
4574 		/*
4575 		 * Weed out invalid mappings.
4576 		 */
4577 		if ((l3_paddr & ATTR_DESCR_MASK) != L2_TABLE)
4578 			continue;
4579 
4580 		/*
4581 		 * Limit our scan to either the end of the va represented
4582 		 * by the current page table page, or to the end of the
4583 		 * range being removed.
4584 		 */
4585 		if (va_next > eva)
4586 			va_next = eva;
4587 
4588 		pmap_remove_l3_range(pmap, l3_paddr, sva, va_next, &free,
4589 		    &lock);
4590 	}
4591 	if (lock != NULL)
4592 		rw_wunlock(lock);
4593 	PMAP_UNLOCK(pmap);
4594 	vm_page_free_pages_toq(&free, true);
4595 }
4596 
4597 /*
4598  *	Remove the given range of addresses from the specified map.
4599  *
4600  *	It is assumed that the start and end are properly
4601  *	rounded to the page size.
4602  */
4603 void
4604 pmap_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
4605 {
4606 	pmap_remove1(pmap, sva, eva, false);
4607 }
4608 
4609 /*
4610  *	Remove the given range of addresses as part of a logical unmap
4611  *	operation. This has the effect of calling pmap_remove(), but
4612  *	also clears any metadata that should persist for the lifetime
4613  *	of a logical mapping.
4614  */
4615 void
4616 pmap_map_delete(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
4617 {
4618 	pmap_remove1(pmap, sva, eva, true);
4619 }
4620 
4621 /*
4622  *	Routine:	pmap_remove_all
4623  *	Function:
4624  *		Removes this physical page from
4625  *		all physical maps in which it resides.
4626  *		Reflects back modify bits to the pager.
4627  *
4628  *	Notes:
4629  *		Original versions of this routine were very
4630  *		inefficient because they iteratively called
4631  *		pmap_remove (slow...)
4632  */
4633 
4634 void
4635 pmap_remove_all(vm_page_t m)
4636 {
4637 	struct md_page *pvh;
4638 	pv_entry_t pv;
4639 	pmap_t pmap;
4640 	struct rwlock *lock;
4641 	pd_entry_t *pde, tpde;
4642 	pt_entry_t *pte, tpte;
4643 	vm_offset_t va;
4644 	struct spglist free;
4645 	int lvl, pvh_gen, md_gen;
4646 
4647 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
4648 	    ("pmap_remove_all: page %p is not managed", m));
4649 	SLIST_INIT(&free);
4650 	lock = VM_PAGE_TO_PV_LIST_LOCK(m);
4651 	pvh = (m->flags & PG_FICTITIOUS) != 0 ? &pv_dummy : page_to_pvh(m);
4652 	rw_wlock(lock);
4653 retry:
4654 	while ((pv = TAILQ_FIRST(&pvh->pv_list)) != NULL) {
4655 		pmap = PV_PMAP(pv);
4656 		if (!PMAP_TRYLOCK(pmap)) {
4657 			pvh_gen = pvh->pv_gen;
4658 			rw_wunlock(lock);
4659 			PMAP_LOCK(pmap);
4660 			rw_wlock(lock);
4661 			if (pvh_gen != pvh->pv_gen) {
4662 				PMAP_UNLOCK(pmap);
4663 				goto retry;
4664 			}
4665 		}
4666 		va = pv->pv_va;
4667 		pte = pmap_pte_exists(pmap, va, 2, __func__);
4668 		pmap_demote_l2_locked(pmap, pte, va, &lock);
4669 		PMAP_UNLOCK(pmap);
4670 	}
4671 	while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) {
4672 		pmap = PV_PMAP(pv);
4673 		if (!PMAP_TRYLOCK(pmap)) {
4674 			pvh_gen = pvh->pv_gen;
4675 			md_gen = m->md.pv_gen;
4676 			rw_wunlock(lock);
4677 			PMAP_LOCK(pmap);
4678 			rw_wlock(lock);
4679 			if (pvh_gen != pvh->pv_gen || md_gen != m->md.pv_gen) {
4680 				PMAP_UNLOCK(pmap);
4681 				goto retry;
4682 			}
4683 		}
4684 		pmap_resident_count_dec(pmap, 1);
4685 
4686 		pde = pmap_pde(pmap, pv->pv_va, &lvl);
4687 		KASSERT(pde != NULL,
4688 		    ("pmap_remove_all: no page directory entry found"));
4689 		KASSERT(lvl == 2,
4690 		    ("pmap_remove_all: invalid pde level %d", lvl));
4691 		tpde = pmap_load(pde);
4692 
4693 		pte = pmap_l2_to_l3(pde, pv->pv_va);
4694 		tpte = pmap_load(pte);
4695 		if ((tpte & ATTR_CONTIGUOUS) != 0)
4696 			(void)pmap_demote_l3c(pmap, pte, pv->pv_va);
4697 		tpte = pmap_load_clear(pte);
4698 		if (tpte & ATTR_SW_WIRED)
4699 			pmap->pm_stats.wired_count--;
4700 		if ((tpte & ATTR_AF) != 0) {
4701 			pmap_invalidate_page(pmap, pv->pv_va, true);
4702 			vm_page_aflag_set(m, PGA_REFERENCED);
4703 		}
4704 
4705 		/*
4706 		 * Update the vm_page_t clean and reference bits.
4707 		 */
4708 		if (pmap_pte_dirty(pmap, tpte))
4709 			vm_page_dirty(m);
4710 		pmap_unuse_pt(pmap, pv->pv_va, tpde, &free);
4711 		TAILQ_REMOVE(&m->md.pv_list, pv, pv_next);
4712 		m->md.pv_gen++;
4713 		free_pv_entry(pmap, pv);
4714 		PMAP_UNLOCK(pmap);
4715 	}
4716 	vm_page_aflag_clear(m, PGA_WRITEABLE);
4717 	rw_wunlock(lock);
4718 	vm_page_free_pages_toq(&free, true);
4719 }
4720 
4721 /*
4722  * Masks and sets bits in a level 2 page table entries in the specified pmap
4723  */
4724 static void
4725 pmap_protect_l2(pmap_t pmap, pt_entry_t *l2, vm_offset_t sva, pt_entry_t mask,
4726     pt_entry_t nbits)
4727 {
4728 	pd_entry_t old_l2;
4729 	vm_page_t m, mt;
4730 
4731 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4732 	PMAP_ASSERT_STAGE1(pmap);
4733 	KASSERT((sva & L2_OFFSET) == 0,
4734 	    ("pmap_protect_l2: sva is not 2mpage aligned"));
4735 	old_l2 = pmap_load(l2);
4736 	KASSERT((old_l2 & ATTR_DESCR_MASK) == L2_BLOCK,
4737 	    ("pmap_protect_l2: L2e %lx is not a block mapping", old_l2));
4738 
4739 	/*
4740 	 * Return if the L2 entry already has the desired access restrictions
4741 	 * in place.
4742 	 */
4743 	if ((old_l2 & mask) == nbits)
4744 		return;
4745 
4746 	while (!atomic_fcmpset_64(l2, &old_l2, (old_l2 & ~mask) | nbits))
4747 		cpu_spinwait();
4748 
4749 	/*
4750 	 * When a dirty read/write superpage mapping is write protected,
4751 	 * update the dirty field of each of the superpage's constituent 4KB
4752 	 * pages.
4753 	 */
4754 	if ((old_l2 & ATTR_SW_MANAGED) != 0 &&
4755 	    (nbits & ATTR_S1_AP(ATTR_S1_AP_RO)) != 0 &&
4756 	    pmap_pte_dirty(pmap, old_l2)) {
4757 		m = PTE_TO_VM_PAGE(old_l2);
4758 		for (mt = m; mt < &m[L2_SIZE / PAGE_SIZE]; mt++)
4759 			vm_page_dirty(mt);
4760 	}
4761 
4762 	/*
4763 	 * Since a promotion must break the 4KB page mappings before making
4764 	 * the 2MB page mapping, a pmap_s1_invalidate_page() suffices.
4765 	 */
4766 	pmap_s1_invalidate_page(pmap, sva, true);
4767 }
4768 
4769 /*
4770  * Masks and sets bits in the specified L3C superpage mapping.
4771  *
4772  * Requests TLB invalidations to be performed by the caller through the
4773  * returned "*vap".
4774  */
4775 static void
4776 pmap_mask_set_l3c(pmap_t pmap, pt_entry_t *l3p, vm_offset_t va,
4777     vm_offset_t *vap, vm_offset_t va_next, pt_entry_t mask, pt_entry_t nbits)
4778 {
4779 	pt_entry_t l3e, *tl3p;
4780 	vm_page_t m, mt;
4781 	bool dirty;
4782 
4783 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4784 	KASSERT(((uintptr_t)l3p & ((L3C_ENTRIES * sizeof(pt_entry_t)) - 1)) ==
4785 	    0, ("pmap_mask_set_l3c: l3p is not aligned"));
4786 	KASSERT((va & L3C_OFFSET) == 0,
4787 	    ("pmap_mask_set_l3c: va is not aligned"));
4788 	dirty = false;
4789 	for (tl3p = l3p; tl3p < &l3p[L3C_ENTRIES]; tl3p++) {
4790 		l3e = pmap_load(tl3p);
4791 		KASSERT((l3e & ATTR_CONTIGUOUS) != 0,
4792 		    ("pmap_mask_set_l3c: l3e is missing ATTR_CONTIGUOUS"));
4793 		while (!atomic_fcmpset_64(tl3p, &l3e, (l3e & ~mask) | nbits))
4794 			cpu_spinwait();
4795 		if ((l3e & (ATTR_SW_DBM | ATTR_S1_AP_RW_BIT)) ==
4796 		    (ATTR_SW_DBM | ATTR_S1_AP(ATTR_S1_AP_RW)))
4797 			dirty = true;
4798 	}
4799 
4800 	/*
4801 	 * When a dirty read/write superpage mapping is write protected,
4802 	 * update the dirty field of each of the superpage's constituent 4KB
4803 	 * pages.
4804 	 */
4805 	if ((l3e & ATTR_SW_MANAGED) != 0 &&
4806 	    (nbits & ATTR_S1_AP(ATTR_S1_AP_RO)) != 0 &&
4807 	    dirty) {
4808 		m = PTE_TO_VM_PAGE(pmap_load(l3p));
4809 		for (mt = m; mt < &m[L3C_ENTRIES]; mt++)
4810 			vm_page_dirty(mt);
4811 	}
4812 
4813 	if (*vap == va_next)
4814 		*vap = va;
4815 }
4816 
4817 /*
4818  * Masks and sets bits in last level page table entries in the specified
4819  * pmap and range
4820  */
4821 static void
4822 pmap_mask_set_locked(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, pt_entry_t mask,
4823     pt_entry_t nbits, bool invalidate)
4824 {
4825 	vm_offset_t va, va_next;
4826 	pd_entry_t *l0, *l1, *l2;
4827 	pt_entry_t *l3p, l3;
4828 
4829 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4830 	for (; sva < eva; sva = va_next) {
4831 		l0 = pmap_l0(pmap, sva);
4832 		if (pmap_load(l0) == 0) {
4833 			va_next = (sva + L0_SIZE) & ~L0_OFFSET;
4834 			if (va_next < sva)
4835 				va_next = eva;
4836 			continue;
4837 		}
4838 
4839 		va_next = (sva + L1_SIZE) & ~L1_OFFSET;
4840 		if (va_next < sva)
4841 			va_next = eva;
4842 		l1 = pmap_l0_to_l1(l0, sva);
4843 		if (pmap_load(l1) == 0)
4844 			continue;
4845 		if ((pmap_load(l1) & ATTR_DESCR_MASK) == L1_BLOCK) {
4846 			PMAP_ASSERT_L1_BLOCKS_SUPPORTED;
4847 			KASSERT(va_next <= eva,
4848 			    ("partial update of non-transparent 1G page "
4849 			    "l1 %#lx sva %#lx eva %#lx va_next %#lx",
4850 			    pmap_load(l1), sva, eva, va_next));
4851 			MPASS((pmap_load(l1) & ATTR_SW_MANAGED) == 0);
4852 			if ((pmap_load(l1) & mask) != nbits) {
4853 				pmap_store(l1, (pmap_load(l1) & ~mask) | nbits);
4854 				if (invalidate)
4855 					pmap_s1_invalidate_page(pmap, sva, true);
4856 			}
4857 			continue;
4858 		}
4859 
4860 		va_next = (sva + L2_SIZE) & ~L2_OFFSET;
4861 		if (va_next < sva)
4862 			va_next = eva;
4863 
4864 		l2 = pmap_l1_to_l2(l1, sva);
4865 		if (pmap_load(l2) == 0)
4866 			continue;
4867 
4868 		if ((pmap_load(l2) & ATTR_DESCR_MASK) == L2_BLOCK) {
4869 			if (sva + L2_SIZE == va_next && eva >= va_next) {
4870 				pmap_protect_l2(pmap, l2, sva, mask, nbits);
4871 				continue;
4872 			} else if ((pmap_load(l2) & mask) == nbits ||
4873 			    pmap_demote_l2(pmap, l2, sva) == NULL)
4874 				continue;
4875 		}
4876 		KASSERT((pmap_load(l2) & ATTR_DESCR_MASK) == L2_TABLE,
4877 		    ("pmap_protect: Invalid L2 entry after demotion"));
4878 
4879 		if (va_next > eva)
4880 			va_next = eva;
4881 
4882 		va = va_next;
4883 		for (l3p = pmap_l2_to_l3(l2, sva); sva != va_next; l3p++,
4884 		    sva += L3_SIZE) {
4885 			l3 = pmap_load(l3p);
4886 
4887 			/*
4888 			 * Go to the next L3 entry if the current one is
4889 			 * invalid or already has the desired access
4890 			 * restrictions in place.  (The latter case occurs
4891 			 * frequently.  For example, in a "buildworld"
4892 			 * workload, almost 1 out of 4 L3 entries already
4893 			 * have the desired restrictions.)
4894 			 */
4895 			if (!pmap_l3_valid(l3) || (l3 & mask) == nbits) {
4896 				if (va != va_next) {
4897 					if (invalidate)
4898 						pmap_s1_invalidate_range(pmap,
4899 						    va, sva, true);
4900 					va = va_next;
4901 				}
4902 				if ((l3 & ATTR_CONTIGUOUS) != 0) {
4903 					/*
4904 					 * Does this L3C page extend beyond
4905 					 * the requested range?  Handle the
4906 					 * possibility that "va_next" is zero.
4907 					 */
4908 					if ((sva | L3C_OFFSET) > va_next - 1)
4909 						break;
4910 
4911 					/*
4912 					 * Skip ahead to the last L3_PAGE
4913 					 * within this L3C page.
4914 					 */
4915 					l3p = (pt_entry_t *)((uintptr_t)l3p |
4916 					    ((L3C_ENTRIES - 1) *
4917 					    sizeof(pt_entry_t)));
4918 					sva |= L3C_SIZE - L3_SIZE;
4919 				}
4920 				continue;
4921 			}
4922 
4923 			if ((l3 & ATTR_CONTIGUOUS) != 0) {
4924 				/*
4925 				 * Is this entire set of contiguous L3 entries
4926 				 * being protected?  Handle the possibility
4927 				 * that "va_next" is zero because of address
4928 				 * wraparound.
4929 				 */
4930 				if ((sva & L3C_OFFSET) == 0 &&
4931 				    sva + L3C_OFFSET <= va_next - 1) {
4932 					pmap_mask_set_l3c(pmap, l3p, sva, &va,
4933 					    va_next, mask, nbits);
4934 					l3p += L3C_ENTRIES - 1;
4935 					sva += L3C_SIZE - L3_SIZE;
4936 					continue;
4937 				}
4938 
4939 				(void)pmap_demote_l3c(pmap, l3p, sva);
4940 
4941 				/*
4942 				 * The L3 entry's accessed bit may have changed.
4943 				 */
4944 				l3 = pmap_load(l3p);
4945 			}
4946 			while (!atomic_fcmpset_64(l3p, &l3, (l3 & ~mask) |
4947 			    nbits))
4948 				cpu_spinwait();
4949 
4950 			/*
4951 			 * When a dirty read/write mapping is write protected,
4952 			 * update the page's dirty field.
4953 			 */
4954 			if ((l3 & ATTR_SW_MANAGED) != 0 &&
4955 			    (nbits & ATTR_S1_AP(ATTR_S1_AP_RO)) != 0 &&
4956 			    pmap_pte_dirty(pmap, l3))
4957 				vm_page_dirty(PTE_TO_VM_PAGE(l3));
4958 
4959 			if (va == va_next)
4960 				va = sva;
4961 		}
4962 		if (va != va_next && invalidate)
4963 			pmap_s1_invalidate_range(pmap, va, sva, true);
4964 	}
4965 }
4966 
4967 static void
4968 pmap_mask_set(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, pt_entry_t mask,
4969     pt_entry_t nbits, bool invalidate)
4970 {
4971 	PMAP_LOCK(pmap);
4972 	pmap_mask_set_locked(pmap, sva, eva, mask, nbits, invalidate);
4973 	PMAP_UNLOCK(pmap);
4974 }
4975 
4976 /*
4977  *	Set the physical protection on the
4978  *	specified range of this map as requested.
4979  */
4980 void
4981 pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot)
4982 {
4983 	pt_entry_t mask, nbits;
4984 
4985 	PMAP_ASSERT_STAGE1(pmap);
4986 	KASSERT((prot & ~VM_PROT_ALL) == 0, ("invalid prot %x", prot));
4987 	if (prot == VM_PROT_NONE) {
4988 		pmap_remove(pmap, sva, eva);
4989 		return;
4990 	}
4991 
4992 	mask = nbits = 0;
4993 	if ((prot & VM_PROT_WRITE) == 0) {
4994 		mask |= ATTR_S1_AP_RW_BIT | ATTR_SW_DBM;
4995 		nbits |= ATTR_S1_AP(ATTR_S1_AP_RO);
4996 	}
4997 	if ((prot & VM_PROT_EXECUTE) == 0) {
4998 		mask |= ATTR_S1_XN;
4999 		nbits |= ATTR_S1_XN;
5000 	}
5001 	if (pmap == kernel_pmap) {
5002 		mask |= ATTR_KERN_GP;
5003 		nbits |= ATTR_KERN_GP;
5004 	}
5005 	if (mask == 0)
5006 		return;
5007 
5008 	pmap_mask_set(pmap, sva, eva, mask, nbits, true);
5009 }
5010 
5011 void
5012 pmap_disable_promotion(vm_offset_t sva, vm_size_t size)
5013 {
5014 
5015 	MPASS((sva & L3_OFFSET) == 0);
5016 	MPASS(((sva + size) & L3_OFFSET) == 0);
5017 
5018 	pmap_mask_set(kernel_pmap, sva, sva + size, ATTR_SW_NO_PROMOTE,
5019 	    ATTR_SW_NO_PROMOTE, false);
5020 }
5021 
5022 /*
5023  * Inserts the specified page table page into the specified pmap's collection
5024  * of idle page table pages.  Each of a pmap's page table pages is responsible
5025  * for mapping a distinct range of virtual addresses.  The pmap's collection is
5026  * ordered by this virtual address range.
5027  *
5028  * If "promoted" is false, then the page table page "mpte" must be zero filled;
5029  * "mpte"'s valid field will be set to 0.
5030  *
5031  * If "promoted" is true and "all_l3e_AF_set" is false, then "mpte" must
5032  * contain valid mappings with identical attributes except for ATTR_AF;
5033  * "mpte"'s valid field will be set to 1.
5034  *
5035  * If "promoted" and "all_l3e_AF_set" are both true, then "mpte" must contain
5036  * valid mappings with identical attributes including ATTR_AF; "mpte"'s valid
5037  * field will be set to VM_PAGE_BITS_ALL.
5038  */
5039 static __inline int
5040 pmap_insert_pt_page(pmap_t pmap, vm_page_t mpte, bool promoted,
5041     bool all_l3e_AF_set)
5042 {
5043 
5044 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
5045 	KASSERT(promoted || !all_l3e_AF_set,
5046 	    ("a zero-filled PTP can't have ATTR_AF set in every PTE"));
5047 	mpte->valid = promoted ? (all_l3e_AF_set ? VM_PAGE_BITS_ALL : 1) : 0;
5048 	return (vm_radix_insert(&pmap->pm_root, mpte));
5049 }
5050 
5051 /*
5052  * Removes the page table page mapping the specified virtual address from the
5053  * specified pmap's collection of idle page table pages, and returns it.
5054  * Otherwise, returns NULL if there is no page table page corresponding to the
5055  * specified virtual address.
5056  */
5057 static __inline vm_page_t
5058 pmap_remove_pt_page(pmap_t pmap, vm_offset_t va)
5059 {
5060 
5061 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
5062 	return (vm_radix_remove(&pmap->pm_root, pmap_l2_pindex(va)));
5063 }
5064 
5065 /*
5066  * Performs a break-before-make update of a pmap entry. This is needed when
5067  * either promoting or demoting pages to ensure the TLB doesn't get into an
5068  * inconsistent state.  The caller must pass false for "final_only" when
5069  * promoting, because the TLB might be caching an intermediate entry that
5070  * references the L{1,2}_TABLE that is being replaced.  In contrast, when
5071  * demoting or the PTE's type isn't changing, no cached intermediate entry
5072  * needs to change, so the caller should pass true as an optimization.
5073  */
5074 static __always_inline void
5075 pmap_update_entry(pmap_t pmap, pd_entry_t *ptep, pd_entry_t newpte,
5076     vm_offset_t va, vm_size_t size, bool final_only)
5077 {
5078 	register_t intr;
5079 
5080 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
5081 	KASSERT((newpte & ATTR_SW_NO_PROMOTE) == 0,
5082 	    ("%s: Updating non-promote pte", __func__));
5083 
5084 	/*
5085 	 * Ensure we don't get switched out with the page table in an
5086 	 * inconsistent state. We also need to ensure no interrupts fire
5087 	 * as they may make use of an address we are about to invalidate.
5088 	 */
5089 	intr = intr_disable();
5090 
5091 	/*
5092 	 * Clear the old mapping's valid bit, but leave the rest of the entry
5093 	 * unchanged, so that a lockless, concurrent pmap_kextract() can still
5094 	 * lookup the physical address.
5095 	 */
5096 	pmap_clear_bits(ptep, ATTR_DESCR_VALID);
5097 
5098 	/*
5099 	 * We always inline pmap_update_entry() so that constant propagation
5100 	 * and dead code elimination will specialize the following code.
5101 	 */
5102 	pmap_s1_invalidate_range(pmap, va, va + size, final_only);
5103 
5104 	/* Create the new mapping */
5105 	pmap_store(ptep, newpte);
5106 	dsb(ishst);
5107 
5108 	intr_restore(intr);
5109 }
5110 
5111 /*
5112  * Performs a break-before-make update of an ATTR_CONTIGUOUS mapping.
5113  */
5114 static void __nosanitizecoverage
5115 pmap_update_strided(pmap_t pmap, pd_entry_t *ptep, pd_entry_t *ptep_end,
5116     pd_entry_t newpte, vm_offset_t va, vm_offset_t stride, vm_size_t size)
5117 {
5118 	pd_entry_t *lip;
5119 	register_t intr;
5120 
5121 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
5122 	KASSERT((newpte & ATTR_SW_NO_PROMOTE) == 0,
5123 	    ("%s: Updating non-promote pte", __func__));
5124 
5125 	/*
5126 	 * Ensure we don't get switched out with the page table in an
5127 	 * inconsistent state. We also need to ensure no interrupts fire
5128 	 * as they may make use of an address we are about to invalidate.
5129 	 */
5130 	intr = intr_disable();
5131 
5132 	/*
5133 	 * Clear the old mapping's valid bits, but leave the rest of each
5134 	 * entry unchanged, so that a lockless, concurrent pmap_kextract() can
5135 	 * still lookup the physical address.
5136 	 */
5137 	for (lip = ptep; lip < ptep_end; lip++)
5138 		pmap_clear_bits(lip, ATTR_DESCR_VALID);
5139 
5140 	/* Only final entries are changing. */
5141 	pmap_s1_invalidate_strided(pmap, va, va + size, stride, true);
5142 
5143 	/* Create the new mapping. */
5144 	for (lip = ptep; lip < ptep_end; lip++) {
5145 		pmap_store(lip, newpte);
5146 		newpte += stride;
5147 	}
5148 	dsb(ishst);
5149 
5150 	intr_restore(intr);
5151 }
5152 
5153 #if VM_NRESERVLEVEL > 0
5154 /*
5155  * After promotion from 512 4KB page mappings to a single 2MB page mapping,
5156  * replace the many pv entries for the 4KB page mappings by a single pv entry
5157  * for the 2MB page mapping.
5158  */
5159 static void
5160 pmap_pv_promote_l2(pmap_t pmap, vm_offset_t va, vm_paddr_t pa,
5161     struct rwlock **lockp)
5162 {
5163 	struct md_page *pvh;
5164 	pv_entry_t pv;
5165 	vm_offset_t va_last;
5166 	vm_page_t m;
5167 
5168 	KASSERT((pa & L2_OFFSET) == 0,
5169 	    ("pmap_pv_promote_l2: pa is not 2mpage aligned"));
5170 	CHANGE_PV_LIST_LOCK_TO_PHYS(lockp, pa);
5171 
5172 	/*
5173 	 * Transfer the first page's pv entry for this mapping to the 2mpage's
5174 	 * pv list.  Aside from avoiding the cost of a call to get_pv_entry(),
5175 	 * a transfer avoids the possibility that get_pv_entry() calls
5176 	 * reclaim_pv_chunk() and that reclaim_pv_chunk() removes one of the
5177 	 * mappings that is being promoted.
5178 	 */
5179 	m = PHYS_TO_VM_PAGE(pa);
5180 	va = va & ~L2_OFFSET;
5181 	pv = pmap_pvh_remove(&m->md, pmap, va);
5182 	KASSERT(pv != NULL, ("pmap_pv_promote_l2: pv not found"));
5183 	pvh = page_to_pvh(m);
5184 	TAILQ_INSERT_TAIL(&pvh->pv_list, pv, pv_next);
5185 	pvh->pv_gen++;
5186 	/* Free the remaining NPTEPG - 1 pv entries. */
5187 	va_last = va + L2_SIZE - PAGE_SIZE;
5188 	do {
5189 		m++;
5190 		va += PAGE_SIZE;
5191 		pmap_pvh_free(&m->md, pmap, va);
5192 	} while (va < va_last);
5193 }
5194 
5195 /*
5196  * Tries to promote the 512, contiguous 4KB page mappings that are within a
5197  * single level 2 table entry to a single 2MB page mapping.  For promotion
5198  * to occur, two conditions must be met: (1) the 4KB page mappings must map
5199  * aligned, contiguous physical memory and (2) the 4KB page mappings must have
5200  * identical characteristics.
5201  */
5202 static bool
5203 pmap_promote_l2(pmap_t pmap, pd_entry_t *l2, vm_offset_t va, vm_page_t mpte,
5204     struct rwlock **lockp)
5205 {
5206 	pt_entry_t all_l3e_AF, *firstl3, *l3, newl2, oldl3, pa;
5207 
5208 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
5209 
5210 	/*
5211 	 * Currently, this function only supports promotion on stage 1 pmaps
5212 	 * because it tests stage 1 specific fields and performs a break-
5213 	 * before-make sequence that is incorrect for stage 2 pmaps.
5214 	 */
5215 	if (pmap->pm_stage != PM_STAGE1 || !pmap_ps_enabled(pmap))
5216 		return (false);
5217 
5218 	/*
5219 	 * Examine the first L3E in the specified PTP.  Abort if this L3E is
5220 	 * ineligible for promotion...
5221 	 */
5222 	firstl3 = PHYS_TO_DMAP(PTE_TO_PHYS(pmap_load(l2)));
5223 	newl2 = pmap_load(firstl3);
5224 	if ((newl2 & ATTR_SW_NO_PROMOTE) != 0)
5225 		return (false);
5226 	/* ... is not the first physical page within an L2 block */
5227 	if ((PTE_TO_PHYS(newl2) & L2_OFFSET) != 0 ||
5228 	    ((newl2 & ATTR_DESCR_MASK) != L3_PAGE)) { /* ... or is invalid */
5229 		counter_u64_add(pmap_l2_p_failures, 1);
5230 		CTR2(KTR_PMAP, "pmap_promote_l2: failure for va %#lx"
5231 		    " in pmap %p", va, pmap);
5232 		return (false);
5233 	}
5234 
5235 	/*
5236 	 * Both here and in the below "for" loop, to allow for repromotion
5237 	 * after MADV_FREE, conditionally write protect a clean L3E before
5238 	 * possibly aborting the promotion due to other L3E attributes.  Why?
5239 	 * Suppose that MADV_FREE is applied to a part of a superpage, the
5240 	 * address range [S, E).  pmap_advise() will demote the superpage
5241 	 * mapping, destroy the 4KB page mapping at the end of [S, E), and
5242 	 * set AP_RO and clear AF in the L3Es for the rest of [S, E).  Later,
5243 	 * imagine that the memory in [S, E) is recycled, but the last 4KB
5244 	 * page in [S, E) is not the last to be rewritten, or simply accessed.
5245 	 * In other words, there is still a 4KB page in [S, E), call it P,
5246 	 * that is writeable but AP_RO is set and AF is clear in P's L3E.
5247 	 * Unless we write protect P before aborting the promotion, if and
5248 	 * when P is finally rewritten, there won't be a page fault to trigger
5249 	 * repromotion.
5250 	 */
5251 setl2:
5252 	if ((newl2 & (ATTR_S1_AP_RW_BIT | ATTR_SW_DBM)) ==
5253 	    (ATTR_S1_AP(ATTR_S1_AP_RO) | ATTR_SW_DBM)) {
5254 		/*
5255 		 * When the mapping is clean, i.e., ATTR_S1_AP_RO is set,
5256 		 * ATTR_SW_DBM can be cleared without a TLB invalidation.
5257 		 */
5258 		if (!atomic_fcmpset_64(firstl3, &newl2, newl2 & ~ATTR_SW_DBM))
5259 			goto setl2;
5260 		newl2 &= ~ATTR_SW_DBM;
5261 		CTR2(KTR_PMAP, "pmap_promote_l2: protect for va %#lx"
5262 		    " in pmap %p", va & ~L2_OFFSET, pmap);
5263 	}
5264 
5265 	/*
5266 	 * Examine each of the other L3Es in the specified PTP.  Abort if this
5267 	 * L3E maps an unexpected 4KB physical page or does not have identical
5268 	 * characteristics to the first L3E.  If ATTR_AF is not set in every
5269 	 * PTE, then request that the PTP be refilled on demotion.
5270 	 */
5271 	all_l3e_AF = newl2 & ATTR_AF;
5272 	pa = (PTE_TO_PHYS(newl2) | (newl2 & ATTR_DESCR_MASK))
5273 	    + L2_SIZE - PAGE_SIZE;
5274 	for (l3 = firstl3 + NL3PG - 1; l3 > firstl3; l3--) {
5275 		oldl3 = pmap_load(l3);
5276 		if ((PTE_TO_PHYS(oldl3) | (oldl3 & ATTR_DESCR_MASK)) != pa) {
5277 			counter_u64_add(pmap_l2_p_failures, 1);
5278 			CTR2(KTR_PMAP, "pmap_promote_l2: failure for va %#lx"
5279 			    " in pmap %p", va, pmap);
5280 			return (false);
5281 		}
5282 setl3:
5283 		if ((oldl3 & (ATTR_S1_AP_RW_BIT | ATTR_SW_DBM)) ==
5284 		    (ATTR_S1_AP(ATTR_S1_AP_RO) | ATTR_SW_DBM)) {
5285 			/*
5286 			 * When the mapping is clean, i.e., ATTR_S1_AP_RO is
5287 			 * set, ATTR_SW_DBM can be cleared without a TLB
5288 			 * invalidation.
5289 			 */
5290 			if (!atomic_fcmpset_64(l3, &oldl3, oldl3 &
5291 			    ~ATTR_SW_DBM))
5292 				goto setl3;
5293 			oldl3 &= ~ATTR_SW_DBM;
5294 		}
5295 		if ((oldl3 & ATTR_PROMOTE) != (newl2 & ATTR_PROMOTE)) {
5296 			counter_u64_add(pmap_l2_p_failures, 1);
5297 			CTR2(KTR_PMAP, "pmap_promote_l2: failure for va %#lx"
5298 			    " in pmap %p", va, pmap);
5299 			return (false);
5300 		}
5301 		all_l3e_AF &= oldl3;
5302 		pa -= PAGE_SIZE;
5303 	}
5304 
5305 	/*
5306 	 * Unless all PTEs have ATTR_AF set, clear it from the superpage
5307 	 * mapping, so that promotions triggered by speculative mappings,
5308 	 * such as pmap_enter_quick(), don't automatically mark the
5309 	 * underlying pages as referenced.
5310 	 */
5311 	newl2 &= ~(ATTR_CONTIGUOUS | ATTR_AF | ATTR_DESCR_MASK) | all_l3e_AF;
5312 
5313 	/*
5314 	 * Save the page table page in its current state until the L2
5315 	 * mapping the superpage is demoted by pmap_demote_l2() or
5316 	 * destroyed by pmap_remove_l3().
5317 	 */
5318 	if (mpte == NULL)
5319 		mpte = PTE_TO_VM_PAGE(pmap_load(l2));
5320 	KASSERT(mpte >= vm_page_array &&
5321 	    mpte < &vm_page_array[vm_page_array_size],
5322 	    ("pmap_promote_l2: page table page is out of range"));
5323 	KASSERT(mpte->pindex == pmap_l2_pindex(va),
5324 	    ("pmap_promote_l2: page table page's pindex is wrong"));
5325 	if (pmap_insert_pt_page(pmap, mpte, true, all_l3e_AF != 0)) {
5326 		counter_u64_add(pmap_l2_p_failures, 1);
5327 		CTR2(KTR_PMAP,
5328 		    "pmap_promote_l2: failure for va %#lx in pmap %p", va,
5329 		    pmap);
5330 		return (false);
5331 	}
5332 
5333 	if ((newl2 & ATTR_SW_MANAGED) != 0)
5334 		pmap_pv_promote_l2(pmap, va, PTE_TO_PHYS(newl2), lockp);
5335 
5336 	pmap_update_entry(pmap, l2, newl2 | L2_BLOCK, va & ~L2_OFFSET, L2_SIZE,
5337 	    false);
5338 
5339 	counter_u64_add(pmap_l2_promotions, 1);
5340 	CTR2(KTR_PMAP, "pmap_promote_l2: success for va %#lx in pmap %p", va,
5341 	    pmap);
5342 	return (true);
5343 }
5344 
5345 /*
5346  * Tries to promote an aligned, contiguous set of base page mappings to a
5347  * single L3C page mapping.  For promotion to occur, two conditions must be
5348  * met: (1) the base page mappings must map aligned, contiguous physical
5349  * memory and (2) the base page mappings must have identical characteristics
5350  * except for the accessed flag.
5351  */
5352 static bool
5353 pmap_promote_l3c(pmap_t pmap, pd_entry_t *l3p, vm_offset_t va)
5354 {
5355 	pd_entry_t all_l3e_AF, firstl3c, *l3, oldl3, pa;
5356 
5357 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
5358 
5359 	/*
5360 	 * Currently, this function only supports promotion on stage 1 pmaps
5361 	 * because it tests stage 1 specific fields and performs a break-
5362 	 * before-make sequence that is incorrect for stage 2 pmaps.
5363 	 */
5364 	if (pmap->pm_stage != PM_STAGE1 || !pmap_ps_enabled(pmap))
5365 		return (false);
5366 
5367 	/*
5368 	 * Compute the address of the first L3 entry in the superpage
5369 	 * candidate.
5370 	 */
5371 	l3p = (pt_entry_t *)((uintptr_t)l3p & ~((L3C_ENTRIES *
5372 	    sizeof(pt_entry_t)) - 1));
5373 
5374 	firstl3c = pmap_load(l3p);
5375 
5376 	/*
5377 	 * Examine the first L3 entry. Abort if this L3E is ineligible for
5378 	 * promotion...
5379 	 */
5380 	if ((firstl3c & ATTR_SW_NO_PROMOTE) != 0)
5381 		return (false);
5382 	/* ...is not properly aligned... */
5383 	if ((PTE_TO_PHYS(firstl3c) & L3C_OFFSET) != 0 ||
5384 	    (firstl3c & ATTR_DESCR_MASK) != L3_PAGE) { /* ...or is invalid. */
5385 		counter_u64_add(pmap_l3c_p_failures, 1);
5386 		CTR2(KTR_PMAP, "pmap_promote_l3c: failure for va %#lx"
5387 		    " in pmap %p", va, pmap);
5388 		return (false);
5389 	}
5390 
5391 	/*
5392 	 * If the first L3 entry is a clean read-write mapping, convert it
5393 	 * to a read-only mapping.  See pmap_promote_l2() for the rationale.
5394 	 */
5395 set_first:
5396 	if ((firstl3c & (ATTR_S1_AP_RW_BIT | ATTR_SW_DBM)) ==
5397 	    (ATTR_S1_AP(ATTR_S1_AP_RO) | ATTR_SW_DBM)) {
5398 		/*
5399 		 * When the mapping is clean, i.e., ATTR_S1_AP_RO is set,
5400 		 * ATTR_SW_DBM can be cleared without a TLB invalidation.
5401 		 */
5402 		if (!atomic_fcmpset_64(l3p, &firstl3c, firstl3c & ~ATTR_SW_DBM))
5403 			goto set_first;
5404 		firstl3c &= ~ATTR_SW_DBM;
5405 		CTR2(KTR_PMAP, "pmap_promote_l3c: protect for va %#lx"
5406 		    " in pmap %p", va & ~L3C_OFFSET, pmap);
5407 	}
5408 
5409 	/*
5410 	 * Check that the rest of the L3 entries are compatible with the first,
5411 	 * and convert clean read-write mappings to read-only mappings.
5412 	 */
5413 	all_l3e_AF = firstl3c & ATTR_AF;
5414 	pa = (PTE_TO_PHYS(firstl3c) | (firstl3c & ATTR_DESCR_MASK)) +
5415 	    L3C_SIZE - PAGE_SIZE;
5416 	for (l3 = l3p + L3C_ENTRIES - 1; l3 > l3p; l3--) {
5417 		oldl3 = pmap_load(l3);
5418 		if ((PTE_TO_PHYS(oldl3) | (oldl3 & ATTR_DESCR_MASK)) != pa) {
5419 			counter_u64_add(pmap_l3c_p_failures, 1);
5420 			CTR2(KTR_PMAP, "pmap_promote_l3c: failure for va %#lx"
5421 			    " in pmap %p", va, pmap);
5422 			return (false);
5423 		}
5424 set_l3:
5425 		if ((oldl3 & (ATTR_S1_AP_RW_BIT | ATTR_SW_DBM)) ==
5426 		    (ATTR_S1_AP(ATTR_S1_AP_RO) | ATTR_SW_DBM)) {
5427 			/*
5428 			 * When the mapping is clean, i.e., ATTR_S1_AP_RO is
5429 			 * set, ATTR_SW_DBM can be cleared without a TLB
5430 			 * invalidation.
5431 			 */
5432 			if (!atomic_fcmpset_64(l3, &oldl3, oldl3 &
5433 			    ~ATTR_SW_DBM))
5434 				goto set_l3;
5435 			oldl3 &= ~ATTR_SW_DBM;
5436 			CTR2(KTR_PMAP, "pmap_promote_l3c: protect for va %#lx"
5437 			    " in pmap %p", (oldl3 & ~ATTR_MASK & L3C_OFFSET) |
5438 			    (va & ~L3C_OFFSET), pmap);
5439 		}
5440 		if ((oldl3 & ATTR_PROMOTE) != (firstl3c & ATTR_PROMOTE)) {
5441 			counter_u64_add(pmap_l3c_p_failures, 1);
5442 			CTR2(KTR_PMAP, "pmap_promote_l3c: failure for va %#lx"
5443 			    " in pmap %p", va, pmap);
5444 			return (false);
5445 		}
5446 		all_l3e_AF &= oldl3;
5447 		pa -= PAGE_SIZE;
5448 	}
5449 
5450 	/*
5451 	 * Unless all PTEs have ATTR_AF set, clear it from the superpage
5452 	 * mapping, so that promotions triggered by speculative mappings,
5453 	 * such as pmap_enter_quick(), don't automatically mark the
5454 	 * underlying pages as referenced.
5455 	 */
5456 	firstl3c &= ~ATTR_AF | all_l3e_AF;
5457 
5458 	/*
5459 	 * Remake the mappings with the contiguous bit set.
5460 	 */
5461 	pmap_update_strided(pmap, l3p, l3p + L3C_ENTRIES, firstl3c |
5462 	    ATTR_CONTIGUOUS, va & ~L3C_OFFSET, L3_SIZE, L3C_SIZE);
5463 
5464 	counter_u64_add(pmap_l3c_promotions, 1);
5465 	CTR2(KTR_PMAP, "pmap_promote_l3c: success for va %#lx in pmap %p", va,
5466 	    pmap);
5467 	return (true);
5468 }
5469 #endif /* VM_NRESERVLEVEL > 0 */
5470 
5471 static int
5472 pmap_enter_largepage(pmap_t pmap, vm_offset_t va, pt_entry_t pte, int flags,
5473     int psind)
5474 {
5475 	pd_entry_t *l0p, *l1p, *l2p, *l3p, newpte, origpte, *tl3p;
5476 	vm_page_t mp;
5477 
5478 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
5479 	KASSERT(psind > 0 && psind < MAXPAGESIZES,
5480 	    ("psind %d unexpected", psind));
5481 	KASSERT((PTE_TO_PHYS(pte) & (pagesizes[psind] - 1)) == 0,
5482 	    ("unaligned phys address %#lx pte %#lx psind %d",
5483 	    PTE_TO_PHYS(pte), pte, psind));
5484 
5485 restart:
5486 	newpte = pte;
5487 	if (!pmap_bti_same(pmap, va, va + pagesizes[psind], &newpte))
5488 		return (KERN_PROTECTION_FAILURE);
5489 	if (psind == 3) {
5490 		PMAP_ASSERT_L1_BLOCKS_SUPPORTED;
5491 
5492 		KASSERT(pagesizes[psind] == L1_SIZE,
5493 		    ("pagesizes[%d] != L1_SIZE", psind));
5494 		l0p = pmap_l0(pmap, va);
5495 		if ((pmap_load(l0p) & ATTR_DESCR_VALID) == 0) {
5496 			mp = _pmap_alloc_l3(pmap, pmap_l0_pindex(va), NULL);
5497 			if (mp == NULL) {
5498 				if ((flags & PMAP_ENTER_NOSLEEP) != 0)
5499 					return (KERN_RESOURCE_SHORTAGE);
5500 				PMAP_UNLOCK(pmap);
5501 				vm_wait(NULL);
5502 				PMAP_LOCK(pmap);
5503 				goto restart;
5504 			}
5505 			l1p = pmap_l0_to_l1(l0p, va);
5506 			KASSERT(l1p != NULL, ("va %#lx lost l1 entry", va));
5507 			origpte = pmap_load(l1p);
5508 		} else {
5509 			l1p = pmap_l0_to_l1(l0p, va);
5510 			KASSERT(l1p != NULL, ("va %#lx lost l1 entry", va));
5511 			origpte = pmap_load(l1p);
5512 			if ((origpte & ATTR_DESCR_VALID) == 0) {
5513 				mp = PTE_TO_VM_PAGE(pmap_load(l0p));
5514 				mp->ref_count++;
5515 			}
5516 		}
5517 		KASSERT((PTE_TO_PHYS(origpte) == PTE_TO_PHYS(newpte) &&
5518 		    (origpte & ATTR_DESCR_MASK) == L1_BLOCK) ||
5519 		    (origpte & ATTR_DESCR_VALID) == 0,
5520 		    ("va %#lx changing 1G phys page l1 %#lx newpte %#lx",
5521 		    va, origpte, newpte));
5522 		pmap_store(l1p, newpte);
5523 	} else if (psind == 2) {
5524 		KASSERT(pagesizes[psind] == L2_SIZE,
5525 		    ("pagesizes[%d] != L2_SIZE", psind));
5526 		l2p = pmap_l2(pmap, va);
5527 		if (l2p == NULL) {
5528 			mp = _pmap_alloc_l3(pmap, pmap_l1_pindex(va), NULL);
5529 			if (mp == NULL) {
5530 				if ((flags & PMAP_ENTER_NOSLEEP) != 0)
5531 					return (KERN_RESOURCE_SHORTAGE);
5532 				PMAP_UNLOCK(pmap);
5533 				vm_wait(NULL);
5534 				PMAP_LOCK(pmap);
5535 				goto restart;
5536 			}
5537 			l2p = VM_PAGE_TO_DMAP(mp);
5538 			l2p = &l2p[pmap_l2_index(va)];
5539 			origpte = pmap_load(l2p);
5540 		} else {
5541 			l1p = pmap_l1(pmap, va);
5542 			origpte = pmap_load(l2p);
5543 			if ((origpte & ATTR_DESCR_VALID) == 0) {
5544 				mp = PTE_TO_VM_PAGE(pmap_load(l1p));
5545 				mp->ref_count++;
5546 			}
5547 		}
5548 		KASSERT((origpte & ATTR_DESCR_VALID) == 0 ||
5549 		    ((origpte & ATTR_DESCR_MASK) == L2_BLOCK &&
5550 		    PTE_TO_PHYS(origpte) == PTE_TO_PHYS(newpte)),
5551 		    ("va %#lx changing 2M phys page l2 %#lx newpte %#lx",
5552 		    va, origpte, newpte));
5553 		pmap_store(l2p, newpte);
5554 	} else /* (psind == 1) */ {
5555 		KASSERT(pagesizes[psind] == L3C_SIZE,
5556 		    ("pagesizes[%d] != L3C_SIZE", psind));
5557 		l2p = pmap_l2(pmap, va);
5558 		if (l2p == NULL || (pmap_load(l2p) & ATTR_DESCR_VALID) == 0) {
5559 			mp = _pmap_alloc_l3(pmap, pmap_l2_pindex(va), NULL);
5560 			if (mp == NULL) {
5561 				if ((flags & PMAP_ENTER_NOSLEEP) != 0)
5562 					return (KERN_RESOURCE_SHORTAGE);
5563 				PMAP_UNLOCK(pmap);
5564 				vm_wait(NULL);
5565 				PMAP_LOCK(pmap);
5566 				goto restart;
5567 			}
5568 			mp->ref_count += L3C_ENTRIES - 1;
5569 			l3p = VM_PAGE_TO_DMAP(mp);
5570 			l3p = &l3p[pmap_l3_index(va)];
5571 		} else {
5572 			l3p = pmap_l2_to_l3(l2p, va);
5573 			if ((pmap_load(l3p) & ATTR_DESCR_VALID) == 0) {
5574 				mp = PTE_TO_VM_PAGE(pmap_load(l2p));
5575 				mp->ref_count += L3C_ENTRIES;
5576 			}
5577 		}
5578 		for (tl3p = l3p; tl3p < &l3p[L3C_ENTRIES]; tl3p++) {
5579 			origpte = pmap_load(tl3p);
5580 			KASSERT((origpte & ATTR_DESCR_VALID) == 0 ||
5581 			    ((origpte & ATTR_CONTIGUOUS) != 0 &&
5582 			    PTE_TO_PHYS(origpte) == PTE_TO_PHYS(newpte)),
5583 			    ("va %#lx changing 64K phys page l3 %#lx newpte %#lx",
5584 			    va, origpte, newpte));
5585 			pmap_store(tl3p, newpte);
5586 			newpte += L3_SIZE;
5587 		}
5588 	}
5589 	dsb(ishst);
5590 
5591 	if ((origpte & ATTR_DESCR_VALID) == 0)
5592 		pmap_resident_count_inc(pmap, pagesizes[psind] / PAGE_SIZE);
5593 	if ((newpte & ATTR_SW_WIRED) != 0 && (origpte & ATTR_SW_WIRED) == 0)
5594 		pmap->pm_stats.wired_count += pagesizes[psind] / PAGE_SIZE;
5595 	else if ((newpte & ATTR_SW_WIRED) == 0 &&
5596 	    (origpte & ATTR_SW_WIRED) != 0)
5597 		pmap->pm_stats.wired_count -= pagesizes[psind] / PAGE_SIZE;
5598 
5599 	return (KERN_SUCCESS);
5600 }
5601 
5602 static void
5603 pmap_set_unprotected(pt_entry_t new_l3)
5604 {
5605 	vm_paddr_t pa;
5606 
5607 	pa = PTE_TO_PHYS(new_l3) & ~prot_ns_shared_pa;
5608 
5609 	rsi_set_addr_range_state(pa, pa + L3_SIZE, RSI_RIPAS_EMPTY,
5610 	    RSI_CHANGE_DESTROYED, NULL);
5611 }
5612 
5613 static void
5614 pmap_set_protected(pt_entry_t old_l3)
5615 {
5616 	vm_paddr_t pa;
5617 
5618 	pa = PTE_TO_PHYS(old_l3) & ~prot_ns_shared_pa;
5619 
5620 	rsi_set_addr_range_state(pa, pa + L3_SIZE, RSI_RIPAS_RAM,
5621 	    RSI_CHANGE_DESTROYED, NULL);
5622 }
5623 
5624 /*
5625  *	Insert the given physical page (p) at
5626  *	the specified virtual address (v) in the
5627  *	target physical map with the protection requested.
5628  *
5629  *	If specified, the page will be wired down, meaning
5630  *	that the related pte can not be reclaimed.
5631  *
5632  *	NB:  This is the only routine which MAY NOT lazy-evaluate
5633  *	or lose information.  That is, this routine must actually
5634  *	insert this page into the given map NOW.
5635  */
5636 int
5637 pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot,
5638     u_int flags, int8_t psind)
5639 {
5640 	struct rwlock *lock;
5641 	pd_entry_t *pde;
5642 	pt_entry_t new_l3, orig_l3;
5643 	pt_entry_t *l2, *l3;
5644 	pv_entry_t pv;
5645 	vm_paddr_t opa, pa;
5646 	vm_page_t mpte, om;
5647 	bool nosleep;
5648 	int full_lvl, lvl, rv;
5649 
5650 	KASSERT(ADDR_IS_CANONICAL(va),
5651 	    ("%s: Address not in canonical form: %lx", __func__, va));
5652 
5653 	va = trunc_page(va);
5654 	if ((m->oflags & VPO_UNMANAGED) == 0)
5655 		VM_PAGE_OBJECT_BUSY_ASSERT(m);
5656 	pa = VM_PAGE_TO_PHYS(m);
5657 	if (in_realm() && (flags & PMAP_ENTER_UNPROTECTED) != 0)
5658 		pa |= prot_ns_shared_pa;
5659 	new_l3 = (pt_entry_t)(PHYS_TO_PTE(pa) | ATTR_AF | pmap_sh_attr |
5660 	    L3_PAGE);
5661 	new_l3 |= pmap_pte_memattr(pmap, m->md.pv_memattr);
5662 	new_l3 |= pmap_pte_prot(pmap, prot);
5663 	if ((flags & PMAP_ENTER_WIRED) != 0)
5664 		new_l3 |= ATTR_SW_WIRED;
5665 	if (pmap->pm_stage == PM_STAGE1) {
5666 		if (ADDR_IS_USER(va))
5667 			new_l3 |= ATTR_S1_AP(ATTR_S1_AP_USER) | ATTR_S1_PXN;
5668 		else
5669 			new_l3 |= ATTR_S1_UXN;
5670 		if (pmap != kernel_pmap)
5671 			new_l3 |= ATTR_S1_nG;
5672 	} else {
5673 		/*
5674 		 * Clear the access flag on executable mappings, this will be
5675 		 * set later when the page is accessed. The fault handler is
5676 		 * required to invalidate the I-cache.
5677 		 *
5678 		 * TODO: Switch to the valid flag to allow hardware management
5679 		 * of the access flag. Much of the pmap code assumes the
5680 		 * valid flag is set and fails to destroy the old page tables
5681 		 * correctly if it is clear.
5682 		 */
5683 		if (prot & VM_PROT_EXECUTE)
5684 			new_l3 &= ~ATTR_AF;
5685 	}
5686 	if ((m->oflags & VPO_UNMANAGED) == 0) {
5687 		new_l3 |= ATTR_SW_MANAGED;
5688 		if ((prot & VM_PROT_WRITE) != 0) {
5689 			new_l3 |= ATTR_SW_DBM;
5690 			if ((flags & VM_PROT_WRITE) == 0) {
5691 				if (pmap->pm_stage == PM_STAGE1)
5692 					new_l3 |= ATTR_S1_AP(ATTR_S1_AP_RO);
5693 				else
5694 					new_l3 &=
5695 					    ~ATTR_S2_S2AP(ATTR_S2_S2AP_WRITE);
5696 			}
5697 		}
5698 	}
5699 
5700 	CTR2(KTR_PMAP, "pmap_enter: %.16lx -> %.16lx", va, pa);
5701 
5702 	lock = NULL;
5703 	PMAP_LOCK(pmap);
5704 	if ((flags & PMAP_ENTER_LARGEPAGE) != 0) {
5705 		KASSERT((m->oflags & VPO_UNMANAGED) != 0,
5706 		    ("managed largepage va %#lx flags %#x", va, flags));
5707 		if (psind == 3) {
5708 			PMAP_ASSERT_L1_BLOCKS_SUPPORTED;
5709 			new_l3 &= ~L3_PAGE;
5710 			new_l3 |= L1_BLOCK;
5711 		} else if (psind == 2) {
5712 			new_l3 &= ~L3_PAGE;
5713 			new_l3 |= L2_BLOCK;
5714 		} else /* (psind == 1) */
5715 			new_l3 |= ATTR_CONTIGUOUS;
5716 		rv = pmap_enter_largepage(pmap, va, new_l3, flags, psind);
5717 		goto out;
5718 	}
5719 	if (psind == 2) {
5720 		/* Assert the required virtual and physical alignment. */
5721 		KASSERT((va & L2_OFFSET) == 0, ("pmap_enter: va unaligned"));
5722 		KASSERT(m->psind > 1, ("pmap_enter: m->psind < psind"));
5723 		rv = pmap_enter_l2(pmap, va, (new_l3 & ~L3_PAGE) | L2_BLOCK,
5724 		    flags, m, &lock);
5725 		goto out;
5726 	}
5727 	mpte = NULL;
5728 	if (psind == 1) {
5729 		KASSERT((va & L3C_OFFSET) == 0, ("pmap_enter: va unaligned"));
5730 		KASSERT(m->psind > 0, ("pmap_enter: m->psind < psind"));
5731 		rv = pmap_enter_l3c(pmap, va, new_l3 | ATTR_CONTIGUOUS, flags,
5732 		    m, &mpte, &lock);
5733 #if VM_NRESERVLEVEL > 0
5734 		/*
5735 		 * Attempt L2 promotion, if both the PTP and a level 1
5736 		 * reservation are fully populated.
5737 		 */
5738 		if (rv == KERN_SUCCESS &&
5739 		    (mpte == NULL || mpte->ref_count == NL3PG) &&
5740 		    (m->flags & PG_FICTITIOUS) == 0 &&
5741 		    vm_reserv_level_iffullpop(m) == 1) {
5742 			pde = pmap_l2(pmap, va);
5743 			(void)pmap_promote_l2(pmap, pde, va, mpte, &lock);
5744 		}
5745 #endif
5746 		goto out;
5747 	}
5748 
5749 	/*
5750 	 * In the case that a page table page is not
5751 	 * resident, we are creating it here.
5752 	 */
5753 retry:
5754 	pde = pmap_pde(pmap, va, &lvl);
5755 	if (pde != NULL && lvl == 2) {
5756 		l3 = pmap_l2_to_l3(pde, va);
5757 		if (ADDR_IS_USER(va) && mpte == NULL) {
5758 			mpte = PTE_TO_VM_PAGE(pmap_load(pde));
5759 			mpte->ref_count++;
5760 		}
5761 		goto havel3;
5762 	} else if (pde != NULL && lvl == 1) {
5763 		l2 = pmap_l1_to_l2(pde, va);
5764 		if ((pmap_load(l2) & ATTR_DESCR_MASK) == L2_BLOCK &&
5765 		    (l3 = pmap_demote_l2_locked(pmap, l2, va, &lock)) != NULL) {
5766 			l3 = &l3[pmap_l3_index(va)];
5767 			if (ADDR_IS_USER(va)) {
5768 				mpte = PTE_TO_VM_PAGE(pmap_load(l2));
5769 				mpte->ref_count++;
5770 			}
5771 			goto havel3;
5772 		}
5773 		/* We need to allocate an L3 table. */
5774 	}
5775 	if (ADDR_IS_USER(va)) {
5776 		nosleep = (flags & PMAP_ENTER_NOSLEEP) != 0;
5777 
5778 		/*
5779 		 * We use _pmap_alloc_l3() instead of pmap_alloc_l3() in order
5780 		 * to handle the possibility that a superpage mapping for "va"
5781 		 * was created while we slept.
5782 		 */
5783 		mpte = _pmap_alloc_l3(pmap, pmap_l2_pindex(va),
5784 		    nosleep ? NULL : &lock);
5785 		if (mpte == NULL && nosleep) {
5786 			CTR0(KTR_PMAP, "pmap_enter: mpte == NULL");
5787 			rv = KERN_RESOURCE_SHORTAGE;
5788 			goto out;
5789 		}
5790 		goto retry;
5791 	} else
5792 		panic("pmap_enter: missing L3 table for kernel va %#lx", va);
5793 
5794 havel3:
5795 	orig_l3 = pmap_load(l3);
5796 	opa = PTE_TO_PHYS(orig_l3);
5797 	pv = NULL;
5798 	new_l3 |= pmap_pte_bti(pmap, va);
5799 
5800 	/*
5801 	 * Is the specified virtual address already mapped?
5802 	 */
5803 	if (pmap_l3_valid(orig_l3)) {
5804 		/*
5805 		 * Wiring change, just update stats. We don't worry about
5806 		 * wiring PT pages as they remain resident as long as there
5807 		 * are valid mappings in them. Hence, if a user page is wired,
5808 		 * the PT page will be also.
5809 		 */
5810 		if ((flags & PMAP_ENTER_WIRED) != 0 &&
5811 		    (orig_l3 & ATTR_SW_WIRED) == 0)
5812 			pmap->pm_stats.wired_count++;
5813 		else if ((flags & PMAP_ENTER_WIRED) == 0 &&
5814 		    (orig_l3 & ATTR_SW_WIRED) != 0)
5815 			pmap->pm_stats.wired_count--;
5816 
5817 		/*
5818 		 * Remove the extra PT page reference.
5819 		 */
5820 		if (mpte != NULL) {
5821 			mpte->ref_count--;
5822 			KASSERT(mpte->ref_count > 0,
5823 			    ("pmap_enter: missing reference to page table page,"
5824 			     " va: 0x%lx", va));
5825 		}
5826 
5827 		/*
5828 		 * Has the physical page changed?
5829 		 */
5830 		if (opa == pa) {
5831 			/*
5832 			 * No, might be a protection or wiring change.
5833 			 */
5834 			if ((orig_l3 & ATTR_SW_MANAGED) != 0 &&
5835 			    (new_l3 & ATTR_SW_DBM) != 0)
5836 				vm_page_aflag_set(m, PGA_WRITEABLE);
5837 			goto validate;
5838 		}
5839 
5840 		/*
5841 		 * The physical page has changed.  Temporarily invalidate
5842 		 * the mapping.
5843 		 */
5844 		if ((orig_l3 & ATTR_CONTIGUOUS) != 0)
5845 			(void)pmap_demote_l3c(pmap, l3, va);
5846 		orig_l3 = pmap_load_clear(l3);
5847 		KASSERT(PTE_TO_PHYS(orig_l3) == opa,
5848 		    ("pmap_enter: unexpected pa update for %#lx", va));
5849 		if ((orig_l3 & ATTR_SW_MANAGED) != 0) {
5850 			om = PHYS_TO_VM_PAGE(opa);
5851 
5852 			/*
5853 			 * The pmap lock is sufficient to synchronize with
5854 			 * concurrent calls to pmap_page_test_mappings() and
5855 			 * pmap_ts_referenced().
5856 			 */
5857 			if (pmap_pte_dirty(pmap, orig_l3))
5858 				vm_page_dirty(om);
5859 			if ((orig_l3 & ATTR_AF) != 0) {
5860 				pmap_invalidate_page(pmap, va, true);
5861 				vm_page_aflag_set(om, PGA_REFERENCED);
5862 			}
5863 			CHANGE_PV_LIST_LOCK_TO_VM_PAGE(&lock, om);
5864 			pv = pmap_pvh_remove(&om->md, pmap, va);
5865 			if ((m->oflags & VPO_UNMANAGED) != 0)
5866 				free_pv_entry(pmap, pv);
5867 
5868 			/*
5869 			 * The old page is likely COW, so check "writeable"
5870 			 * first.
5871 			 */
5872 			if ((om->a.flags & PGA_WRITEABLE) != 0 &&
5873 			    !pmap_page_is_mapped_locked(om))
5874 				vm_page_aflag_clear(om, PGA_WRITEABLE);
5875 		} else {
5876 			KASSERT((orig_l3 & ATTR_AF) != 0,
5877 			    ("pmap_enter: unmanaged mapping lacks ATTR_AF"));
5878 			pmap_invalidate_page(pmap, va, true);
5879 		}
5880 		orig_l3 = 0;
5881 	} else {
5882 		/*
5883 		 * Increment the counters.
5884 		 */
5885 		if ((new_l3 & ATTR_SW_WIRED) != 0)
5886 			pmap->pm_stats.wired_count++;
5887 		pmap_resident_count_inc(pmap, 1);
5888 	}
5889 	/*
5890 	 * Enter on the PV list if part of our managed memory.
5891 	 */
5892 	if ((m->oflags & VPO_UNMANAGED) == 0) {
5893 		if (pv == NULL) {
5894 			pv = get_pv_entry(pmap, &lock);
5895 			pv->pv_va = va;
5896 		}
5897 		CHANGE_PV_LIST_LOCK_TO_VM_PAGE(&lock, m);
5898 		TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_next);
5899 		m->md.pv_gen++;
5900 		if ((new_l3 & ATTR_SW_DBM) != 0)
5901 			vm_page_aflag_set(m, PGA_WRITEABLE);
5902 	}
5903 
5904 validate:
5905 	if (pmap->pm_stage == PM_STAGE1) {
5906 		/*
5907 		 * Sync icache if exec permission and attribute
5908 		 * VM_MEMATTR_WRITE_BACK is set. Do it now, before the mapping
5909 		 * is stored and made valid for hardware table walk. If done
5910 		 * later, then other can access this page before caches are
5911 		 * properly synced. Don't do it for kernel memory which is
5912 		 * mapped with exec permission even if the memory isn't going
5913 		 * to hold executable code. The only time when icache sync is
5914 		 * needed is after kernel module is loaded and the relocation
5915 		 * info is processed. And it's done in elf_cpu_load_file().
5916 		*/
5917 		if ((prot & VM_PROT_EXECUTE) &&  pmap != kernel_pmap &&
5918 		    m->md.pv_memattr == VM_MEMATTR_WRITE_BACK &&
5919 		    (opa != pa || (orig_l3 & ATTR_S1_UXN) != 0)) {
5920 			PMAP_ASSERT_STAGE1(pmap);
5921 			cpu_icache_sync_range(PHYS_TO_DMAP(pa), PAGE_SIZE);
5922 		}
5923 	} else {
5924 		cpu_dcache_wb_range(PHYS_TO_DMAP(pa), PAGE_SIZE);
5925 	}
5926 
5927 	/*
5928 	 * Update the L3 entry
5929 	 */
5930 	if (pmap_l3_valid(orig_l3)) {
5931 		KASSERT(opa == pa, ("pmap_enter: invalid update"));
5932 		if ((orig_l3 & ~ATTR_AF) != (new_l3 & ~ATTR_AF)) {
5933 			/* same PA, different attributes */
5934 			if ((orig_l3 & ATTR_CONTIGUOUS) != 0)
5935 				(void)pmap_demote_l3c(pmap, l3, va);
5936 			orig_l3 = pmap_load_store(l3, new_l3);
5937 			pmap_invalidate_page(pmap, va, true);
5938 			if ((orig_l3 & ATTR_SW_MANAGED) != 0 &&
5939 			    pmap_pte_dirty(pmap, orig_l3))
5940 				vm_page_dirty(m);
5941 		} else {
5942 			/*
5943 			 * orig_l3 == new_l3
5944 			 * This can happens if multiple threads simultaneously
5945 			 * access not yet mapped page. This bad for performance
5946 			 * since this can cause full demotion-NOP-promotion
5947 			 * cycle.
5948 			 * Another possible reasons are:
5949 			 * - VM and pmap memory layout are diverged
5950 			 * - tlb flush is missing somewhere and CPU doesn't see
5951 			 *   actual mapping.
5952 			 */
5953 			CTR4(KTR_PMAP, "%s: already mapped page - "
5954 			    "pmap %p va 0x%#lx pte 0x%lx",
5955 			    __func__, pmap, va, new_l3);
5956 		}
5957 	} else {
5958 		/* New mapping */
5959 		pmap_store(l3, new_l3);
5960 		dsb(ishst);
5961 	}
5962 
5963 #if VM_NRESERVLEVEL > 0
5964 	/*
5965 	 * First, attempt L3C promotion, if the virtual and physical addresses
5966 	 * are aligned with each other and an underlying reservation has the
5967 	 * neighboring L3 pages allocated.  The first condition is simply an
5968 	 * optimization that recognizes some eventual promotion failures early
5969 	 * at a lower run-time cost.  Then, if both a level 1 reservation and
5970 	 * the PTP are fully populated, attempt L2 promotion.
5971 	 */
5972 	if ((va & L3C_OFFSET) == (pa & L3C_OFFSET) &&
5973 	    (m->flags & PG_FICTITIOUS) == 0 &&
5974 	    (full_lvl = vm_reserv_level_iffullpop(m)) >= 0 &&
5975 	    pmap_promote_l3c(pmap, l3, va) &&
5976 	    full_lvl == 1 && (mpte == NULL || mpte->ref_count == NL3PG))
5977 		(void)pmap_promote_l2(pmap, pde, va, mpte, &lock);
5978 #endif
5979 
5980 	rv = KERN_SUCCESS;
5981 
5982 	if (in_realm() && (flags & PMAP_ENTER_UNPROTECTED) != 0)
5983 		pmap_set_unprotected(new_l3);
5984 
5985 out:
5986 	if (lock != NULL)
5987 		rw_wunlock(lock);
5988 	PMAP_UNLOCK(pmap);
5989 	return (rv);
5990 }
5991 
5992 /*
5993  * Tries to create a read- and/or execute-only L2 page mapping.  Returns
5994  * KERN_SUCCESS if the mapping was created.  Otherwise, returns an error
5995  * value.  See pmap_enter_l2() for the possible error values when "no sleep",
5996  * "no replace", and "no reclaim" are specified.
5997  */
5998 static int
5999 pmap_enter_l2_rx(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot,
6000     struct rwlock **lockp)
6001 {
6002 	pd_entry_t new_l2;
6003 
6004 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
6005 	PMAP_ASSERT_STAGE1(pmap);
6006 	KASSERT(ADDR_IS_CANONICAL(va),
6007 	    ("%s: Address not in canonical form: %lx", __func__, va));
6008 
6009 	new_l2 = (pd_entry_t)(VM_PAGE_TO_PTE(m) | pmap_sh_attr |
6010 	    ATTR_S1_IDX(m->md.pv_memattr) | ATTR_S1_AP(ATTR_S1_AP_RO) |
6011 	    L2_BLOCK);
6012 	if ((m->oflags & VPO_UNMANAGED) == 0)
6013 		new_l2 |= ATTR_SW_MANAGED;
6014 	else
6015 		new_l2 |= ATTR_AF;
6016 	if ((prot & VM_PROT_EXECUTE) == 0 ||
6017 	    m->md.pv_memattr == VM_MEMATTR_DEVICE)
6018 		new_l2 |= ATTR_S1_XN;
6019 	if (ADDR_IS_USER(va))
6020 		new_l2 |= ATTR_S1_AP(ATTR_S1_AP_USER) | ATTR_S1_PXN;
6021 	else
6022 		new_l2 |= ATTR_S1_UXN;
6023 	if (pmap != kernel_pmap)
6024 		new_l2 |= ATTR_S1_nG;
6025 	return (pmap_enter_l2(pmap, va, new_l2, PMAP_ENTER_NOSLEEP |
6026 	    PMAP_ENTER_NOREPLACE | PMAP_ENTER_NORECLAIM, m, lockp));
6027 }
6028 
6029 /*
6030  * Returns true if every page table entry in the specified page table is
6031  * zero.
6032  */
6033 static bool
6034 pmap_every_pte_zero(vm_paddr_t pa)
6035 {
6036 	pt_entry_t *pt_end, *pte;
6037 
6038 	KASSERT((pa & PAGE_MASK) == 0, ("pa is misaligned"));
6039 	pte = PHYS_TO_DMAP(pa);
6040 	for (pt_end = pte + Ln_ENTRIES; pte < pt_end; pte++) {
6041 		if (*pte != 0)
6042 			return (false);
6043 	}
6044 	return (true);
6045 }
6046 
6047 /*
6048  * Tries to create the specified L2 page mapping.  Returns KERN_SUCCESS if
6049  * the mapping was created, and one of KERN_FAILURE, KERN_NO_SPACE, or
6050  * KERN_RESOURCE_SHORTAGE otherwise.  Returns KERN_FAILURE if
6051  * PMAP_ENTER_NOREPLACE was specified and a base page mapping already exists
6052  * within the L2 virtual address range starting at the specified virtual
6053  * address.  Returns KERN_NO_SPACE if PMAP_ENTER_NOREPLACE was specified and a
6054  * L2 page mapping already exists at the specified virtual address.  Returns
6055  * KERN_RESOURCE_SHORTAGE if either (1) PMAP_ENTER_NOSLEEP was specified and a
6056  * page table page allocation failed or (2) PMAP_ENTER_NORECLAIM was specified
6057  * and a PV entry allocation failed.
6058  */
6059 static int
6060 pmap_enter_l2(pmap_t pmap, vm_offset_t va, pd_entry_t new_l2, u_int flags,
6061     vm_page_t m, struct rwlock **lockp)
6062 {
6063 	struct spglist free;
6064 	pd_entry_t *l2, old_l2;
6065 	vm_page_t l2pg, mt;
6066 	vm_page_t uwptpg;
6067 
6068 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
6069 	KASSERT(ADDR_IS_CANONICAL(va),
6070 	    ("%s: Address not in canonical form: %lx", __func__, va));
6071 	KASSERT((flags & (PMAP_ENTER_NOREPLACE | PMAP_ENTER_NORECLAIM)) !=
6072 	    PMAP_ENTER_NORECLAIM,
6073 	    ("pmap_enter_l2: flags is missing PMAP_ENTER_NOREPLACE"));
6074 
6075 	if ((l2 = pmap_alloc_l2(pmap, va, &l2pg, (flags &
6076 	    PMAP_ENTER_NOSLEEP) != 0 ? NULL : lockp)) == NULL) {
6077 		CTR2(KTR_PMAP, "pmap_enter_l2: failure for va %#lx in pmap %p",
6078 		    va, pmap);
6079 		return (KERN_RESOURCE_SHORTAGE);
6080 	}
6081 
6082 	/*
6083 	 * If bti is not the same for the whole l2 range, return failure
6084 	 * and let vm_fault() cope.  Check after l2 allocation, since
6085 	 * it could sleep.
6086 	 */
6087 	if (!pmap_bti_same(pmap, va, va + L2_SIZE, &new_l2)) {
6088 		KASSERT(l2pg != NULL, ("pmap_enter_l2: missing L2 PTP"));
6089 		pmap_abort_ptp(pmap, va, l2pg);
6090 		return (KERN_PROTECTION_FAILURE);
6091 	}
6092 
6093 	/*
6094 	 * If there are existing mappings, either abort or remove them.
6095 	 */
6096 	if ((old_l2 = pmap_load(l2)) != 0) {
6097 		KASSERT(l2pg == NULL || l2pg->ref_count > 1,
6098 		    ("pmap_enter_l2: l2pg's ref count is too low"));
6099 		if ((flags & PMAP_ENTER_NOREPLACE) != 0) {
6100 			if ((old_l2 & ATTR_DESCR_MASK) == L2_BLOCK) {
6101 				if (l2pg != NULL)
6102 					l2pg->ref_count--;
6103 				CTR2(KTR_PMAP,
6104 				    "pmap_enter_l2: no space for va %#lx"
6105 				    " in pmap %p", va, pmap);
6106 				return (KERN_NO_SPACE);
6107 			} else if (ADDR_IS_USER(va) ||
6108 			    !pmap_every_pte_zero(PTE_TO_PHYS(old_l2))) {
6109 				if (l2pg != NULL)
6110 					l2pg->ref_count--;
6111 				CTR2(KTR_PMAP,
6112 				    "pmap_enter_l2: failure for va %#lx"
6113 				    " in pmap %p", va, pmap);
6114 				return (KERN_FAILURE);
6115 			}
6116 		}
6117 		SLIST_INIT(&free);
6118 		if ((old_l2 & ATTR_DESCR_MASK) == L2_BLOCK) {
6119 			(void)pmap_remove_l2(pmap, l2, va,
6120 			    pmap_load(pmap_l1(pmap, va)), false, &free, lockp);
6121 		} else {
6122 			if (ADDR_IS_KERNEL(va)) {
6123 				/*
6124 				 * Try to save the ptp in the trie
6125 				 * before any changes to mappings are
6126 				 * made.  Abort on failure.
6127 				 */
6128 				mt = PTE_TO_VM_PAGE(old_l2);
6129 				if (pmap_insert_pt_page(pmap, mt, false,
6130 				    false)) {
6131 					CTR1(KTR_PMAP,
6132 			    "pmap_enter_l2: cannot ins kern ptp va %#lx",
6133 					    va);
6134 					return (KERN_RESOURCE_SHORTAGE);
6135 				}
6136 				/*
6137 				 * Both pmap_remove_l2() and
6138 				 * pmap_remove_l3_range() will zero fill
6139 				 * the L3 kernel page table page.
6140 				 */
6141 			}
6142 			pmap_remove_l3_range(pmap, old_l2, va, va + L2_SIZE,
6143 			    &free, lockp);
6144 			if (ADDR_IS_KERNEL(va)) {
6145 				/*
6146 				 * The TLB could have an intermediate
6147 				 * entry for the L3 kernel page table
6148 				 * page, so request an invalidation at
6149 				 * all levels after clearing the
6150 				 * L2_TABLE entry.
6151 				 */
6152 				pmap_clear(l2);
6153 				pmap_s1_invalidate_page(pmap, va, false);
6154 			}
6155 		}
6156 		KASSERT(pmap_load(l2) == 0,
6157 		    ("pmap_enter_l2: non-zero L2 entry %p", l2));
6158 		if (ADDR_IS_USER(va)) {
6159 			vm_page_free_pages_toq(&free, true);
6160 		} else {
6161 			KASSERT(SLIST_EMPTY(&free),
6162 			    ("pmap_enter_l2: freed kernel page table page"));
6163 		}
6164 	}
6165 
6166 	/*
6167 	 * Allocate leaf ptpage for wired userspace pages.
6168 	 */
6169 	uwptpg = NULL;
6170 	if ((new_l2 & ATTR_SW_WIRED) != 0 && pmap != kernel_pmap) {
6171 		uwptpg = vm_page_alloc_noobj(VM_ALLOC_WIRED);
6172 		if (uwptpg == NULL) {
6173 			pmap_abort_ptp(pmap, va, l2pg);
6174 			return (KERN_RESOURCE_SHORTAGE);
6175 		}
6176 		uwptpg->pindex = pmap_l2_pindex(va);
6177 		if (pmap_insert_pt_page(pmap, uwptpg, true, false)) {
6178 			vm_page_unwire_noq(uwptpg);
6179 			vm_page_free(uwptpg);
6180 			pmap_abort_ptp(pmap, va, l2pg);
6181 			return (KERN_RESOURCE_SHORTAGE);
6182 		}
6183 		pmap_resident_count_inc(pmap, 1);
6184 		uwptpg->ref_count = NL3PG;
6185 	}
6186 	if ((new_l2 & ATTR_SW_MANAGED) != 0) {
6187 		/*
6188 		 * Abort this mapping if its PV entry could not be created.
6189 		 */
6190 		if (!pmap_pv_insert_l2(pmap, va, new_l2, flags, lockp)) {
6191 			if (l2pg != NULL)
6192 				pmap_abort_ptp(pmap, va, l2pg);
6193 			else {
6194 				KASSERT(ADDR_IS_KERNEL(va) &&
6195 				    (pmap_load(l2) & ATTR_DESCR_MASK) ==
6196 				    L2_TABLE,
6197 				    ("pmap_enter_l2: invalid kernel L2E"));
6198 				mt = pmap_remove_pt_page(pmap, va);
6199 				KASSERT(mt != NULL,
6200 				    ("pmap_enter_l2: missing kernel PTP"));
6201 			}
6202 			if (uwptpg != NULL) {
6203 				mt = pmap_remove_pt_page(pmap, va);
6204 				KASSERT(mt == uwptpg,
6205 				    ("removed pt page %p, expected %p", mt,
6206 				    uwptpg));
6207 				pmap_resident_count_dec(pmap, 1);
6208 				uwptpg->ref_count = 1;
6209 				vm_page_unwire_noq(uwptpg);
6210 				vm_page_free(uwptpg);
6211 			}
6212 			CTR2(KTR_PMAP,
6213 			    "pmap_enter_l2: failure for va %#lx in pmap %p",
6214 			    va, pmap);
6215 			return (KERN_RESOURCE_SHORTAGE);
6216 		}
6217 		if ((new_l2 & ATTR_SW_DBM) != 0)
6218 			for (mt = m; mt < &m[L2_SIZE / PAGE_SIZE]; mt++)
6219 				vm_page_aflag_set(mt, PGA_WRITEABLE);
6220 	}
6221 
6222 	/*
6223 	 * Increment counters.
6224 	 */
6225 	if ((new_l2 & ATTR_SW_WIRED) != 0)
6226 		pmap->pm_stats.wired_count += L2_SIZE / PAGE_SIZE;
6227 	pmap->pm_stats.resident_count += L2_SIZE / PAGE_SIZE;
6228 
6229 	/*
6230 	 * Conditionally sync the icache.  See pmap_enter() for details.
6231 	 */
6232 	if ((new_l2 & ATTR_S1_UXN) == 0 && (PTE_TO_PHYS(new_l2) !=
6233 	    PTE_TO_PHYS(old_l2) || (old_l2 & ATTR_S1_UXN) != 0) &&
6234 	    pmap != kernel_pmap && m->md.pv_memattr == VM_MEMATTR_WRITE_BACK) {
6235 		cpu_icache_sync_range(PHYS_TO_DMAP(PTE_TO_PHYS(new_l2)),
6236 		    L2_SIZE);
6237 	}
6238 
6239 	/*
6240 	 * Map the superpage.
6241 	 */
6242 	pmap_store(l2, new_l2);
6243 	dsb(ishst);
6244 
6245 	counter_u64_add(pmap_l2_mappings, 1);
6246 	CTR2(KTR_PMAP, "pmap_enter_l2: success for va %#lx in pmap %p",
6247 	    va, pmap);
6248 
6249 	return (KERN_SUCCESS);
6250 }
6251 
6252 /*
6253  * Tries to create a read- and/or execute-only L3C page mapping.  Returns
6254  * KERN_SUCCESS if the mapping was created.  Otherwise, returns an error
6255  * value.
6256  */
6257 static int
6258 pmap_enter_l3c_rx(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_page_t *ml3p,
6259     vm_prot_t prot, struct rwlock **lockp)
6260 {
6261 	pt_entry_t l3e;
6262 
6263 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
6264 	PMAP_ASSERT_STAGE1(pmap);
6265 	KASSERT(ADDR_IS_CANONICAL(va),
6266 	    ("%s: Address not in canonical form: %lx", __func__, va));
6267 
6268 	l3e = VM_PAGE_TO_PTE(m) | pmap_sh_attr |
6269 	    ATTR_S1_IDX(m->md.pv_memattr) | ATTR_S1_AP(ATTR_S1_AP_RO) |
6270 	    ATTR_CONTIGUOUS | L3_PAGE;
6271 	if ((m->oflags & VPO_UNMANAGED) == 0)
6272 		l3e |= ATTR_SW_MANAGED;
6273 	else
6274 		l3e |= ATTR_AF;
6275 	if ((prot & VM_PROT_EXECUTE) == 0 ||
6276 	    m->md.pv_memattr == VM_MEMATTR_DEVICE)
6277 		l3e |= ATTR_S1_XN;
6278 	if (ADDR_IS_USER(va))
6279 		l3e |= ATTR_S1_AP(ATTR_S1_AP_USER) | ATTR_S1_PXN;
6280 	else
6281 		l3e |= ATTR_S1_UXN;
6282 	if (pmap != kernel_pmap)
6283 		l3e |= ATTR_S1_nG;
6284 	return (pmap_enter_l3c(pmap, va, l3e, PMAP_ENTER_NOSLEEP |
6285 	    PMAP_ENTER_NOREPLACE | PMAP_ENTER_NORECLAIM, m, ml3p, lockp));
6286 }
6287 
6288 static int
6289 pmap_enter_l3c(pmap_t pmap, vm_offset_t va, pt_entry_t l3e, u_int flags,
6290     vm_page_t m, vm_page_t *ml3p, struct rwlock **lockp)
6291 {
6292 	pd_entry_t *l2p, *pde;
6293 	pt_entry_t *l3p, *tl3p;
6294 	vm_page_t mt;
6295 	vm_paddr_t pa;
6296 	vm_pindex_t l2pindex;
6297 	int lvl;
6298 
6299 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
6300 	KASSERT((va & L3C_OFFSET) == 0,
6301 	    ("pmap_enter_l3c: va is not aligned"));
6302 	KASSERT(!VA_IS_CLEANMAP(va) || (l3e & ATTR_SW_MANAGED) == 0,
6303 	    ("pmap_enter_l3c: managed mapping within the clean submap"));
6304 	KASSERT((l3e & ATTR_CONTIGUOUS) != 0,
6305 	    ("pmap_enter_l3c: l3e is missing ATTR_CONTIGUOUS"));
6306 
6307 	/*
6308 	 * If the L3 PTP is not resident, we attempt to create it here.
6309 	 */
6310 	if (ADDR_IS_USER(va)) {
6311 		/*
6312 		 * Were we given the correct L3 PTP?  If so, we can simply
6313 		 * increment its ref count.
6314 		 */
6315 		l2pindex = pmap_l2_pindex(va);
6316 		if (*ml3p != NULL && (*ml3p)->pindex == l2pindex) {
6317 			(*ml3p)->ref_count += L3C_ENTRIES;
6318 		} else {
6319 retry:
6320 			/*
6321 			 * Get the L2 entry.
6322 			 */
6323 			pde = pmap_pde(pmap, va, &lvl);
6324 
6325 			/*
6326 			 * If the L2 entry is a superpage, we either abort or
6327 			 * demote depending on the given flags.
6328 			 */
6329 			if (lvl == 1) {
6330 				l2p = pmap_l1_to_l2(pde, va);
6331 				if ((pmap_load(l2p) & ATTR_DESCR_MASK) ==
6332 				    L2_BLOCK) {
6333 					if ((flags & PMAP_ENTER_NOREPLACE) != 0)
6334 						return (KERN_FAILURE);
6335 					l3p = pmap_demote_l2_locked(pmap, l2p,
6336 					    va, lockp);
6337 					if (l3p != NULL) {
6338 						*ml3p = PTE_TO_VM_PAGE(
6339 						    pmap_load(l2p));
6340 						(*ml3p)->ref_count +=
6341 						    L3C_ENTRIES;
6342 						goto have_l3p;
6343 					}
6344 				}
6345 				/* We need to allocate an L3 PTP. */
6346 			}
6347 
6348 			/*
6349 			 * If the L3 PTP is mapped, we just increment its ref
6350 			 * count.  Otherwise, we attempt to allocate it.
6351 			 */
6352 			if (lvl == 2 && pmap_load(pde) != 0) {
6353 				*ml3p = PTE_TO_VM_PAGE(pmap_load(pde));
6354 				(*ml3p)->ref_count += L3C_ENTRIES;
6355 			} else {
6356 				*ml3p = _pmap_alloc_l3(pmap, l2pindex, (flags &
6357 				    PMAP_ENTER_NOSLEEP) != 0 ? NULL : lockp);
6358 				if (*ml3p == NULL) {
6359 					if ((flags & PMAP_ENTER_NOSLEEP) != 0)
6360 						return (KERN_FAILURE);
6361 
6362 					/*
6363 					 * The page table may have changed
6364 					 * while we slept.
6365 					 */
6366 					goto retry;
6367 				}
6368 				(*ml3p)->ref_count += L3C_ENTRIES - 1;
6369 			}
6370 		}
6371 		l3p = VM_PAGE_TO_DMAP(*ml3p);
6372 	} else {
6373 		*ml3p = NULL;
6374 
6375 		/*
6376 		 * If the L2 entry is a superpage, we either abort or demote
6377 		 * depending on the given flags.
6378 		 */
6379 		pde = pmap_pde(kernel_pmap, va, &lvl);
6380 		if (lvl == 1) {
6381 			l2p = pmap_l1_to_l2(pde, va);
6382 			KASSERT((pmap_load(l2p) & ATTR_DESCR_MASK) == L2_BLOCK,
6383 			    ("pmap_enter_l3c: missing L2 block"));
6384 			if ((flags & PMAP_ENTER_NOREPLACE) != 0)
6385 				return (KERN_FAILURE);
6386 			l3p = pmap_demote_l2_locked(pmap, l2p, va, lockp);
6387 		} else {
6388 			KASSERT(lvl == 2,
6389 			    ("pmap_enter_l3c: Invalid level %d", lvl));
6390 			l3p = PHYS_TO_DMAP(PTE_TO_PHYS(pmap_load(pde)));
6391 		}
6392 	}
6393 have_l3p:
6394 	l3p = &l3p[pmap_l3_index(va)];
6395 
6396 	/*
6397 	 * If bti is not the same for the whole L3C range, return failure
6398 	 * and let vm_fault() cope.  Check after L3 allocation, since
6399 	 * it could sleep.
6400 	 */
6401 	if (!pmap_bti_same(pmap, va, va + L3C_SIZE, &l3e)) {
6402 		KASSERT(*ml3p != NULL, ("pmap_enter_l3c: missing L3 PTP"));
6403 		(*ml3p)->ref_count -= L3C_ENTRIES - 1;
6404 		pmap_abort_ptp(pmap, va, *ml3p);
6405 		*ml3p = NULL;
6406 		return (KERN_PROTECTION_FAILURE);
6407 	}
6408 
6409 	/*
6410 	 * If there are existing mappings, either abort or remove them.
6411 	 */
6412 	if ((flags & PMAP_ENTER_NOREPLACE) != 0) {
6413 		for (tl3p = l3p; tl3p < &l3p[L3C_ENTRIES]; tl3p++) {
6414 			if (pmap_load(tl3p) != 0) {
6415 				if (*ml3p != NULL)
6416 					(*ml3p)->ref_count -= L3C_ENTRIES;
6417 				return (KERN_FAILURE);
6418 			}
6419 		}
6420 	} else {
6421 		/*
6422 		 * Because we increment the L3 page's reference count above,
6423 		 * it is guaranteed not to be freed here and we can pass NULL
6424 		 * instead of a valid free list.
6425 		 */
6426 		pmap_remove_l3_range(pmap, pmap_load(pmap_l2(pmap, va)), va,
6427 		    va + L3C_SIZE, NULL, lockp);
6428 	}
6429 
6430 	/*
6431 	 * Enter on the PV list if part of our managed memory.
6432 	 */
6433 	if ((l3e & ATTR_SW_MANAGED) != 0) {
6434 		if (!pmap_pv_insert_l3c(pmap, va, m, lockp)) {
6435 			if (*ml3p != NULL) {
6436 				(*ml3p)->ref_count -= L3C_ENTRIES - 1;
6437 				pmap_abort_ptp(pmap, va, *ml3p);
6438 				*ml3p = NULL;
6439 			}
6440 			return (KERN_RESOURCE_SHORTAGE);
6441 		}
6442 		if ((l3e & ATTR_SW_DBM) != 0)
6443 			for (mt = m; mt < &m[L3C_ENTRIES]; mt++)
6444 				vm_page_aflag_set(mt, PGA_WRITEABLE);
6445 	}
6446 
6447 	/*
6448 	 * Increment counters.
6449 	 */
6450 	if ((l3e & ATTR_SW_WIRED) != 0)
6451 		pmap->pm_stats.wired_count += L3C_ENTRIES;
6452 	pmap_resident_count_inc(pmap, L3C_ENTRIES);
6453 
6454 	pa = VM_PAGE_TO_PHYS(m);
6455 	KASSERT((pa & L3C_OFFSET) == 0, ("pmap_enter_l3c: pa is not aligned"));
6456 
6457 	/*
6458 	 * Sync the icache before the mapping is stored.
6459 	 */
6460 	if ((l3e & ATTR_S1_UXN) == 0 && pmap != kernel_pmap &&
6461 	    m->md.pv_memattr == VM_MEMATTR_WRITE_BACK)
6462 		cpu_icache_sync_range(PHYS_TO_DMAP(pa), L3C_SIZE);
6463 
6464 	/*
6465 	 * Map the superpage.
6466 	 */
6467 	for (tl3p = l3p; tl3p < &l3p[L3C_ENTRIES]; tl3p++) {
6468 		pmap_store(tl3p, l3e);
6469 		l3e += L3_SIZE;
6470 	}
6471 	dsb(ishst);
6472 
6473 	counter_u64_add(pmap_l3c_mappings, 1);
6474 	CTR2(KTR_PMAP, "pmap_enter_l3c: success for va %#lx in pmap %p",
6475 	    va, pmap);
6476 	return (KERN_SUCCESS);
6477 }
6478 
6479 /*
6480  * Maps a sequence of resident pages belonging to the same object.
6481  * The sequence begins with the given page m_start.  This page is
6482  * mapped at the given virtual address start.  Each subsequent page is
6483  * mapped at a virtual address that is offset from start by the same
6484  * amount as the page is offset from m_start within the object.  The
6485  * last page in the sequence is the page with the largest offset from
6486  * m_start that can be mapped at a virtual address less than the given
6487  * virtual address end.  Not every virtual page between start and end
6488  * is mapped; only those for which a resident page exists with the
6489  * corresponding offset from m_start are mapped.
6490  */
6491 void
6492 pmap_enter_object(pmap_t pmap, vm_offset_t start, vm_offset_t end,
6493     vm_page_t m_start, vm_prot_t prot)
6494 {
6495 	struct pctrie_iter pages;
6496 	struct rwlock *lock;
6497 	vm_offset_t va;
6498 	vm_page_t m, mpte;
6499 	int rv;
6500 
6501 	VM_OBJECT_ASSERT_LOCKED(m_start->object);
6502 
6503 	mpte = NULL;
6504 	vm_page_iter_limit_init(&pages, m_start->object,
6505 	    m_start->pindex + atop(end - start));
6506 	m = vm_radix_iter_lookup(&pages, m_start->pindex);
6507 	lock = NULL;
6508 	PMAP_LOCK(pmap);
6509 	while (m != NULL) {
6510 		va = start + ptoa(m->pindex - m_start->pindex);
6511 		if ((va & L2_OFFSET) == 0 && va + L2_SIZE <= end &&
6512 		    m->psind == 2 && pmap_ps_enabled(pmap) &&
6513 		    ((rv = pmap_enter_l2_rx(pmap, va, m, prot, &lock)) ==
6514 		    KERN_SUCCESS || rv == KERN_NO_SPACE)) {
6515 			m = vm_radix_iter_jump(&pages, L2_SIZE / PAGE_SIZE);
6516 		} else if ((va & L3C_OFFSET) == 0 && va + L3C_SIZE <= end &&
6517 		    m->psind >= 1 && pmap_ps_enabled(pmap) &&
6518 		    ((rv = pmap_enter_l3c_rx(pmap, va, m, &mpte, prot,
6519 		    &lock)) == KERN_SUCCESS || rv == KERN_NO_SPACE)) {
6520 			m = vm_radix_iter_jump(&pages, L3C_ENTRIES);
6521 		} else {
6522 			/*
6523 			 * In general, if a superpage mapping were possible,
6524 			 * it would have been created above.  That said, if
6525 			 * start and end are not superpage aligned, then
6526 			 * promotion might be possible at the ends of [start,
6527 			 * end).  However, in practice, those promotion
6528 			 * attempts are so unlikely to succeed that they are
6529 			 * not worth trying.
6530 			 */
6531 			mpte = pmap_enter_quick_locked(pmap, va, m, prot |
6532 			    VM_PROT_NO_PROMOTE, mpte, &lock);
6533 			m = vm_radix_iter_step(&pages);
6534 		}
6535 	}
6536 	if (lock != NULL)
6537 		rw_wunlock(lock);
6538 	PMAP_UNLOCK(pmap);
6539 }
6540 
6541 /*
6542  * this code makes some *MAJOR* assumptions:
6543  * 1. Current pmap & pmap exists.
6544  * 2. Not wired.
6545  * 3. Read access.
6546  * 4. No page table pages.
6547  * but is *MUCH* faster than pmap_enter...
6548  */
6549 
6550 void
6551 pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot)
6552 {
6553 	struct rwlock *lock;
6554 
6555 	lock = NULL;
6556 	PMAP_LOCK(pmap);
6557 	(void)pmap_enter_quick_locked(pmap, va, m, prot, NULL, &lock);
6558 	if (lock != NULL)
6559 		rw_wunlock(lock);
6560 	PMAP_UNLOCK(pmap);
6561 }
6562 
6563 static vm_page_t
6564 pmap_enter_quick_locked(pmap_t pmap, vm_offset_t va, vm_page_t m,
6565     vm_prot_t prot, vm_page_t mpte, struct rwlock **lockp)
6566 {
6567 	pt_entry_t *l1, *l2, *l3, l3_val;
6568 	vm_paddr_t pa;
6569 	int full_lvl, lvl;
6570 
6571 	KASSERT(!VA_IS_CLEANMAP(va) ||
6572 	    (m->oflags & VPO_UNMANAGED) != 0,
6573 	    ("pmap_enter_quick_locked: managed mapping within the clean submap"));
6574 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
6575 	PMAP_ASSERT_STAGE1(pmap);
6576 	KASSERT(ADDR_IS_CANONICAL(va),
6577 	    ("%s: Address not in canonical form: %lx", __func__, va));
6578 	l2 = NULL;
6579 
6580 	CTR2(KTR_PMAP, "pmap_enter_quick_locked: %p %lx", pmap, va);
6581 	/*
6582 	 * In the case that a page table page is not
6583 	 * resident, we are creating it here.
6584 	 */
6585 	if (ADDR_IS_USER(va)) {
6586 		vm_pindex_t l2pindex;
6587 
6588 		/*
6589 		 * Calculate pagetable page index
6590 		 */
6591 		l2pindex = pmap_l2_pindex(va);
6592 		if (mpte && (mpte->pindex == l2pindex)) {
6593 			mpte->ref_count++;
6594 		} else {
6595 			/*
6596 			 * If the page table page is mapped, we just increment
6597 			 * the hold count, and activate it.  Otherwise, we
6598 			 * attempt to allocate a page table page, passing NULL
6599 			 * instead of the PV list lock pointer because we don't
6600 			 * intend to sleep.  If this attempt fails, we don't
6601 			 * retry.  Instead, we give up.
6602 			 */
6603 			l1 = pmap_l1(pmap, va);
6604 			if (l1 != NULL && pmap_load(l1) != 0) {
6605 				if ((pmap_load(l1) & ATTR_DESCR_MASK) ==
6606 				    L1_BLOCK)
6607 					return (NULL);
6608 				l2 = pmap_l1_to_l2(l1, va);
6609 				if (pmap_load(l2) != 0) {
6610 					if ((pmap_load(l2) & ATTR_DESCR_MASK) ==
6611 					    L2_BLOCK)
6612 						return (NULL);
6613 					mpte = PTE_TO_VM_PAGE(pmap_load(l2));
6614 					mpte->ref_count++;
6615 				} else {
6616 					mpte = _pmap_alloc_l3(pmap, l2pindex,
6617 					    NULL);
6618 					if (mpte == NULL)
6619 						return (mpte);
6620 				}
6621 			} else {
6622 				mpte = _pmap_alloc_l3(pmap, l2pindex, NULL);
6623 				if (mpte == NULL)
6624 					return (mpte);
6625 			}
6626 		}
6627 		l3 = VM_PAGE_TO_DMAP(mpte);
6628 		l3 = &l3[pmap_l3_index(va)];
6629 	} else {
6630 		mpte = NULL;
6631 		l2 = pmap_pde(kernel_pmap, va, &lvl);
6632 		KASSERT(l2 != NULL,
6633 		    ("pmap_enter_quick_locked: Invalid page entry, va: 0x%lx",
6634 		     va));
6635 		KASSERT(lvl == 2,
6636 		    ("pmap_enter_quick_locked: Invalid level %d", lvl));
6637 		l3 = pmap_l2_to_l3(l2, va);
6638 	}
6639 
6640 	/*
6641 	 * Abort if a mapping already exists.
6642 	 */
6643 	if (pmap_load(l3) != 0) {
6644 		if (mpte != NULL)
6645 			mpte->ref_count--;
6646 		return (NULL);
6647 	}
6648 
6649 	/*
6650 	 * Enter on the PV list if part of our managed memory.
6651 	 */
6652 	if ((m->oflags & VPO_UNMANAGED) == 0 &&
6653 	    !pmap_try_insert_pv_entry(pmap, va, m, lockp)) {
6654 		if (mpte != NULL)
6655 			pmap_abort_ptp(pmap, va, mpte);
6656 		return (NULL);
6657 	}
6658 
6659 	/*
6660 	 * Increment counters
6661 	 */
6662 	pmap_resident_count_inc(pmap, 1);
6663 
6664 	pa = VM_PAGE_TO_PHYS(m);
6665 	l3_val = PHYS_TO_PTE(pa) | pmap_sh_attr |
6666 	    ATTR_S1_IDX(m->md.pv_memattr) | ATTR_S1_AP(ATTR_S1_AP_RO) | L3_PAGE;
6667 	l3_val |= pmap_pte_bti(pmap, va);
6668 	if ((prot & VM_PROT_EXECUTE) == 0 ||
6669 	    m->md.pv_memattr == VM_MEMATTR_DEVICE)
6670 		l3_val |= ATTR_S1_XN;
6671 	if (ADDR_IS_USER(va))
6672 		l3_val |= ATTR_S1_AP(ATTR_S1_AP_USER) | ATTR_S1_PXN;
6673 	else
6674 		l3_val |= ATTR_S1_UXN;
6675 	if (pmap != kernel_pmap)
6676 		l3_val |= ATTR_S1_nG;
6677 
6678 	/*
6679 	 * Now validate mapping with RO protection
6680 	 */
6681 	if ((m->oflags & VPO_UNMANAGED) == 0)
6682 		l3_val |= ATTR_SW_MANAGED;
6683 	else
6684 		l3_val |= ATTR_AF;
6685 
6686 	/* Sync icache before the mapping is stored to PTE */
6687 	if ((prot & VM_PROT_EXECUTE) && pmap != kernel_pmap &&
6688 	    m->md.pv_memattr == VM_MEMATTR_WRITE_BACK)
6689 		cpu_icache_sync_range(PHYS_TO_DMAP(pa), PAGE_SIZE);
6690 
6691 	pmap_store(l3, l3_val);
6692 	dsb(ishst);
6693 
6694 #if VM_NRESERVLEVEL > 0
6695 	/*
6696 	 * First, attempt L3C promotion, if the virtual and physical addresses
6697 	 * are aligned with each other and an underlying reservation has the
6698 	 * neighboring L3 pages allocated.  The first condition is simply an
6699 	 * optimization that recognizes some eventual promotion failures early
6700 	 * at a lower run-time cost.  Then, attempt L2 promotion, if both a
6701 	 * level 1 reservation and the PTP are fully populated.
6702 	 */
6703 	if ((prot & VM_PROT_NO_PROMOTE) == 0 &&
6704 	    (va & L3C_OFFSET) == (pa & L3C_OFFSET) &&
6705 	    (m->flags & PG_FICTITIOUS) == 0 &&
6706 	    (full_lvl = vm_reserv_level_iffullpop(m)) >= 0 &&
6707 	    pmap_promote_l3c(pmap, l3, va) &&
6708 	    full_lvl == 1 && (mpte == NULL || mpte->ref_count == NL3PG)) {
6709 		if (l2 == NULL)
6710 			l2 = pmap_l2(pmap, va);
6711 
6712 		/*
6713 		 * If promotion succeeds, then the next call to this function
6714 		 * should not be given the unmapped PTP as a hint.
6715 		 */
6716 		if (pmap_promote_l2(pmap, l2, va, mpte, lockp))
6717 			mpte = NULL;
6718 	}
6719 #endif
6720 
6721 	return (mpte);
6722 }
6723 
6724 /*
6725  * This code maps large physical mmap regions into the
6726  * processor address space.  Note that some shortcuts
6727  * are taken, but the code works.
6728  */
6729 void
6730 pmap_object_init_pt(pmap_t pmap, vm_offset_t addr, vm_object_t object,
6731     vm_pindex_t pindex, vm_size_t size)
6732 {
6733 
6734 	VM_OBJECT_ASSERT_WLOCKED(object);
6735 	KASSERT(object->type == OBJT_DEVICE || object->type == OBJT_SG,
6736 	    ("pmap_object_init_pt: non-device object"));
6737 }
6738 
6739 /*
6740  *	Clear the wired attribute from the mappings for the specified range of
6741  *	addresses in the given pmap.  Every valid mapping within that range
6742  *	must have the wired attribute set.  In contrast, invalid mappings
6743  *	cannot have the wired attribute set, so they are ignored.
6744  *
6745  *	The wired attribute of the page table entry is not a hardware feature,
6746  *	so there is no need to invalidate any TLB entries.
6747  */
6748 void
6749 pmap_unwire(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
6750 {
6751 	vm_offset_t va_next;
6752 	pd_entry_t *l0, *l1, *l2;
6753 	pt_entry_t *l3;
6754 	bool partial_l3c;
6755 
6756 	PMAP_LOCK(pmap);
6757 	for (; sva < eva; sva = va_next) {
6758 		l0 = pmap_l0(pmap, sva);
6759 		if (pmap_load(l0) == 0) {
6760 			va_next = (sva + L0_SIZE) & ~L0_OFFSET;
6761 			if (va_next < sva)
6762 				va_next = eva;
6763 			continue;
6764 		}
6765 
6766 		l1 = pmap_l0_to_l1(l0, sva);
6767 		va_next = (sva + L1_SIZE) & ~L1_OFFSET;
6768 		if (va_next < sva)
6769 			va_next = eva;
6770 		if (pmap_load(l1) == 0)
6771 			continue;
6772 
6773 		if ((pmap_load(l1) & ATTR_DESCR_MASK) == L1_BLOCK) {
6774 			PMAP_ASSERT_L1_BLOCKS_SUPPORTED;
6775 			KASSERT(va_next <= eva,
6776 			    ("partial update of non-transparent 1G page "
6777 			    "l1 %#lx sva %#lx eva %#lx va_next %#lx",
6778 			    pmap_load(l1), sva, eva, va_next));
6779 			MPASS(pmap != kernel_pmap);
6780 			MPASS((pmap_load(l1) & (ATTR_SW_MANAGED |
6781 			    ATTR_SW_WIRED)) == ATTR_SW_WIRED);
6782 			pmap_clear_bits(l1, ATTR_SW_WIRED);
6783 			pmap->pm_stats.wired_count -= L1_SIZE / PAGE_SIZE;
6784 			continue;
6785 		}
6786 
6787 		va_next = (sva + L2_SIZE) & ~L2_OFFSET;
6788 		if (va_next < sva)
6789 			va_next = eva;
6790 
6791 		l2 = pmap_l1_to_l2(l1, sva);
6792 		if (pmap_load(l2) == 0)
6793 			continue;
6794 
6795 		if ((pmap_load(l2) & ATTR_DESCR_MASK) == L2_BLOCK) {
6796 			if ((pmap_load(l2) & ATTR_SW_WIRED) == 0)
6797 				panic("pmap_unwire: l2 %#jx is missing "
6798 				    "ATTR_SW_WIRED", (uintmax_t)pmap_load(l2));
6799 
6800 			/*
6801 			 * Are we unwiring the entire large page?  If not,
6802 			 * demote the mapping and fall through.
6803 			 */
6804 			if (sva + L2_SIZE == va_next && eva >= va_next) {
6805 				pmap_clear_bits(l2, ATTR_SW_WIRED);
6806 				pmap->pm_stats.wired_count -= L2_SIZE /
6807 				    PAGE_SIZE;
6808 				continue;
6809 			} else if (pmap_demote_l2(pmap, l2, sva) == NULL)
6810 				panic("pmap_unwire: demotion failed");
6811 		}
6812 		KASSERT((pmap_load(l2) & ATTR_DESCR_MASK) == L2_TABLE,
6813 		    ("pmap_unwire: Invalid l2 entry after demotion"));
6814 
6815 		if (va_next > eva)
6816 			va_next = eva;
6817 		for (partial_l3c = true, l3 = pmap_l2_to_l3(l2, sva);
6818 		    sva != va_next; l3++, sva += L3_SIZE) {
6819 			if (pmap_load(l3) == 0)
6820 				continue;
6821 			if ((pmap_load(l3) & ATTR_CONTIGUOUS) != 0) {
6822 				/*
6823 				 * Avoid demotion for whole-page unwiring.
6824 				 */
6825 				if ((sva & L3C_OFFSET) == 0) {
6826 					/*
6827 					 * Handle the possibility that
6828 					 * "va_next" is zero because of
6829 					 * address wraparound.
6830 					 */
6831 					partial_l3c = sva + L3C_OFFSET >
6832 					    va_next - 1;
6833 				}
6834 				if (partial_l3c)
6835 					(void)pmap_demote_l3c(pmap, l3, sva);
6836 			}
6837 			if ((pmap_load(l3) & ATTR_SW_WIRED) == 0)
6838 				panic("pmap_unwire: l3 %#jx is missing "
6839 				    "ATTR_SW_WIRED", (uintmax_t)pmap_load(l3));
6840 
6841 			/*
6842 			 * ATTR_SW_WIRED must be cleared atomically.  Although
6843 			 * the pmap lock synchronizes access to ATTR_SW_WIRED,
6844 			 * the System MMU may write to the entry concurrently.
6845 			 */
6846 			pmap_clear_bits(l3, ATTR_SW_WIRED);
6847 			pmap->pm_stats.wired_count--;
6848 		}
6849 	}
6850 	PMAP_UNLOCK(pmap);
6851 }
6852 
6853 /*
6854  * This function requires that the caller has already added one to ml3's
6855  * ref_count in anticipation of creating a 4KB page mapping.
6856  */
6857 static bool
6858 pmap_copy_l3c(pmap_t pmap, pt_entry_t *l3p, vm_offset_t va, pt_entry_t l3e,
6859     vm_page_t ml3, struct rwlock **lockp)
6860 {
6861 	pt_entry_t *tl3p;
6862 
6863 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
6864 	KASSERT((va & L3C_OFFSET) == 0,
6865 	    ("pmap_copy_l3c: va is not aligned"));
6866 	KASSERT((l3e & ATTR_SW_MANAGED) != 0,
6867 	    ("pmap_copy_l3c: l3e is not managed"));
6868 
6869 	/*
6870 	 * Abort if a mapping already exists.
6871 	 */
6872 	for (tl3p = l3p; tl3p < &l3p[L3C_ENTRIES]; tl3p++)
6873 		if (pmap_load(tl3p) != 0) {
6874 			if (ml3 != NULL)
6875 				ml3->ref_count--;
6876 			return (false);
6877 		}
6878 
6879 	if (!pmap_pv_insert_l3c(pmap, va, PTE_TO_VM_PAGE(l3e), lockp)) {
6880 		if (ml3 != NULL)
6881 			pmap_abort_ptp(pmap, va, ml3);
6882 		return (false);
6883 	}
6884 	ml3->ref_count += L3C_ENTRIES - 1;
6885 
6886 	/*
6887 	 * Clear the wired and accessed bits.  However, leave the dirty bit
6888 	 * unchanged because read/write superpage mappings are required to be
6889 	 * dirty.
6890 	 */
6891 	l3e &= ~(ATTR_SW_WIRED | ATTR_AF);
6892 
6893 	for (tl3p = l3p; tl3p < &l3p[L3C_ENTRIES]; tl3p++) {
6894 		pmap_store(tl3p, l3e);
6895 		l3e += L3_SIZE;
6896 	}
6897 	pmap_resident_count_inc(pmap, L3C_ENTRIES);
6898 	counter_u64_add(pmap_l3c_mappings, 1);
6899 	CTR2(KTR_PMAP, "pmap_copy_l3c: success for va %#lx in pmap %p",
6900 	    va, pmap);
6901 	return (true);
6902 }
6903 
6904 /*
6905  *	Copy the range specified by src_addr/len
6906  *	from the source map to the range dst_addr/len
6907  *	in the destination map.
6908  *
6909  *	This routine is only advisory and need not do anything.
6910  *
6911  *	Because the executable mappings created by this routine are copied,
6912  *	it should not have to flush the instruction cache.
6913  */
6914 void
6915 pmap_copy(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr, vm_size_t len,
6916     vm_offset_t src_addr)
6917 {
6918 	struct rwlock *lock;
6919 	pd_entry_t *l0, *l1, *l2, srcptepaddr;
6920 	pt_entry_t *dst_pte, mask, nbits, ptetemp, *src_pte;
6921 	vm_offset_t addr, end_addr, va_next;
6922 	vm_page_t dst_m, dstmpte, srcmpte;
6923 
6924 	PMAP_ASSERT_STAGE1(dst_pmap);
6925 	PMAP_ASSERT_STAGE1(src_pmap);
6926 
6927 	if (dst_addr != src_addr)
6928 		return;
6929 	end_addr = src_addr + len;
6930 	lock = NULL;
6931 	if (dst_pmap < src_pmap) {
6932 		PMAP_LOCK(dst_pmap);
6933 		PMAP_LOCK(src_pmap);
6934 	} else {
6935 		PMAP_LOCK(src_pmap);
6936 		PMAP_LOCK(dst_pmap);
6937 	}
6938 	for (addr = src_addr; addr < end_addr; addr = va_next) {
6939 		l0 = pmap_l0(src_pmap, addr);
6940 		if (pmap_load(l0) == 0) {
6941 			va_next = (addr + L0_SIZE) & ~L0_OFFSET;
6942 			if (va_next < addr)
6943 				va_next = end_addr;
6944 			continue;
6945 		}
6946 
6947 		va_next = (addr + L1_SIZE) & ~L1_OFFSET;
6948 		if (va_next < addr)
6949 			va_next = end_addr;
6950 		l1 = pmap_l0_to_l1(l0, addr);
6951 		if (pmap_load(l1) == 0)
6952 			continue;
6953 		if ((pmap_load(l1) & ATTR_DESCR_MASK) == L1_BLOCK) {
6954 			PMAP_ASSERT_L1_BLOCKS_SUPPORTED;
6955 			KASSERT(va_next <= end_addr,
6956 			    ("partial update of non-transparent 1G page "
6957 			    "l1 %#lx addr %#lx end_addr %#lx va_next %#lx",
6958 			    pmap_load(l1), addr, end_addr, va_next));
6959 			srcptepaddr = pmap_load(l1);
6960 			l1 = pmap_l1(dst_pmap, addr);
6961 			if (l1 == NULL) {
6962 				if (_pmap_alloc_l3(dst_pmap,
6963 				    pmap_l0_pindex(addr), NULL) == NULL)
6964 					break;
6965 				l1 = pmap_l1(dst_pmap, addr);
6966 			} else {
6967 				l0 = pmap_l0(dst_pmap, addr);
6968 				dst_m = PTE_TO_VM_PAGE(pmap_load(l0));
6969 				dst_m->ref_count++;
6970 			}
6971 			KASSERT(pmap_load(l1) == 0,
6972 			    ("1G mapping present in dst pmap "
6973 			    "l1 %#lx addr %#lx end_addr %#lx va_next %#lx",
6974 			    pmap_load(l1), addr, end_addr, va_next));
6975 			pmap_store(l1, srcptepaddr & ~ATTR_SW_WIRED);
6976 			pmap_resident_count_inc(dst_pmap, L1_SIZE / PAGE_SIZE);
6977 			continue;
6978 		}
6979 
6980 		va_next = (addr + L2_SIZE) & ~L2_OFFSET;
6981 		if (va_next < addr)
6982 			va_next = end_addr;
6983 		l2 = pmap_l1_to_l2(l1, addr);
6984 		srcptepaddr = pmap_load(l2);
6985 		if (srcptepaddr == 0)
6986 			continue;
6987 		if ((srcptepaddr & ATTR_DESCR_MASK) == L2_BLOCK) {
6988 			/*
6989 			 * We can only virtual copy whole superpages.
6990 			 */
6991 			if ((addr & L2_OFFSET) != 0 ||
6992 			    addr + L2_SIZE > end_addr)
6993 				continue;
6994 			l2 = pmap_alloc_l2(dst_pmap, addr, &dst_m, NULL);
6995 			if (l2 == NULL)
6996 				break;
6997 			if (pmap_load(l2) == 0 &&
6998 			    ((srcptepaddr & ATTR_SW_MANAGED) == 0 ||
6999 			    pmap_pv_insert_l2(dst_pmap, addr, srcptepaddr,
7000 			    PMAP_ENTER_NORECLAIM, &lock))) {
7001 				/*
7002 				 * We leave the dirty bit unchanged because
7003 				 * managed read/write superpage mappings are
7004 				 * required to be dirty.  However, managed
7005 				 * superpage mappings are not required to
7006 				 * have their accessed bit set, so we clear
7007 				 * it because we don't know if this mapping
7008 				 * will be used.
7009 				 */
7010 				srcptepaddr &= ~ATTR_SW_WIRED;
7011 				if ((srcptepaddr & ATTR_SW_MANAGED) != 0)
7012 					srcptepaddr &= ~ATTR_AF;
7013 				pmap_store(l2, srcptepaddr);
7014 				pmap_resident_count_inc(dst_pmap, L2_SIZE /
7015 				    PAGE_SIZE);
7016 				counter_u64_add(pmap_l2_mappings, 1);
7017 			} else
7018 				pmap_abort_ptp(dst_pmap, addr, dst_m);
7019 			continue;
7020 		}
7021 		KASSERT((srcptepaddr & ATTR_DESCR_MASK) == L2_TABLE,
7022 		    ("pmap_copy: invalid L2 entry"));
7023 		srcmpte = PTE_TO_VM_PAGE(srcptepaddr);
7024 		KASSERT(srcmpte->ref_count > 0,
7025 		    ("pmap_copy: source page table page is unused"));
7026 		if (va_next > end_addr)
7027 			va_next = end_addr;
7028 		src_pte = PHYS_TO_DMAP(PTE_TO_PHYS(srcptepaddr));
7029 		src_pte = &src_pte[pmap_l3_index(addr)];
7030 		dstmpte = NULL;
7031 		for (; addr < va_next; addr += PAGE_SIZE, src_pte++) {
7032 			ptetemp = pmap_load(src_pte);
7033 
7034 			/*
7035 			 * We only virtual copy managed pages.
7036 			 */
7037 			if ((ptetemp & ATTR_SW_MANAGED) == 0)
7038 				continue;
7039 
7040 			if (dstmpte != NULL) {
7041 				KASSERT(dstmpte->pindex == pmap_l2_pindex(addr),
7042 				    ("dstmpte pindex/addr mismatch"));
7043 				dstmpte->ref_count++;
7044 			} else if ((dstmpte = pmap_alloc_l3(dst_pmap, addr,
7045 			    NULL)) == NULL)
7046 				goto out;
7047 			dst_pte = VM_PAGE_TO_DMAP(dstmpte);
7048 			dst_pte = &dst_pte[pmap_l3_index(addr)];
7049 			if ((ptetemp & ATTR_CONTIGUOUS) != 0 && (addr &
7050 			    L3C_OFFSET) == 0 && addr + L3C_OFFSET <=
7051 			    va_next - 1) {
7052 				if (!pmap_copy_l3c(dst_pmap, dst_pte, addr,
7053 				    ptetemp, dstmpte, &lock))
7054 					goto out;
7055 				addr += L3C_SIZE - PAGE_SIZE;
7056 				src_pte += L3C_ENTRIES - 1;
7057 			} else if (pmap_load(dst_pte) == 0 &&
7058 			    pmap_try_insert_pv_entry(dst_pmap, addr,
7059 			    PTE_TO_VM_PAGE(ptetemp), &lock)) {
7060 				/*
7061 				 * Clear the wired, contiguous, modified, and
7062 				 * accessed bits from the destination PTE.
7063 				 * The contiguous bit is cleared because we
7064 				 * are not copying the entire L3C superpage.
7065 				 */
7066 				mask = ATTR_SW_WIRED | ATTR_CONTIGUOUS |
7067 				    ATTR_AF;
7068 				nbits = 0;
7069 				if ((ptetemp & ATTR_SW_DBM) != 0)
7070 					nbits |= ATTR_S1_AP_RW_BIT;
7071 				pmap_store(dst_pte, (ptetemp & ~mask) | nbits);
7072 				pmap_resident_count_inc(dst_pmap, 1);
7073 			} else {
7074 				pmap_abort_ptp(dst_pmap, addr, dstmpte);
7075 				goto out;
7076 			}
7077 			/* Have we copied all of the valid mappings? */
7078 			if (dstmpte->ref_count >= srcmpte->ref_count)
7079 				break;
7080 		}
7081 	}
7082 out:
7083 	/*
7084 	 * XXX This barrier may not be needed because the destination pmap is
7085 	 * not active.
7086 	 */
7087 	dsb(ishst);
7088 
7089 	if (lock != NULL)
7090 		rw_wunlock(lock);
7091 	PMAP_UNLOCK(src_pmap);
7092 	PMAP_UNLOCK(dst_pmap);
7093 }
7094 
7095 int
7096 pmap_vmspace_copy(pmap_t dst_pmap, pmap_t src_pmap)
7097 {
7098 	int error;
7099 
7100 	if (dst_pmap->pm_stage != src_pmap->pm_stage)
7101 		return (EINVAL);
7102 
7103 	if (dst_pmap->pm_stage != PM_STAGE1 || src_pmap->pm_bti == NULL)
7104 		return (0);
7105 
7106 	for (;;) {
7107 		if (dst_pmap < src_pmap) {
7108 			PMAP_LOCK(dst_pmap);
7109 			PMAP_LOCK(src_pmap);
7110 		} else {
7111 			PMAP_LOCK(src_pmap);
7112 			PMAP_LOCK(dst_pmap);
7113 		}
7114 		error = pmap_bti_copy(dst_pmap, src_pmap);
7115 		/* Clean up partial copy on failure due to no memory. */
7116 		if (error == ENOMEM)
7117 			pmap_bti_deassign_all(dst_pmap);
7118 		PMAP_UNLOCK(src_pmap);
7119 		PMAP_UNLOCK(dst_pmap);
7120 		if (error != ENOMEM)
7121 			break;
7122 		vm_wait(NULL);
7123 	}
7124 	return (error);
7125 }
7126 
7127 /*
7128  *	pmap_zero_page zeros the specified hardware page by mapping
7129  *	the page into KVM and using bzero to clear its contents.
7130  */
7131 void
7132 pmap_zero_page(vm_page_t m)
7133 {
7134 	void *va = VM_PAGE_TO_DMAP(m);
7135 
7136 	pagezero(va);
7137 	m->md.pv_flags &= ~PV_MTE_TAGGED;
7138 }
7139 
7140 /*
7141  *	pmap_zero_page_area zeros the specified hardware page by mapping
7142  *	the page into KVM and using bzero to clear its contents.
7143  *
7144  *	off and size may not cover an area beyond a single hardware page.
7145  */
7146 void
7147 pmap_zero_page_area(vm_page_t m, int off, int size)
7148 {
7149 	void *va = VM_PAGE_TO_DMAP(m);
7150 
7151 	if (off == 0 && size == PAGE_SIZE)
7152 		pagezero(va);
7153 	else
7154 		bzero((char *)va + off, size);
7155 }
7156 
7157 /*
7158  *	pmap_copy_page copies the specified (machine independent)
7159  *	page by mapping the page into virtual memory and using
7160  *	memcpy to copy the page, one machine dependent page at a
7161  *	time.
7162  */
7163 void
7164 pmap_copy_page(vm_page_t msrc, vm_page_t mdst)
7165 {
7166 	void *src = VM_PAGE_TO_DMAP(msrc);
7167 	void *dst = VM_PAGE_TO_DMAP(mdst);
7168 
7169 	/*
7170 	 * On a page copy, check whether the src page is tagged. If it is,
7171 	 * we must copy the tags before copying the contents of the page.
7172 	 */
7173 	if ((msrc->md.pv_flags & PV_MTE_TAGGED) != 0)
7174 		mte_copy_tags(msrc, mdst, src, dst);
7175 	else
7176 		mdst->md.pv_flags &= ~PV_MTE_TAGGED;
7177 
7178 	pagecopy(src, dst);
7179 }
7180 
7181 int unmapped_buf_allowed = 1;
7182 
7183 void
7184 pmap_copy_pages(vm_page_t ma[], vm_offset_t a_offset, vm_page_t mb[],
7185     vm_offset_t b_offset, int xfersize)
7186 {
7187 	void *a_cp, *b_cp;
7188 	vm_page_t m_a, m_b;
7189 	vm_paddr_t p_a, p_b;
7190 	vm_offset_t a_pg_offset, b_pg_offset;
7191 	int cnt;
7192 
7193 	while (xfersize > 0) {
7194 		KASSERT(ADDR_IS_CANONICAL(a_offset),
7195 		    ("%s: Address not in canonical form: %lx", __func__, a_offset));
7196 
7197 		a_pg_offset = a_offset & PAGE_MASK;
7198 		m_a = ma[a_offset >> PAGE_SHIFT];
7199 		p_a = m_a->phys_addr;
7200 		b_pg_offset = b_offset & PAGE_MASK;
7201 		m_b = mb[b_offset >> PAGE_SHIFT];
7202 		p_b = m_b->phys_addr;
7203 		cnt = min(xfersize, PAGE_SIZE - a_pg_offset);
7204 		cnt = min(cnt, PAGE_SIZE - b_pg_offset);
7205 		if (__predict_false(!PHYS_IN_DMAP(p_a))) {
7206 			panic("!DMAP a %lx", p_a);
7207 		} else {
7208 			a_cp = (char *)PHYS_TO_DMAP(p_a) + a_pg_offset;
7209 		}
7210 		if (__predict_false(!PHYS_IN_DMAP(p_b))) {
7211 			panic("!DMAP b %lx", p_b);
7212 		} else {
7213 			b_cp = (char *)PHYS_TO_DMAP(p_b) + b_pg_offset;
7214 		}
7215 		memcpy(b_cp, a_cp, cnt);
7216 		a_offset += cnt;
7217 		b_offset += cnt;
7218 		xfersize -= cnt;
7219 	}
7220 }
7221 
7222 void *
7223 pmap_quick_enter_page(vm_page_t m)
7224 {
7225 
7226 	return (VM_PAGE_TO_DMAP(m));
7227 }
7228 
7229 void
7230 pmap_quick_remove_page(void *addr)
7231 {
7232 }
7233 
7234 /*
7235  * Returns true if the pmap's pv is one of the first
7236  * 16 pvs linked to from this page.  This count may
7237  * be changed upwards or downwards in the future; it
7238  * is only necessary that true be returned for a small
7239  * subset of pmaps for proper page aging.
7240  */
7241 bool
7242 pmap_page_exists_quick(pmap_t pmap, vm_page_t m)
7243 {
7244 	struct md_page *pvh;
7245 	struct rwlock *lock;
7246 	pv_entry_t pv;
7247 	int loops = 0;
7248 	bool rv;
7249 
7250 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
7251 	    ("pmap_page_exists_quick: page %p is not managed", m));
7252 	rv = false;
7253 	lock = VM_PAGE_TO_PV_LIST_LOCK(m);
7254 	rw_rlock(lock);
7255 	TAILQ_FOREACH(pv, &m->md.pv_list, pv_next) {
7256 		if (PV_PMAP(pv) == pmap) {
7257 			rv = true;
7258 			break;
7259 		}
7260 		loops++;
7261 		if (loops >= 16)
7262 			break;
7263 	}
7264 	if (!rv && loops < 16 && (m->flags & PG_FICTITIOUS) == 0) {
7265 		pvh = page_to_pvh(m);
7266 		TAILQ_FOREACH(pv, &pvh->pv_list, pv_next) {
7267 			if (PV_PMAP(pv) == pmap) {
7268 				rv = true;
7269 				break;
7270 			}
7271 			loops++;
7272 			if (loops >= 16)
7273 				break;
7274 		}
7275 	}
7276 	rw_runlock(lock);
7277 	return (rv);
7278 }
7279 
7280 /*
7281  *	pmap_page_wired_mappings:
7282  *
7283  *	Return the number of managed mappings to the given physical page
7284  *	that are wired.
7285  */
7286 int
7287 pmap_page_wired_mappings(vm_page_t m)
7288 {
7289 	struct rwlock *lock;
7290 	struct md_page *pvh;
7291 	pmap_t pmap;
7292 	pt_entry_t *pte;
7293 	pv_entry_t pv;
7294 	int count, md_gen, pvh_gen;
7295 
7296 	if ((m->oflags & VPO_UNMANAGED) != 0)
7297 		return (0);
7298 	lock = VM_PAGE_TO_PV_LIST_LOCK(m);
7299 	rw_rlock(lock);
7300 restart:
7301 	count = 0;
7302 	TAILQ_FOREACH(pv, &m->md.pv_list, pv_next) {
7303 		pmap = PV_PMAP(pv);
7304 		if (!PMAP_TRYLOCK(pmap)) {
7305 			md_gen = m->md.pv_gen;
7306 			rw_runlock(lock);
7307 			PMAP_LOCK(pmap);
7308 			rw_rlock(lock);
7309 			if (md_gen != m->md.pv_gen) {
7310 				PMAP_UNLOCK(pmap);
7311 				goto restart;
7312 			}
7313 		}
7314 		pte = pmap_pte_exists(pmap, pv->pv_va, 3, __func__);
7315 		if ((pmap_load(pte) & ATTR_SW_WIRED) != 0)
7316 			count++;
7317 		PMAP_UNLOCK(pmap);
7318 	}
7319 	if ((m->flags & PG_FICTITIOUS) == 0) {
7320 		pvh = page_to_pvh(m);
7321 		TAILQ_FOREACH(pv, &pvh->pv_list, pv_next) {
7322 			pmap = PV_PMAP(pv);
7323 			if (!PMAP_TRYLOCK(pmap)) {
7324 				md_gen = m->md.pv_gen;
7325 				pvh_gen = pvh->pv_gen;
7326 				rw_runlock(lock);
7327 				PMAP_LOCK(pmap);
7328 				rw_rlock(lock);
7329 				if (md_gen != m->md.pv_gen ||
7330 				    pvh_gen != pvh->pv_gen) {
7331 					PMAP_UNLOCK(pmap);
7332 					goto restart;
7333 				}
7334 			}
7335 			pte = pmap_pte_exists(pmap, pv->pv_va, 2, __func__);
7336 			if ((pmap_load(pte) & ATTR_SW_WIRED) != 0)
7337 				count++;
7338 			PMAP_UNLOCK(pmap);
7339 		}
7340 	}
7341 	rw_runlock(lock);
7342 	return (count);
7343 }
7344 
7345 /*
7346  * Returns true if the given page is mapped individually or as part of
7347  * a 2mpage.  Otherwise, returns false.
7348  */
7349 bool
7350 pmap_page_is_mapped(vm_page_t m)
7351 {
7352 	struct rwlock *lock;
7353 	bool rv;
7354 
7355 	if ((m->oflags & VPO_UNMANAGED) != 0)
7356 		return (false);
7357 	lock = VM_PAGE_TO_PV_LIST_LOCK(m);
7358 	rw_rlock(lock);
7359 	rv = pmap_page_is_mapped_locked(m);
7360 	rw_runlock(lock);
7361 	return (rv);
7362 }
7363 
7364 /*
7365  * The page's PV list lock must be held.
7366  */
7367 static __always_inline bool
7368 pmap_page_is_mapped_locked(vm_page_t m)
7369 {
7370 	return (!TAILQ_EMPTY(&m->md.pv_list) ||
7371 	    ((m->flags & PG_FICTITIOUS) == 0 &&
7372 	    !TAILQ_EMPTY(&page_to_pvh(m)->pv_list)));
7373 }
7374 
7375 /*
7376  * Destroy all managed, non-wired mappings in the given user-space
7377  * pmap.  This pmap cannot be active on any processor besides the
7378  * caller.
7379  *
7380  * This function cannot be applied to the kernel pmap.  Moreover, it
7381  * is not intended for general use.  It is only to be used during
7382  * process termination.  Consequently, it can be implemented in ways
7383  * that make it faster than pmap_remove().  First, it can more quickly
7384  * destroy mappings by iterating over the pmap's collection of PV
7385  * entries, rather than searching the page table.  Second, it doesn't
7386  * have to test and clear the page table entries atomically, because
7387  * no processor is currently accessing the user address space.  In
7388  * particular, a page table entry's dirty bit won't change state once
7389  * this function starts.
7390  */
7391 void
7392 pmap_remove_pages(pmap_t pmap)
7393 {
7394 	pd_entry_t *pde;
7395 	pt_entry_t *pte, tpte;
7396 	struct spglist free;
7397 	struct pv_chunklist free_chunks[PMAP_MEMDOM];
7398 	vm_page_t m, ml3, mt;
7399 	pv_entry_t pv;
7400 	struct md_page *pvh;
7401 	struct pv_chunk *pc, *npc;
7402 	struct rwlock *lock;
7403 	int64_t bit;
7404 	uint64_t inuse, bitmask;
7405 	int allfree, field, i, idx, lvl;
7406 	int freed __pvused;
7407 	vm_paddr_t pa;
7408 
7409 	lock = NULL;
7410 
7411 	for (i = 0; i < PMAP_MEMDOM; i++)
7412 		TAILQ_INIT(&free_chunks[i]);
7413 	SLIST_INIT(&free);
7414 	PMAP_LOCK(pmap);
7415 	TAILQ_FOREACH_SAFE(pc, &pmap->pm_pvchunk, pc_list, npc) {
7416 		allfree = 1;
7417 		freed = 0;
7418 		for (field = 0; field < _NPCM; field++) {
7419 			inuse = ~pc->pc_map[field] & pc_freemask[field];
7420 			while (inuse != 0) {
7421 				bit = ffsl(inuse) - 1;
7422 				bitmask = 1UL << bit;
7423 				idx = field * 64 + bit;
7424 				pv = &pc->pc_pventry[idx];
7425 				inuse &= ~bitmask;
7426 
7427 				pde = pmap_pde(pmap, pv->pv_va, &lvl);
7428 				KASSERT(pde != NULL,
7429 				    ("Attempting to remove an unmapped page"));
7430 
7431 				switch(lvl) {
7432 				case 1:
7433 					pte = pmap_l1_to_l2(pde, pv->pv_va);
7434 					tpte = pmap_load(pte);
7435 					KASSERT((tpte & ATTR_DESCR_MASK) ==
7436 					    L2_BLOCK,
7437 					    ("Attempting to remove an invalid "
7438 					    "block: %lx", tpte));
7439 					break;
7440 				case 2:
7441 					pte = pmap_l2_to_l3(pde, pv->pv_va);
7442 					tpte = pmap_load(pte);
7443 					KASSERT((tpte & ATTR_DESCR_MASK) ==
7444 					    L3_PAGE,
7445 					    ("Attempting to remove an invalid "
7446 					     "page: %lx", tpte));
7447 					break;
7448 				default:
7449 					panic(
7450 					    "Invalid page directory level: %d",
7451 					    lvl);
7452 				}
7453 
7454 				/*
7455 				 * We cannot remove wired mappings at this time.
7456 				 *
7457 				 * For L3C superpages, all of the constituent PTEs
7458 				 * should have the wired bit set, so we don't
7459 				 * check for ATTR_CONTIGUOUS here.
7460 				 */
7461 				if (tpte & ATTR_SW_WIRED) {
7462 					allfree = 0;
7463 					continue;
7464 				}
7465 
7466 				/* Mark free */
7467 				pc->pc_map[field] |= bitmask;
7468 
7469 				/*
7470 				 * Because this pmap is not active on other
7471 				 * processors, the dirty bit cannot have
7472 				 * changed state since we last loaded pte.
7473 				 */
7474 				pmap_clear(pte);
7475 
7476 				pa = PTE_TO_PHYS(tpte);
7477 
7478 				m = PHYS_TO_VM_PAGE(pa);
7479 				KASSERT(m->phys_addr == pa,
7480 				    ("vm_page_t %p phys_addr mismatch %016jx %016jx",
7481 				    m, (uintmax_t)m->phys_addr,
7482 				    (uintmax_t)tpte));
7483 
7484 				KASSERT((m->flags & PG_FICTITIOUS) != 0 ||
7485 				    m < &vm_page_array[vm_page_array_size],
7486 				    ("pmap_remove_pages: bad pte %#jx",
7487 				    (uintmax_t)tpte));
7488 
7489 				/*
7490 				 * Update the vm_page_t clean/reference bits.
7491 				 *
7492 				 * We don't check for ATTR_CONTIGUOUS here
7493 				 * because writeable L3C superpages are expected
7494 				 * to be dirty, i.e., every constituent PTE
7495 				 * should be dirty.
7496 				 */
7497 				if (pmap_pte_dirty(pmap, tpte)) {
7498 					switch (lvl) {
7499 					case 1:
7500 						for (mt = m; mt < &m[L2_SIZE / PAGE_SIZE]; mt++)
7501 							vm_page_dirty(mt);
7502 						break;
7503 					case 2:
7504 						vm_page_dirty(m);
7505 						break;
7506 					}
7507 				}
7508 
7509 				CHANGE_PV_LIST_LOCK_TO_VM_PAGE(&lock, m);
7510 
7511 				switch (lvl) {
7512 				case 1:
7513 					pmap_resident_count_dec(pmap,
7514 					    L2_SIZE / PAGE_SIZE);
7515 					pvh = page_to_pvh(m);
7516 					TAILQ_REMOVE(&pvh->pv_list, pv,pv_next);
7517 					pvh->pv_gen++;
7518 					if (TAILQ_EMPTY(&pvh->pv_list)) {
7519 						for (mt = m; mt < &m[L2_SIZE / PAGE_SIZE]; mt++)
7520 							if ((mt->a.flags & PGA_WRITEABLE) != 0 &&
7521 							    TAILQ_EMPTY(&mt->md.pv_list))
7522 								vm_page_aflag_clear(mt, PGA_WRITEABLE);
7523 					}
7524 					ml3 = pmap_remove_pt_page(pmap,
7525 					    pv->pv_va);
7526 					if (ml3 != NULL) {
7527 						KASSERT(vm_page_any_valid(ml3),
7528 						    ("pmap_remove_pages: l3 page not promoted"));
7529 						pmap_resident_count_dec(pmap,1);
7530 						KASSERT(ml3->ref_count == NL3PG,
7531 						    ("pmap_remove_pages: l3 page ref count error"));
7532 						ml3->ref_count = 0;
7533 						pmap_add_delayed_free_list(ml3,
7534 						    &free, false);
7535 					}
7536 					break;
7537 				case 2:
7538 					pmap_resident_count_dec(pmap, 1);
7539 					TAILQ_REMOVE(&m->md.pv_list, pv,
7540 					    pv_next);
7541 					m->md.pv_gen++;
7542 					if ((m->a.flags & PGA_WRITEABLE) != 0 &&
7543 					    !pmap_page_is_mapped_locked(m))
7544 						vm_page_aflag_clear(m,
7545 						    PGA_WRITEABLE);
7546 					break;
7547 				}
7548 				pmap_unuse_pt(pmap, pv->pv_va, pmap_load(pde),
7549 				    &free);
7550 				freed++;
7551 			}
7552 		}
7553 		PV_STAT(atomic_add_long(&pv_entry_frees, freed));
7554 		PV_STAT(atomic_add_int(&pv_entry_spare, freed));
7555 		PV_STAT(atomic_subtract_long(&pv_entry_count, freed));
7556 		if (allfree) {
7557 			TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
7558 			TAILQ_INSERT_TAIL(&free_chunks[pc_to_domain(pc)], pc,
7559 			    pc_list);
7560 		}
7561 	}
7562 	if (lock != NULL)
7563 		rw_wunlock(lock);
7564 	pmap_invalidate_all(pmap);
7565 	pmap_bti_deassign_all(pmap);
7566 	free_pv_chunk_batch(free_chunks);
7567 	PMAP_UNLOCK(pmap);
7568 	vm_page_free_pages_toq(&free, true);
7569 }
7570 
7571 /*
7572  * This is used to check if a page has been accessed or modified.
7573  */
7574 static bool
7575 pmap_page_test_mappings(vm_page_t m, bool accessed, bool modified)
7576 {
7577 	struct rwlock *lock;
7578 	pv_entry_t pv;
7579 	struct md_page *pvh;
7580 	pt_entry_t l3e, mask, *pte, value;
7581 	pmap_t pmap;
7582 	int md_gen, pvh_gen;
7583 	bool rv;
7584 
7585 	rv = false;
7586 	lock = VM_PAGE_TO_PV_LIST_LOCK(m);
7587 	rw_rlock(lock);
7588 restart:
7589 	TAILQ_FOREACH(pv, &m->md.pv_list, pv_next) {
7590 		pmap = PV_PMAP(pv);
7591 		PMAP_ASSERT_STAGE1(pmap);
7592 		if (!PMAP_TRYLOCK(pmap)) {
7593 			md_gen = m->md.pv_gen;
7594 			rw_runlock(lock);
7595 			PMAP_LOCK(pmap);
7596 			rw_rlock(lock);
7597 			if (md_gen != m->md.pv_gen) {
7598 				PMAP_UNLOCK(pmap);
7599 				goto restart;
7600 			}
7601 		}
7602 		pte = pmap_pte_exists(pmap, pv->pv_va, 3, __func__);
7603 		mask = 0;
7604 		value = 0;
7605 		if (modified) {
7606 			mask |= ATTR_S1_AP_RW_BIT;
7607 			value |= ATTR_S1_AP(ATTR_S1_AP_RW);
7608 		}
7609 		if (accessed) {
7610 			mask |= ATTR_AF | ATTR_DESCR_MASK;
7611 			value |= ATTR_AF | L3_PAGE;
7612 		}
7613 		l3e = pmap_load(pte);
7614 		if ((l3e & ATTR_CONTIGUOUS) != 0)
7615 			l3e = pmap_load_l3c(pte);
7616 		PMAP_UNLOCK(pmap);
7617 		rv = (l3e & mask) == value;
7618 		if (rv)
7619 			goto out;
7620 	}
7621 	if ((m->flags & PG_FICTITIOUS) == 0) {
7622 		pvh = page_to_pvh(m);
7623 		TAILQ_FOREACH(pv, &pvh->pv_list, pv_next) {
7624 			pmap = PV_PMAP(pv);
7625 			PMAP_ASSERT_STAGE1(pmap);
7626 			if (!PMAP_TRYLOCK(pmap)) {
7627 				md_gen = m->md.pv_gen;
7628 				pvh_gen = pvh->pv_gen;
7629 				rw_runlock(lock);
7630 				PMAP_LOCK(pmap);
7631 				rw_rlock(lock);
7632 				if (md_gen != m->md.pv_gen ||
7633 				    pvh_gen != pvh->pv_gen) {
7634 					PMAP_UNLOCK(pmap);
7635 					goto restart;
7636 				}
7637 			}
7638 			pte = pmap_pte_exists(pmap, pv->pv_va, 2, __func__);
7639 			mask = 0;
7640 			value = 0;
7641 			if (modified) {
7642 				mask |= ATTR_S1_AP_RW_BIT;
7643 				value |= ATTR_S1_AP(ATTR_S1_AP_RW);
7644 			}
7645 			if (accessed) {
7646 				mask |= ATTR_AF | ATTR_DESCR_MASK;
7647 				value |= ATTR_AF | L2_BLOCK;
7648 			}
7649 			rv = (pmap_load(pte) & mask) == value;
7650 			PMAP_UNLOCK(pmap);
7651 			if (rv)
7652 				goto out;
7653 		}
7654 	}
7655 out:
7656 	rw_runlock(lock);
7657 	return (rv);
7658 }
7659 
7660 /*
7661  *	pmap_is_modified:
7662  *
7663  *	Return whether or not the specified physical page was modified
7664  *	in any physical maps.
7665  */
7666 bool
7667 pmap_is_modified(vm_page_t m)
7668 {
7669 
7670 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
7671 	    ("pmap_is_modified: page %p is not managed", m));
7672 
7673 	/*
7674 	 * If the page is not busied then this check is racy.
7675 	 */
7676 	if (!pmap_page_is_write_mapped(m))
7677 		return (false);
7678 	return (pmap_page_test_mappings(m, false, true));
7679 }
7680 
7681 /*
7682  *	pmap_is_prefaultable:
7683  *
7684  *	Return whether or not the specified virtual address is eligible
7685  *	for prefault.
7686  */
7687 bool
7688 pmap_is_prefaultable(pmap_t pmap, vm_offset_t addr)
7689 {
7690 	pd_entry_t *pde;
7691 	pt_entry_t *pte;
7692 	bool rv;
7693 	int lvl;
7694 
7695 	/*
7696 	 * Return true if and only if the L3 entry for the specified virtual
7697 	 * address is allocated but invalid.
7698 	 */
7699 	rv = false;
7700 	PMAP_LOCK(pmap);
7701 	pde = pmap_pde(pmap, addr, &lvl);
7702 	if (pde != NULL && lvl == 2) {
7703 		pte = pmap_l2_to_l3(pde, addr);
7704 		rv = pmap_load(pte) == 0;
7705 	}
7706 	PMAP_UNLOCK(pmap);
7707 	return (rv);
7708 }
7709 
7710 /*
7711  *	pmap_is_referenced:
7712  *
7713  *	Return whether or not the specified physical page was referenced
7714  *	in any physical maps.
7715  */
7716 bool
7717 pmap_is_referenced(vm_page_t m)
7718 {
7719 
7720 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
7721 	    ("pmap_is_referenced: page %p is not managed", m));
7722 	return (pmap_page_test_mappings(m, true, false));
7723 }
7724 
7725 /*
7726  * Clear the write and modified bits in each of the given page's mappings.
7727  */
7728 void
7729 pmap_remove_write(vm_page_t m)
7730 {
7731 	struct md_page *pvh;
7732 	pmap_t pmap;
7733 	struct rwlock *lock;
7734 	pv_entry_t next_pv, pv;
7735 	pt_entry_t oldpte, *pte, set, clear, mask, val;
7736 	vm_offset_t va;
7737 	int md_gen, pvh_gen;
7738 
7739 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
7740 	    ("pmap_remove_write: page %p is not managed", m));
7741 	vm_page_assert_busied(m);
7742 
7743 	if (!pmap_page_is_write_mapped(m))
7744 		return;
7745 	lock = VM_PAGE_TO_PV_LIST_LOCK(m);
7746 	pvh = (m->flags & PG_FICTITIOUS) != 0 ? &pv_dummy : page_to_pvh(m);
7747 	rw_wlock(lock);
7748 retry:
7749 	TAILQ_FOREACH_SAFE(pv, &pvh->pv_list, pv_next, next_pv) {
7750 		pmap = PV_PMAP(pv);
7751 		PMAP_ASSERT_STAGE1(pmap);
7752 		if (!PMAP_TRYLOCK(pmap)) {
7753 			pvh_gen = pvh->pv_gen;
7754 			rw_wunlock(lock);
7755 			PMAP_LOCK(pmap);
7756 			rw_wlock(lock);
7757 			if (pvh_gen != pvh->pv_gen) {
7758 				PMAP_UNLOCK(pmap);
7759 				goto retry;
7760 			}
7761 		}
7762 		va = pv->pv_va;
7763 		pte = pmap_pte_exists(pmap, va, 2, __func__);
7764 		if ((pmap_load(pte) & ATTR_SW_DBM) != 0)
7765 			(void)pmap_demote_l2_locked(pmap, pte, va, &lock);
7766 		KASSERT(lock == VM_PAGE_TO_PV_LIST_LOCK(m),
7767 		    ("inconsistent pv lock %p %p for page %p",
7768 		    lock, VM_PAGE_TO_PV_LIST_LOCK(m), m));
7769 		PMAP_UNLOCK(pmap);
7770 	}
7771 	TAILQ_FOREACH(pv, &m->md.pv_list, pv_next) {
7772 		pmap = PV_PMAP(pv);
7773 		if (!PMAP_TRYLOCK(pmap)) {
7774 			pvh_gen = pvh->pv_gen;
7775 			md_gen = m->md.pv_gen;
7776 			rw_wunlock(lock);
7777 			PMAP_LOCK(pmap);
7778 			rw_wlock(lock);
7779 			if (pvh_gen != pvh->pv_gen ||
7780 			    md_gen != m->md.pv_gen) {
7781 				PMAP_UNLOCK(pmap);
7782 				goto retry;
7783 			}
7784 		}
7785 		pte = pmap_pte_exists(pmap, pv->pv_va, 3, __func__);
7786 		oldpte = pmap_load(pte);
7787 		if ((oldpte & ATTR_SW_DBM) != 0) {
7788 			if ((oldpte & ATTR_CONTIGUOUS) != 0) {
7789 				(void)pmap_demote_l3c(pmap, pte, pv->pv_va);
7790 
7791 				/*
7792 				 * The L3 entry's accessed bit may have
7793 				 * changed.
7794 				 */
7795 				oldpte = pmap_load(pte);
7796 			}
7797 			if (pmap->pm_stage == PM_STAGE1) {
7798 				set = ATTR_S1_AP_RW_BIT;
7799 				clear = 0;
7800 				mask = ATTR_S1_AP_RW_BIT;
7801 				val = ATTR_S1_AP(ATTR_S1_AP_RW);
7802 			} else {
7803 				set = 0;
7804 				clear = ATTR_S2_S2AP(ATTR_S2_S2AP_WRITE);
7805 				mask = ATTR_S2_S2AP(ATTR_S2_S2AP_WRITE);
7806 				val = ATTR_S2_S2AP(ATTR_S2_S2AP_WRITE);
7807 			}
7808 			clear |= ATTR_SW_DBM;
7809 			while (!atomic_fcmpset_64(pte, &oldpte,
7810 			    (oldpte | set) & ~clear))
7811 				cpu_spinwait();
7812 
7813 			if ((oldpte & mask) == val)
7814 				vm_page_dirty(m);
7815 			pmap_invalidate_page(pmap, pv->pv_va, true);
7816 		}
7817 		PMAP_UNLOCK(pmap);
7818 	}
7819 	rw_wunlock(lock);
7820 	vm_page_aflag_clear(m, PGA_WRITEABLE);
7821 }
7822 
7823 /*
7824  *	pmap_ts_referenced:
7825  *
7826  *	Return a count of reference bits for a page, clearing those bits.
7827  *	It is not necessary for every reference bit to be cleared, but it
7828  *	is necessary that 0 only be returned when there are truly no
7829  *	reference bits set.
7830  *
7831  *	As an optimization, update the page's dirty field if a modified bit is
7832  *	found while counting reference bits.  This opportunistic update can be
7833  *	performed at low cost and can eliminate the need for some future calls
7834  *	to pmap_is_modified().  However, since this function stops after
7835  *	finding PMAP_TS_REFERENCED_MAX reference bits, it may not detect some
7836  *	dirty pages.  Those dirty pages will only be detected by a future call
7837  *	to pmap_is_modified().
7838  */
7839 int
7840 pmap_ts_referenced(vm_page_t m)
7841 {
7842 	struct md_page *pvh;
7843 	pv_entry_t pv, pvf;
7844 	pmap_t pmap;
7845 	struct rwlock *lock;
7846 	pt_entry_t *pte, tpte;
7847 	vm_offset_t va;
7848 	vm_paddr_t pa;
7849 	int cleared, md_gen, not_cleared, pvh_gen;
7850 	struct spglist free;
7851 
7852 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
7853 	    ("pmap_ts_referenced: page %p is not managed", m));
7854 	SLIST_INIT(&free);
7855 	cleared = 0;
7856 	pvh = (m->flags & PG_FICTITIOUS) != 0 ? &pv_dummy : page_to_pvh(m);
7857 	lock = VM_PAGE_TO_PV_LIST_LOCK(m);
7858 	rw_wlock(lock);
7859 retry:
7860 	not_cleared = 0;
7861 	if ((pvf = TAILQ_FIRST(&pvh->pv_list)) == NULL)
7862 		goto small_mappings;
7863 	pv = pvf;
7864 	do {
7865 		if (pvf == NULL)
7866 			pvf = pv;
7867 		pmap = PV_PMAP(pv);
7868 		if (!PMAP_TRYLOCK(pmap)) {
7869 			pvh_gen = pvh->pv_gen;
7870 			rw_wunlock(lock);
7871 			PMAP_LOCK(pmap);
7872 			rw_wlock(lock);
7873 			if (pvh_gen != pvh->pv_gen) {
7874 				PMAP_UNLOCK(pmap);
7875 				goto retry;
7876 			}
7877 		}
7878 		va = pv->pv_va;
7879 		pte = pmap_pte_exists(pmap, va, 2, __func__);
7880 		tpte = pmap_load(pte);
7881 		if (pmap_pte_dirty(pmap, tpte)) {
7882 			/*
7883 			 * Although "tpte" is mapping a 2MB page, because
7884 			 * this function is called at a 4KB page granularity,
7885 			 * we only update the 4KB page under test.
7886 			 */
7887 			vm_page_dirty(m);
7888 		}
7889 		if ((tpte & ATTR_AF) != 0) {
7890 			pa = VM_PAGE_TO_PHYS(m);
7891 
7892 			/*
7893 			 * Since this reference bit is shared by 512 4KB pages,
7894 			 * it should not be cleared every time it is tested.
7895 			 * Apply a simple "hash" function on the physical page
7896 			 * number, the virtual superpage number, and the pmap
7897 			 * address to select one 4KB page out of the 512 on
7898 			 * which testing the reference bit will result in
7899 			 * clearing that reference bit.  This function is
7900 			 * designed to avoid the selection of the same 4KB page
7901 			 * for every 2MB page mapping.
7902 			 *
7903 			 * On demotion, a mapping that hasn't been referenced
7904 			 * is simply destroyed.  To avoid the possibility of a
7905 			 * subsequent page fault on a demoted wired mapping,
7906 			 * always leave its reference bit set.  Moreover,
7907 			 * since the superpage is wired, the current state of
7908 			 * its reference bit won't affect page replacement.
7909 			 */
7910 			if ((((pa >> PAGE_SHIFT) ^ (va >> L2_SHIFT) ^
7911 			    (uintptr_t)pmap) & (Ln_ENTRIES - 1)) == 0 &&
7912 			    (tpte & ATTR_SW_WIRED) == 0) {
7913 				pmap_clear_bits(pte, ATTR_AF);
7914 				pmap_invalidate_page(pmap, va, true);
7915 				cleared++;
7916 			} else
7917 				not_cleared++;
7918 		}
7919 		PMAP_UNLOCK(pmap);
7920 		/* Rotate the PV list if it has more than one entry. */
7921 		if (TAILQ_NEXT(pv, pv_next) != NULL) {
7922 			TAILQ_REMOVE(&pvh->pv_list, pv, pv_next);
7923 			TAILQ_INSERT_TAIL(&pvh->pv_list, pv, pv_next);
7924 			pvh->pv_gen++;
7925 		}
7926 		if (cleared + not_cleared >= PMAP_TS_REFERENCED_MAX)
7927 			goto out;
7928 	} while ((pv = TAILQ_FIRST(&pvh->pv_list)) != pvf);
7929 small_mappings:
7930 	if ((pvf = TAILQ_FIRST(&m->md.pv_list)) == NULL)
7931 		goto out;
7932 	pv = pvf;
7933 	do {
7934 		if (pvf == NULL)
7935 			pvf = pv;
7936 		pmap = PV_PMAP(pv);
7937 		if (!PMAP_TRYLOCK(pmap)) {
7938 			pvh_gen = pvh->pv_gen;
7939 			md_gen = m->md.pv_gen;
7940 			rw_wunlock(lock);
7941 			PMAP_LOCK(pmap);
7942 			rw_wlock(lock);
7943 			if (pvh_gen != pvh->pv_gen || md_gen != m->md.pv_gen) {
7944 				PMAP_UNLOCK(pmap);
7945 				goto retry;
7946 			}
7947 		}
7948 		pte = pmap_pte_exists(pmap, pv->pv_va, 3, __func__);
7949 		tpte = pmap_load(pte);
7950 		if (pmap_pte_dirty(pmap, tpte))
7951 			vm_page_dirty(m);
7952 		if ((tpte & ATTR_AF) != 0) {
7953 			if ((tpte & ATTR_SW_WIRED) == 0) {
7954 				/*
7955 				 * Clear the accessed bit in this L3 entry
7956 				 * regardless of the contiguous bit.
7957 				 */
7958 				pmap_clear_bits(pte, ATTR_AF);
7959 				pmap_invalidate_page(pmap, pv->pv_va, true);
7960 				cleared++;
7961 			} else
7962 				not_cleared++;
7963 		} else if ((tpte & ATTR_CONTIGUOUS) != 0 &&
7964 		    (pmap_load_l3c(pte) & ATTR_AF) != 0) {
7965 			/*
7966 			 * An L3C superpage mapping is regarded as accessed
7967 			 * until the accessed bit has been cleared in all
7968 			 * of its constituent entries.
7969 			 */
7970 			not_cleared++;
7971 		}
7972 		PMAP_UNLOCK(pmap);
7973 		/* Rotate the PV list if it has more than one entry. */
7974 		if (TAILQ_NEXT(pv, pv_next) != NULL) {
7975 			TAILQ_REMOVE(&m->md.pv_list, pv, pv_next);
7976 			TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_next);
7977 			m->md.pv_gen++;
7978 		}
7979 	} while ((pv = TAILQ_FIRST(&m->md.pv_list)) != pvf && cleared +
7980 	    not_cleared < PMAP_TS_REFERENCED_MAX);
7981 out:
7982 	rw_wunlock(lock);
7983 	vm_page_free_pages_toq(&free, true);
7984 	return (cleared + not_cleared);
7985 }
7986 
7987 /*
7988  *	Apply the given advice to the specified range of addresses within the
7989  *	given pmap.  Depending on the advice, clear the referenced and/or
7990  *	modified flags in each mapping and set the mapped page's dirty field.
7991  */
7992 void
7993 pmap_advise(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, int advice)
7994 {
7995 	struct rwlock *lock;
7996 	vm_offset_t va, va_next, dva;
7997 	vm_page_t m;
7998 	pd_entry_t *l0, *l1, *l2, oldl2;
7999 	pt_entry_t *l3, *dl3, oldl3;
8000 
8001 	PMAP_ASSERT_STAGE1(pmap);
8002 
8003 	if (advice != MADV_DONTNEED && advice != MADV_FREE)
8004 		return;
8005 
8006 	PMAP_LOCK(pmap);
8007 	for (; sva < eva; sva = va_next) {
8008 		l0 = pmap_l0(pmap, sva);
8009 		if (pmap_load(l0) == 0) {
8010 			va_next = (sva + L0_SIZE) & ~L0_OFFSET;
8011 			if (va_next < sva)
8012 				va_next = eva;
8013 			continue;
8014 		}
8015 
8016 		va_next = (sva + L1_SIZE) & ~L1_OFFSET;
8017 		if (va_next < sva)
8018 			va_next = eva;
8019 		l1 = pmap_l0_to_l1(l0, sva);
8020 		if (pmap_load(l1) == 0)
8021 			continue;
8022 		if ((pmap_load(l1) & ATTR_DESCR_MASK) == L1_BLOCK) {
8023 			PMAP_ASSERT_L1_BLOCKS_SUPPORTED;
8024 			continue;
8025 		}
8026 
8027 		va_next = (sva + L2_SIZE) & ~L2_OFFSET;
8028 		if (va_next < sva)
8029 			va_next = eva;
8030 		l2 = pmap_l1_to_l2(l1, sva);
8031 		oldl2 = pmap_load(l2);
8032 		if (oldl2 == 0)
8033 			continue;
8034 		if ((oldl2 & ATTR_DESCR_MASK) == L2_BLOCK) {
8035 			if ((oldl2 & ATTR_SW_MANAGED) == 0)
8036 				continue;
8037 			lock = NULL;
8038 			if (!pmap_demote_l2_locked(pmap, l2, sva, &lock)) {
8039 				if (lock != NULL)
8040 					rw_wunlock(lock);
8041 
8042 				/*
8043 				 * The 2MB page mapping was destroyed.
8044 				 */
8045 				continue;
8046 			}
8047 
8048 			/*
8049 			 * Unless the page mappings are wired, remove the
8050 			 * mapping to a single page so that a subsequent
8051 			 * access may repromote.  Choosing the last page
8052 			 * within the address range [sva, min(va_next, eva))
8053 			 * generally results in more repromotions.  Since the
8054 			 * underlying page table page is fully populated, this
8055 			 * removal never frees a page table page.
8056 			 */
8057 			if ((oldl2 & ATTR_SW_WIRED) == 0) {
8058 				va = eva;
8059 				if (va > va_next)
8060 					va = va_next;
8061 				va -= PAGE_SIZE;
8062 				KASSERT(va >= sva,
8063 				    ("pmap_advise: no address gap"));
8064 				l3 = pmap_l2_to_l3(l2, va);
8065 				KASSERT(pmap_load(l3) != 0,
8066 				    ("pmap_advise: invalid PTE"));
8067 				pmap_remove_l3(pmap, l3, va, pmap_load(l2),
8068 				    NULL, &lock);
8069 			}
8070 			if (lock != NULL)
8071 				rw_wunlock(lock);
8072 		}
8073 		KASSERT((pmap_load(l2) & ATTR_DESCR_MASK) == L2_TABLE,
8074 		    ("pmap_advise: invalid L2 entry after demotion"));
8075 		if (va_next > eva)
8076 			va_next = eva;
8077 		va = va_next;
8078 		for (l3 = pmap_l2_to_l3(l2, sva); sva != va_next; l3++,
8079 		    sva += L3_SIZE) {
8080 			oldl3 = pmap_load(l3);
8081 			if ((oldl3 & (ATTR_SW_MANAGED | ATTR_DESCR_MASK)) !=
8082 			    (ATTR_SW_MANAGED | L3_PAGE))
8083 				goto maybe_invlrng;
8084 			else if (pmap_pte_dirty(pmap, oldl3)) {
8085 				if (advice == MADV_DONTNEED) {
8086 					/*
8087 					 * Future calls to pmap_is_modified()
8088 					 * can be avoided by making the page
8089 					 * dirty now.
8090 					 */
8091 					m = PTE_TO_VM_PAGE(oldl3);
8092 					vm_page_dirty(m);
8093 				}
8094 				if ((oldl3 & ATTR_CONTIGUOUS) != 0) {
8095 					/*
8096 					 * Unconditionally demote the L3C
8097 					 * superpage because we do not allow
8098 					 * writeable, clean superpages.
8099 					 */
8100 					(void)pmap_demote_l3c(pmap, l3, sva);
8101 
8102 					/*
8103                                          * Destroy the final mapping before the
8104                                          * next L3C boundary or va_next,
8105 					 * whichever comes first, so that a
8106 					 * subsequent access may act as a
8107 					 * repromotion trigger.
8108 					 */
8109                                         if ((oldl3 & ATTR_SW_WIRED) == 0) {
8110 						dva = MIN((sva & ~L3C_OFFSET) +
8111 						    L3C_SIZE - PAGE_SIZE,
8112 						    va_next - PAGE_SIZE);
8113 						dl3 = pmap_l2_to_l3(l2, dva);
8114 						KASSERT(pmap_load(dl3) != 0,
8115 						    ("pmap_advise: invalid PTE"));
8116 						lock = NULL;
8117 						pmap_remove_l3(pmap, dl3, dva,
8118 						    pmap_load(l2), NULL, &lock);
8119 						if (lock != NULL)
8120 							rw_wunlock(lock);
8121 					}
8122 
8123 					/*
8124 					 * The L3 entry's accessed bit may have
8125 					 * changed.
8126 					 */
8127 					oldl3 = pmap_load(l3);
8128 				}
8129 
8130 				/*
8131 				 * Check that we did not just destroy this entry so
8132 				 * we avoid corrupting the page able.
8133 				 */
8134 				if (oldl3 != 0) {
8135 					while (!atomic_fcmpset_long(l3, &oldl3,
8136 					    (oldl3 & ~ATTR_AF) |
8137 					    ATTR_S1_AP(ATTR_S1_AP_RO)))
8138 						cpu_spinwait();
8139 				}
8140 			} else if ((oldl3 & ATTR_AF) != 0) {
8141 				/*
8142 				 * Clear the accessed bit in this L3 entry
8143 				 * regardless of the contiguous bit.
8144 				 */
8145 				pmap_clear_bits(l3, ATTR_AF);
8146 			} else
8147 				goto maybe_invlrng;
8148 			if (va == va_next)
8149 				va = sva;
8150 			continue;
8151 maybe_invlrng:
8152 			if (va != va_next) {
8153 				pmap_s1_invalidate_range(pmap, va, sva, true);
8154 				va = va_next;
8155 			}
8156 		}
8157 		if (va != va_next)
8158 			pmap_s1_invalidate_range(pmap, va, sva, true);
8159 	}
8160 	PMAP_UNLOCK(pmap);
8161 }
8162 
8163 /*
8164  *	Clear the modify bits on the specified physical page.
8165  */
8166 void
8167 pmap_clear_modify(vm_page_t m)
8168 {
8169 	struct md_page *pvh;
8170 	struct rwlock *lock;
8171 	pmap_t pmap;
8172 	pv_entry_t next_pv, pv;
8173 	pd_entry_t *l2, oldl2;
8174 	pt_entry_t *l3, oldl3;
8175 	vm_offset_t va;
8176 	int md_gen, pvh_gen;
8177 
8178 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
8179 	    ("pmap_clear_modify: page %p is not managed", m));
8180 	vm_page_assert_busied(m);
8181 
8182 	if (!pmap_page_is_write_mapped(m))
8183 		return;
8184 	pvh = (m->flags & PG_FICTITIOUS) != 0 ? &pv_dummy : page_to_pvh(m);
8185 	lock = VM_PAGE_TO_PV_LIST_LOCK(m);
8186 	rw_wlock(lock);
8187 restart:
8188 	TAILQ_FOREACH_SAFE(pv, &pvh->pv_list, pv_next, next_pv) {
8189 		pmap = PV_PMAP(pv);
8190 		PMAP_ASSERT_STAGE1(pmap);
8191 		if (!PMAP_TRYLOCK(pmap)) {
8192 			pvh_gen = pvh->pv_gen;
8193 			rw_wunlock(lock);
8194 			PMAP_LOCK(pmap);
8195 			rw_wlock(lock);
8196 			if (pvh_gen != pvh->pv_gen) {
8197 				PMAP_UNLOCK(pmap);
8198 				goto restart;
8199 			}
8200 		}
8201 		va = pv->pv_va;
8202 		l2 = pmap_l2(pmap, va);
8203 		oldl2 = pmap_load(l2);
8204 		/* If oldl2 has ATTR_SW_DBM set, then it is also dirty. */
8205 		if ((oldl2 & ATTR_SW_DBM) != 0 &&
8206 		    pmap_demote_l2_locked(pmap, l2, va, &lock) &&
8207 		    (oldl2 & ATTR_SW_WIRED) == 0) {
8208 			/*
8209 			 * Write protect the mapping to a single page so that
8210 			 * a subsequent write access may repromote.
8211 			 */
8212 			va += VM_PAGE_TO_PHYS(m) - PTE_TO_PHYS(oldl2);
8213 			l3 = pmap_l2_to_l3(l2, va);
8214 			oldl3 = pmap_load(l3);
8215 			while (!atomic_fcmpset_long(l3, &oldl3,
8216 			    (oldl3 & ~ATTR_SW_DBM) | ATTR_S1_AP(ATTR_S1_AP_RO)))
8217 				cpu_spinwait();
8218 			vm_page_dirty(m);
8219 			pmap_s1_invalidate_page(pmap, va, true);
8220 		}
8221 		PMAP_UNLOCK(pmap);
8222 	}
8223 	TAILQ_FOREACH(pv, &m->md.pv_list, pv_next) {
8224 		pmap = PV_PMAP(pv);
8225 		PMAP_ASSERT_STAGE1(pmap);
8226 		if (!PMAP_TRYLOCK(pmap)) {
8227 			md_gen = m->md.pv_gen;
8228 			pvh_gen = pvh->pv_gen;
8229 			rw_wunlock(lock);
8230 			PMAP_LOCK(pmap);
8231 			rw_wlock(lock);
8232 			if (pvh_gen != pvh->pv_gen || md_gen != m->md.pv_gen) {
8233 				PMAP_UNLOCK(pmap);
8234 				goto restart;
8235 			}
8236 		}
8237 		l2 = pmap_l2(pmap, pv->pv_va);
8238 		l3 = pmap_l2_to_l3(l2, pv->pv_va);
8239 		oldl3 = pmap_load(l3);
8240 		KASSERT((oldl3 & ATTR_CONTIGUOUS) == 0 ||
8241 		    (oldl3 & (ATTR_SW_DBM | ATTR_S1_AP_RW_BIT)) !=
8242 		    (ATTR_SW_DBM | ATTR_S1_AP(ATTR_S1_AP_RO)),
8243 		    ("writeable L3C superpage not dirty"));
8244 		if ((oldl3 & (ATTR_S1_AP_RW_BIT | ATTR_SW_DBM)) == ATTR_SW_DBM) {
8245 			if ((oldl3 & ATTR_CONTIGUOUS) != 0)
8246 				(void)pmap_demote_l3c(pmap, l3, pv->pv_va);
8247 			pmap_set_bits(l3, ATTR_S1_AP(ATTR_S1_AP_RO));
8248 			pmap_s1_invalidate_page(pmap, pv->pv_va, true);
8249 		}
8250 		PMAP_UNLOCK(pmap);
8251 	}
8252 	rw_wunlock(lock);
8253 }
8254 
8255 void *
8256 pmap_mapbios(vm_paddr_t pa, vm_size_t size)
8257 {
8258 	struct pmap_preinit_mapping *ppim;
8259 	vm_offset_t va, offset;
8260 	pd_entry_t old_l2e, *pde;
8261 	pt_entry_t *l2;
8262 	int i, lvl, l2_blocks, free_l2_count, start_idx;
8263 
8264 	/* Use the DMAP region if we can */
8265 	if (PHYS_IN_DMAP(pa) && PHYS_IN_DMAP(pa + size - 1) &&
8266 	    pmap_kmapped_range(PHYS_TO_DMAP(pa), size))
8267 		return (PHYS_TO_DMAP(pa));
8268 
8269 	if (!vm_initialized) {
8270 		/*
8271 		 * No L3 ptables so map entire L2 blocks where start VA is:
8272 		 * 	preinit_map_va + start_idx * L2_SIZE
8273 		 * There may be duplicate mappings (multiple VA -> same PA) but
8274 		 * ARM64 dcache is always PIPT so that's acceptable.
8275 		 */
8276 		 if (size == 0)
8277 			 return (NULL);
8278 
8279 		 /* Calculate how many L2 blocks are needed for the mapping */
8280 		l2_blocks = (roundup2(pa + size, L2_SIZE) -
8281 		    rounddown2(pa, L2_SIZE)) >> L2_SHIFT;
8282 
8283 		offset = pa & L2_OFFSET;
8284 
8285 		if (preinit_map_va == 0)
8286 			return (NULL);
8287 
8288 		/* Map 2MiB L2 blocks from reserved VA space */
8289 
8290 		free_l2_count = 0;
8291 		start_idx = -1;
8292 		/* Find enough free contiguous VA space */
8293 		for (i = 0; i < PMAP_PREINIT_MAPPING_COUNT; i++) {
8294 			ppim = pmap_preinit_mapping + i;
8295 			if (free_l2_count > 0 && ppim->pa != 0) {
8296 				/* Not enough space here */
8297 				free_l2_count = 0;
8298 				start_idx = -1;
8299 				continue;
8300 			}
8301 
8302 			if (ppim->pa == 0) {
8303 				/* Free L2 block */
8304 				if (start_idx == -1)
8305 					start_idx = i;
8306 				free_l2_count++;
8307 				if (free_l2_count == l2_blocks)
8308 					break;
8309 			}
8310 		}
8311 		if (free_l2_count != l2_blocks)
8312 			panic("%s: too many preinit mappings", __func__);
8313 
8314 		va = preinit_map_va + (start_idx * L2_SIZE);
8315 		for (i = start_idx; i < start_idx + l2_blocks; i++) {
8316 			/* Mark entries as allocated */
8317 			ppim = pmap_preinit_mapping + i;
8318 			ppim->pa = pa;
8319 			ppim->va = (char *)va + offset;
8320 			ppim->size = size;
8321 		}
8322 
8323 		/* Map L2 blocks */
8324 		pa = rounddown2(pa, L2_SIZE);
8325 		old_l2e = 0;
8326 		for (i = 0; i < l2_blocks; i++) {
8327 			pde = pmap_pde(kernel_pmap, va, &lvl);
8328 			KASSERT(pde != NULL,
8329 			    ("pmap_mapbios: Invalid page entry, va: 0x%lx",
8330 			    va));
8331 			KASSERT(lvl == 1,
8332 			    ("pmap_mapbios: Invalid level %d", lvl));
8333 
8334 			/* Insert L2_BLOCK */
8335 			l2 = pmap_l1_to_l2(pde, va);
8336 			old_l2e |= pmap_load_store(l2,
8337 			    PHYS_TO_PTE(pa) | ATTR_AF | pmap_sh_attr |
8338 			    ATTR_S1_XN | ATTR_KERN_GP |
8339 			    ATTR_S1_IDX(VM_MEMATTR_WRITE_BACK) | L2_BLOCK);
8340 
8341 			va += L2_SIZE;
8342 			pa += L2_SIZE;
8343 		}
8344 		if ((old_l2e & ATTR_DESCR_VALID) != 0)
8345 			pmap_s1_invalidate_all_kernel();
8346 		else {
8347 			/*
8348 			 * Because the old entries were invalid and the new
8349 			 * mappings are not executable, an isb is not required.
8350 			 */
8351 			dsb(ishst);
8352 		}
8353 
8354 		va = preinit_map_va + (start_idx * L2_SIZE);
8355 
8356 	} else {
8357 		/* kva_alloc may be used to map the pages */
8358 		offset = pa & PAGE_MASK;
8359 		size = round_page(offset + size);
8360 
8361 		va = (vm_offset_t)kva_alloc(size);
8362 		if (va == 0)
8363 			panic("%s: Couldn't allocate KVA", __func__);
8364 
8365 		pde = pmap_pde(kernel_pmap, va, &lvl);
8366 		KASSERT(lvl == 2, ("pmap_mapbios: Invalid level %d", lvl));
8367 
8368 		/* L3 table is linked */
8369 		va = trunc_page(va);
8370 		pa = trunc_page(pa);
8371 		pmap_kenter(va, size, pa, memory_mapping_mode(pa));
8372 	}
8373 
8374 	return ((void *)(va + offset));
8375 }
8376 
8377 void
8378 pmap_unmapbios(void *p, vm_size_t size)
8379 {
8380 	struct pmap_preinit_mapping *ppim;
8381 	char *va;
8382 	vm_offset_t offset, va_trunc;
8383 	pd_entry_t *pde;
8384 	pt_entry_t *l2;
8385 	int error __diagused, i, lvl, l2_blocks, block;
8386 	bool preinit_map;
8387 
8388 	va = p;
8389 	if (VIRT_IN_DMAP(va)) {
8390 		KASSERT(VIRT_IN_DMAP(va + size - 1),
8391 		    ("%s: End address not in DMAP region: %p", __func__,
8392 		    va + size - 1));
8393 		/* Ensure the attributes are as expected for the DMAP region */
8394 		PMAP_LOCK(kernel_pmap);
8395 		error = pmap_change_props_locked(va, size,
8396 		    PROT_READ | PROT_WRITE, VM_MEMATTR_DEFAULT, -1, false);
8397 		PMAP_UNLOCK(kernel_pmap);
8398 		KASSERT(error == 0, ("%s: Failed to reset DMAP attributes: %d",
8399 		    __func__, error));
8400 
8401 		return;
8402 	}
8403 
8404 	l2_blocks =
8405 	   (roundup2(va + size, L2_SIZE) - rounddown2(va, L2_SIZE)) >> L2_SHIFT;
8406 	KASSERT(l2_blocks > 0, ("pmap_unmapbios: invalid size %lx", size));
8407 
8408 	/* Remove preinit mapping */
8409 	preinit_map = false;
8410 	block = 0;
8411 	for (i = 0; i < PMAP_PREINIT_MAPPING_COUNT; i++) {
8412 		ppim = pmap_preinit_mapping + i;
8413 		if (ppim->va == va) {
8414 			KASSERT(ppim->size == size,
8415 			    ("pmap_unmapbios: size mismatch"));
8416 			ppim->va = NULL;
8417 			ppim->pa = 0;
8418 			ppim->size = 0;
8419 			preinit_map = true;
8420 			offset = block * L2_SIZE;
8421 			va_trunc = rounddown2((vm_offset_t)va, L2_SIZE) +
8422 			    offset;
8423 
8424 			/* Remove L2_BLOCK */
8425 			pde = pmap_pde(kernel_pmap, va_trunc, &lvl);
8426 			KASSERT(pde != NULL,
8427 			    ("pmap_unmapbios: Invalid page entry, va: 0x%lx",
8428 			    va_trunc));
8429 			l2 = pmap_l1_to_l2(pde, va_trunc);
8430 			pmap_clear(l2);
8431 
8432 			if (block == (l2_blocks - 1))
8433 				break;
8434 			block++;
8435 		}
8436 	}
8437 	if (preinit_map) {
8438 		pmap_s1_invalidate_all_kernel();
8439 		return;
8440 	}
8441 
8442 	/* Unmap the pages reserved with kva_alloc. */
8443 	if (vm_initialized) {
8444 		offset = (vm_offset_t)va & PAGE_MASK;
8445 		size = round_page(offset + size);
8446 		va = trunc_page(va);
8447 
8448 		/* Unmap and invalidate the pages */
8449 		pmap_kremove_device((vm_offset_t)va, size);
8450 
8451 		kva_free(va, size);
8452 	}
8453 }
8454 
8455 /*
8456  * Sets the memory attribute for the specified page.
8457  */
8458 void
8459 pmap_page_set_memattr(vm_page_t m, vm_memattr_t ma)
8460 {
8461 	if (m->md.pv_memattr == ma)
8462 		return;
8463 
8464 	m->md.pv_memattr = ma;
8465 
8466 	/*
8467 	 * If "m" is a normal page, update its direct mapping.  This update
8468 	 * can be relied upon to perform any cache operations that are
8469 	 * required for data coherence.
8470 	 */
8471 	if ((m->flags & PG_FICTITIOUS) == 0 &&
8472 	    pmap_change_attr(VM_PAGE_TO_DMAP(m), PAGE_SIZE,
8473 	    m->md.pv_memattr) != 0)
8474 		panic("memory attribute change on the direct map failed");
8475 }
8476 
8477 /*
8478  * Changes the specified virtual address range's memory type to that given by
8479  * the parameter "mode".  The specified virtual address range must be
8480  * completely contained within either the direct map or the kernel map.  If
8481  * the virtual address range is contained within the kernel map, then the
8482  * memory type for each of the corresponding ranges of the direct map is also
8483  * changed.  (The corresponding ranges of the direct map are those ranges that
8484  * map the same physical pages as the specified virtual address range.)  These
8485  * changes to the direct map are necessary because Intel describes the
8486  * behavior of their processors as "undefined" if two or more mappings to the
8487  * same physical page have different memory types.
8488  *
8489  * Returns zero if the change completed successfully, and either EINVAL or
8490  * ENOMEM if the change failed.  Specifically, EINVAL is returned if some part
8491  * of the virtual address range was not mapped, and ENOMEM is returned if
8492  * there was insufficient memory available to complete the change.  In the
8493  * latter case, the memory type may have been changed on some part of the
8494  * virtual address range or the direct map.
8495  */
8496 int
8497 pmap_change_attr(void *va, vm_size_t size, int mode)
8498 {
8499 	int error;
8500 
8501 	PMAP_LOCK(kernel_pmap);
8502 	error = pmap_change_props_locked(va, size, PROT_NONE, mode, -1, false);
8503 	PMAP_UNLOCK(kernel_pmap);
8504 	return (error);
8505 }
8506 
8507 int
8508 pmap_change_dmap_attr(int mode)
8509 {
8510 	int error;
8511 
8512 	KASSERT(mode == VM_MEMATTR_WRITE_BACK ||
8513 	    mode == VM_MEMATTR_TAGGED,
8514 	    ("%s: mode %d must be compatible with write-back", __func__, mode));
8515 
8516 	PMAP_LOCK(kernel_pmap);
8517 	error = pmap_change_props_locked((void *)DMAP_MIN_ADDRESS,
8518 	    dmap_max_addr - DMAP_MIN_ADDRESS, PROT_NONE, mode, dmap_attr, true);
8519 	if (error == 0)
8520 		dmap_attr = mode;
8521 	PMAP_UNLOCK(kernel_pmap);
8522 	return (error);
8523 }
8524 
8525 /*
8526  * Changes the specified virtual address range's protections to those
8527  * specified by "prot".  Like pmap_change_attr(), protections for aliases
8528  * in the direct map are updated as well.  Protections on aliasing mappings may
8529  * be a subset of the requested protections; for example, mappings in the direct
8530  * map are never executable.
8531  */
8532 int
8533 pmap_change_prot(void *va, vm_size_t size, vm_prot_t prot)
8534 {
8535 	int error;
8536 
8537 	/* Only supported within the kernel map. */
8538 	if ((vm_offset_t)va < VM_MIN_KERNEL_ADDRESS)
8539 		return (EINVAL);
8540 
8541 	PMAP_LOCK(kernel_pmap);
8542 	error = pmap_change_props_locked(va, size, prot, -1, -1, false);
8543 	PMAP_UNLOCK(kernel_pmap);
8544 	return (error);
8545 }
8546 
8547 static int
8548 pmap_change_props_locked(void *addr, vm_size_t size, vm_prot_t prot,
8549     int mode, int old_mode, bool skip_unmapped)
8550 {
8551 	vm_offset_t base, offset, tmpva, va;
8552 	vm_size_t pte_size;
8553 	vm_paddr_t pa;
8554 	pt_entry_t pte, *ptep, *newpte;
8555 	pt_entry_t bits, mask, old_mode_bits, old_mode_mask;
8556 	char *tmpptep;
8557 	int lvl, rv;
8558 
8559 	PMAP_LOCK_ASSERT(kernel_pmap, MA_OWNED);
8560 	va = (vm_offset_t)addr;
8561 	base = trunc_page(va);
8562 	offset = va & PAGE_MASK;
8563 	size = round_page(offset + size);
8564 
8565 	if (!VIRT_IN_DMAP(base) &&
8566 	    !(base >= VM_MIN_KERNEL_ADDRESS && base < VM_MAX_KERNEL_ADDRESS))
8567 		return (EINVAL);
8568 
8569 	bits = old_mode_bits = 0;
8570 	mask = old_mode_mask = 0;
8571 	if (mode != -1) {
8572 		bits = ATTR_S1_IDX(mode);
8573 		mask = ATTR_S1_IDX_MASK;
8574 		if (mode == VM_MEMATTR_DEVICE) {
8575 			mask |= ATTR_S1_XN;
8576 			bits |= ATTR_S1_XN;
8577 		}
8578 	}
8579 	if (old_mode != -1) {
8580 		old_mode_bits = ATTR_S1_IDX(old_mode);
8581 		old_mode_mask = ATTR_S1_IDX_MASK;
8582 	}
8583 	if (prot != VM_PROT_NONE) {
8584 		/* Don't mark the DMAP as executable. It never is on arm64. */
8585 		if (VIRT_IN_DMAP(base)) {
8586 			prot &= ~VM_PROT_EXECUTE;
8587 			/*
8588 			 * XXX Mark the DMAP as writable for now. We rely
8589 			 * on this in ddb & dtrace to insert breakpoint
8590 			 * instructions.
8591 			 */
8592 			prot |= VM_PROT_WRITE;
8593 		}
8594 
8595 		if ((prot & VM_PROT_WRITE) == 0) {
8596 			bits |= ATTR_S1_AP(ATTR_S1_AP_RO);
8597 		}
8598 		if ((prot & VM_PROT_EXECUTE) == 0) {
8599 			bits |= ATTR_S1_PXN;
8600 		}
8601 		bits |= ATTR_S1_UXN;
8602 		mask |= ATTR_S1_AP_MASK | ATTR_S1_XN;
8603 	}
8604 
8605 	for (tmpva = base; tmpva < base + size; ) {
8606 		ptep = pmap_pte(kernel_pmap, tmpva, &lvl);
8607 		if (ptep == NULL && !skip_unmapped) {
8608 			return (EINVAL);
8609 		} else if ((ptep == NULL && skip_unmapped) ||
8610 		    (pmap_load(ptep) & mask) == bits ||
8611 		    (pmap_load(ptep) & old_mode_mask) != old_mode_bits) {
8612 			/*
8613 			 * We already have one of the following meaning
8614 			 * we can skip this memory region::
8615 			 *  - No memory mapped at this address
8616 			 *  - The new attributes are already set
8617 			 *  - The expected attributes are incorrect
8618 			 */
8619 			switch (lvl) {
8620 			default:
8621 				panic("Invalid DMAP table level: %d\n", lvl);
8622 			case 1:
8623 				tmpva = (tmpva & ~L1_OFFSET) + L1_SIZE;
8624 				break;
8625 			case 2:
8626 				tmpva = (tmpva & ~L2_OFFSET) + L2_SIZE;
8627 				break;
8628 			case 3:
8629 				tmpva += PAGE_SIZE;
8630 				break;
8631 			}
8632 		} else {
8633 			/* We can't demote/promote this entry */
8634 			MPASS((pmap_load(ptep) & ATTR_SW_NO_PROMOTE) == 0);
8635 
8636 			/*
8637 			 * Find the entry and demote it if the requested change
8638 			 * only applies to part of the address range mapped by
8639 			 * the entry.
8640 			 */
8641 			switch (lvl) {
8642 			default:
8643 				panic("Invalid DMAP table level: %d\n", lvl);
8644 			case 1:
8645 				PMAP_ASSERT_L1_BLOCKS_SUPPORTED;
8646 				if ((tmpva & L1_OFFSET) == 0 &&
8647 				    (base + size - tmpva) >= L1_SIZE) {
8648 					pte_size = L1_SIZE;
8649 					break;
8650 				}
8651 				newpte = pmap_demote_l1(kernel_pmap, ptep,
8652 				    tmpva & ~L1_OFFSET);
8653 				if (newpte == NULL)
8654 					return (EINVAL);
8655 				ptep = pmap_l1_to_l2(ptep, tmpva);
8656 				/* FALLTHROUGH */
8657 			case 2:
8658 				if ((pmap_load(ptep) & ATTR_CONTIGUOUS) != 0) {
8659 					if ((tmpva & L2C_OFFSET) == 0 &&
8660 					    (base + size - tmpva) >= L2C_SIZE) {
8661 						pte_size = L2C_SIZE;
8662 						break;
8663 					}
8664 					if (!pmap_demote_l2c(kernel_pmap, ptep,
8665 					    tmpva))
8666 						return (EINVAL);
8667 				}
8668 				if ((tmpva & L2_OFFSET) == 0 &&
8669 				    (base + size - tmpva) >= L2_SIZE) {
8670 					pte_size = L2_SIZE;
8671 					break;
8672 				}
8673 				newpte = pmap_demote_l2(kernel_pmap, ptep,
8674 				    tmpva);
8675 				if (newpte == NULL)
8676 					return (EINVAL);
8677 				ptep = pmap_l2_to_l3(ptep, tmpva);
8678 				/* FALLTHROUGH */
8679 			case 3:
8680 				if ((pmap_load(ptep) & ATTR_CONTIGUOUS) != 0) {
8681 					if ((tmpva & L3C_OFFSET) == 0 &&
8682 					    (base + size - tmpva) >= L3C_SIZE) {
8683 						pte_size = L3C_SIZE;
8684 						break;
8685 					}
8686 					if (!pmap_demote_l3c(kernel_pmap, ptep,
8687 					    tmpva))
8688 						return (EINVAL);
8689 				}
8690 				pte_size = PAGE_SIZE;
8691 				break;
8692 			}
8693 
8694 			tmpptep = 0;
8695 			if (tmpva <= (vm_offset_t)ptep &&
8696 			    tmpva + pte_size > (vm_offset_t)ptep) {
8697 				vm_paddr_t pte_pa;
8698 
8699 				mtx_lock(&cmap_lock);
8700 				tmpptep = cmap1_addr;
8701 				pte_pa = DMAP_TO_PHYS((vm_offset_t)ptep);
8702 				pmap_store(cmap1_pte, ATTR_AF |
8703 				    pmap_sh_attr | ATTR_S1_AP(ATTR_S1_AP_RW) |
8704 				    ATTR_S1_XN | ATTR_KERN_GP |
8705 				    ATTR_S1_IDX(VM_MEMATTR_WRITE_BACK) |
8706 				    PHYS_TO_PTE(pte_pa &~L3_OFFSET) | L3_PAGE);
8707 				dsb(ishst);
8708 				ptep = (pt_entry_t *)(tmpptep +
8709 				    ((vm_offset_t)ptep & PAGE_MASK));
8710 			}
8711 
8712 			/* Update the entry */
8713 			pte = pmap_load(ptep);
8714 			pte &= ~mask;
8715 			pte |= bits;
8716 
8717 			switch (pte_size) {
8718 			case L2C_SIZE:
8719 				pmap_update_strided(kernel_pmap, ptep, ptep +
8720 				    L2C_ENTRIES, pte, tmpva, L2_SIZE, L2C_SIZE);
8721 				break;
8722 			case L3C_SIZE:
8723 				pmap_update_strided(kernel_pmap, ptep, ptep +
8724 				    L3C_ENTRIES, pte, tmpva, L3_SIZE, L3C_SIZE);
8725 				break;
8726 			default:
8727 				/*
8728 				 * We are updating a single block or page entry,
8729 				 * so regardless of pte_size pass PAGE_SIZE in
8730 				 * order that a single TLB invalidation is
8731 				 * performed.
8732 				 */
8733 				pmap_update_entry(kernel_pmap, ptep, pte, tmpva,
8734 				    PAGE_SIZE, true);
8735 				break;
8736 			}
8737 
8738 			if (tmpptep != 0) {
8739 				pmap_clear(cmap1_pte);
8740 				pmap_s1_invalidate_page(kernel_pmap,
8741 				    (vm_offset_t)tmpptep, true);
8742 				mtx_unlock(&cmap_lock);
8743 			}
8744 
8745 			pa = PTE_TO_PHYS(pte);
8746 			if (!VIRT_IN_DMAP(tmpva) && PHYS_IN_DMAP(pa)) {
8747 				int dmap_mode;
8748 
8749 				/*
8750 				 * When booting on HW with MTE enabled we may
8751 				 * need to swap to a tagged type for the DMAP
8752 				 * to allow tags to be set through it.
8753 				 */
8754 				if (mode == VM_MEMATTR_WRITE_BACK)
8755 					dmap_mode = dmap_attr;
8756 				else
8757 					dmap_mode = mode;
8758 
8759 				/*
8760 				 * Keep the DMAP memory in sync.
8761 				 */
8762 				rv = pmap_change_props_locked(
8763 				    PHYS_TO_DMAP(pa), pte_size,
8764 				    prot, dmap_mode, old_mode, true);
8765 				if (rv != 0)
8766 					return (rv);
8767 			}
8768 
8769 			/*
8770 			 * If moving to a non-cacheable entry flush
8771 			 * the cache.
8772 			 */
8773 			if (mode == VM_MEMATTR_UNCACHEABLE)
8774 				cpu_dcache_wbinv_range((void *)tmpva, pte_size);
8775 			tmpva += pte_size;
8776 		}
8777 	}
8778 
8779 	return (0);
8780 }
8781 
8782 /*
8783  * Create an L2 table to map all addresses within an L1 mapping.
8784  */
8785 static pt_entry_t *
8786 pmap_demote_l1(pmap_t pmap, pt_entry_t *l1, vm_offset_t va)
8787 {
8788 	pt_entry_t *l2, newl2, oldl1;
8789 	char *tmpl1;
8790 	vm_paddr_t l2phys, phys;
8791 	vm_page_t ml2;
8792 	int i;
8793 
8794 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
8795 	oldl1 = pmap_load(l1);
8796 	PMAP_ASSERT_L1_BLOCKS_SUPPORTED;
8797 	KASSERT((oldl1 & ATTR_DESCR_MASK) == L1_BLOCK,
8798 	    ("pmap_demote_l1: Demoting a non-block entry"));
8799 	KASSERT((va & L1_OFFSET) == 0,
8800 	    ("pmap_demote_l1: Invalid virtual address %#lx", va));
8801 	KASSERT((oldl1 & ATTR_SW_MANAGED) == 0,
8802 	    ("pmap_demote_l1: Level 1 table shouldn't be managed"));
8803 	KASSERT((oldl1 & ATTR_SW_NO_PROMOTE) == 0,
8804 	    ("pmap_demote_l1: Demoting entry with no-demote flag set"));
8805 
8806 	tmpl1 = NULL;
8807 	if (va <= (vm_offset_t)l1 && va + L1_SIZE > (vm_offset_t)l1) {
8808 		tmpl1 = kva_alloc(PAGE_SIZE);
8809 		if (tmpl1 == NULL)
8810 			return (NULL);
8811 	}
8812 
8813 	if ((ml2 = vm_page_alloc_noobj(VM_ALLOC_INTERRUPT | VM_ALLOC_WIRED)) ==
8814 	    NULL) {
8815 		CTR2(KTR_PMAP, "pmap_demote_l1: failure for va %#lx"
8816 		    " in pmap %p", va, pmap);
8817 		l2 = NULL;
8818 		goto fail;
8819 	}
8820 
8821 	l2phys = VM_PAGE_TO_PHYS(ml2);
8822 	l2 = PHYS_TO_DMAP(l2phys);
8823 
8824 	/* Address the range points at */
8825 	phys = PTE_TO_PHYS(oldl1);
8826 	/* The attributed from the old l1 table to be copied */
8827 	newl2 = oldl1 & ATTR_MASK;
8828 
8829 	/* Create the new entries */
8830 	newl2 |= ATTR_CONTIGUOUS;
8831 	for (i = 0; i < Ln_ENTRIES; i++) {
8832 		l2[i] = newl2 | phys;
8833 		phys += L2_SIZE;
8834 	}
8835 	KASSERT(l2[0] == (ATTR_CONTIGUOUS | (oldl1 & ~ATTR_DESCR_MASK) |
8836 	    L2_BLOCK), ("Invalid l2 page (%lx != %lx)", l2[0],
8837 	    ATTR_CONTIGUOUS | (oldl1 & ~ATTR_DESCR_MASK) | L2_BLOCK));
8838 
8839 	if (tmpl1 != NULL) {
8840 		pmap_kenter((vm_offset_t)tmpl1, PAGE_SIZE,
8841 		    DMAP_TO_PHYS(l1) & ~L3_OFFSET,
8842 		    VM_MEMATTR_WRITE_BACK);
8843 		l1 = (pt_entry_t *)(tmpl1 + ((vm_offset_t)l1 & PAGE_MASK));
8844 	}
8845 
8846 	pmap_update_entry(pmap, l1, l2phys | L1_TABLE, va, PAGE_SIZE, true);
8847 
8848 	counter_u64_add(pmap_l1_demotions, 1);
8849 fail:
8850 	if (tmpl1 != NULL) {
8851 		pmap_kremove((vm_offset_t)tmpl1);
8852 		kva_free(tmpl1, PAGE_SIZE);
8853 	}
8854 
8855 	return (l2);
8856 }
8857 
8858 static void
8859 pmap_fill_l3(pt_entry_t *firstl3, pt_entry_t newl3)
8860 {
8861 	pt_entry_t *l3;
8862 
8863 	for (l3 = firstl3; l3 - firstl3 < Ln_ENTRIES; l3++) {
8864 		*l3 = newl3;
8865 		newl3 += L3_SIZE;
8866 	}
8867 }
8868 
8869 static void
8870 pmap_demote_l2_check(pt_entry_t *firstl3p __unused, pt_entry_t newl3e __unused)
8871 {
8872 #ifdef INVARIANTS
8873 #ifdef DIAGNOSTIC
8874 	pt_entry_t *xl3p, *yl3p;
8875 
8876 	for (xl3p = firstl3p; xl3p < firstl3p + Ln_ENTRIES;
8877 	    xl3p++, newl3e += PAGE_SIZE) {
8878 		if (PTE_TO_PHYS(pmap_load(xl3p)) != PTE_TO_PHYS(newl3e)) {
8879 			printf("pmap_demote_l2: xl3e %zd and newl3e map "
8880 			    "different pages: found %#lx, expected %#lx\n",
8881 			    xl3p - firstl3p, pmap_load(xl3p), newl3e);
8882 			printf("page table dump\n");
8883 			for (yl3p = firstl3p; yl3p < firstl3p + Ln_ENTRIES;
8884 			    yl3p++) {
8885 				printf("%zd %#lx\n", yl3p - firstl3p,
8886 				    pmap_load(yl3p));
8887 			}
8888 			panic("firstpte");
8889 		}
8890 	}
8891 #else
8892 	KASSERT(PTE_TO_PHYS(pmap_load(firstl3p)) == PTE_TO_PHYS(newl3e),
8893 	    ("pmap_demote_l2: firstl3 and newl3e map different physical"
8894 	    " addresses"));
8895 #endif
8896 #endif
8897 }
8898 
8899 static void
8900 pmap_demote_l2_abort(pmap_t pmap, vm_offset_t va, pt_entry_t *l2,
8901     struct rwlock **lockp)
8902 {
8903 	struct spglist free;
8904 
8905 	SLIST_INIT(&free);
8906 	(void)pmap_remove_l2(pmap, l2, va, pmap_load(pmap_l1(pmap, va)), true,
8907 	    &free, lockp);
8908 	vm_page_free_pages_toq(&free, true);
8909 }
8910 
8911 /*
8912  * Create an L3 table to map all addresses within an L2 mapping.
8913  */
8914 static pt_entry_t *
8915 pmap_demote_l2_locked(pmap_t pmap, pt_entry_t *l2, vm_offset_t va,
8916     struct rwlock **lockp)
8917 {
8918 	pt_entry_t *l3, newl3, oldl2;
8919 	char *tmpl2;
8920 	vm_paddr_t l3phys;
8921 	vm_page_t ml3;
8922 
8923 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
8924 	PMAP_ASSERT_STAGE1(pmap);
8925 	KASSERT(ADDR_IS_CANONICAL(va),
8926 	    ("%s: Address not in canonical form: %lx", __func__, va));
8927 
8928 	l3 = NULL;
8929 	oldl2 = pmap_load(l2);
8930 	KASSERT((oldl2 & ATTR_DESCR_MASK) == L2_BLOCK,
8931 	    ("pmap_demote_l2: Demoting a non-block entry"));
8932 	KASSERT((oldl2 & ATTR_SW_NO_PROMOTE) == 0,
8933 	    ("pmap_demote_l2: Demoting entry with no-demote flag set"));
8934 	va &= ~L2_OFFSET;
8935 
8936 	tmpl2 = NULL;
8937 	if (va <= (vm_offset_t)l2 && va + L2_SIZE > (vm_offset_t)l2) {
8938 		tmpl2 = kva_alloc(PAGE_SIZE);
8939 		if (tmpl2 == NULL)
8940 			return (NULL);
8941 	}
8942 
8943 	/*
8944 	 * Invalidate the 2MB page mapping and return "failure" if the
8945 	 * mapping was never accessed and not wired.
8946 	 */
8947 	if ((oldl2 & ATTR_AF) == 0) {
8948 		if ((oldl2 & ATTR_SW_WIRED) == 0) {
8949 			pmap_demote_l2_abort(pmap, va, l2, lockp);
8950 			CTR2(KTR_PMAP,
8951 			    "pmap_demote_l2: failure for va %#lx in pmap %p",
8952 			    va, pmap);
8953 			goto fail;
8954 		}
8955 		ml3 = pmap_remove_pt_page(pmap, va);
8956 		/* Fill the PTP with L3Es that have ATTR_AF cleared. */
8957 		ml3->valid = 0;
8958 	} else if ((ml3 = pmap_remove_pt_page(pmap, va)) == NULL) {
8959 		KASSERT((oldl2 & ATTR_SW_WIRED) == 0,
8960 		    ("pmap_demote_l2: page table page for a wired mapping"
8961 		    " is missing"));
8962 
8963 		/*
8964 		 * If the page table page is missing and the mapping
8965 		 * is for a kernel address, the mapping must belong to
8966 		 * either the direct map or the early kernel memory.
8967 		 * Page table pages are preallocated for every other
8968 		 * part of the kernel address space, so the direct map
8969 		 * region and early kernel memory are the only parts of the
8970 		 * kernel address space that must be handled here.
8971 		 */
8972 		KASSERT(ADDR_IS_USER(va) || VIRT_IN_DMAP(va) ||
8973 		    (va >= VM_MIN_KERNEL_ADDRESS && va < kernel_vm_end),
8974 		    ("pmap_demote_l2: No saved mpte for va %#lx", va));
8975 
8976 		/*
8977 		 * If the 2MB page mapping belongs to the direct map
8978 		 * region of the kernel's address space, then the page
8979 		 * allocation request specifies the highest possible
8980 		 * priority (VM_ALLOC_INTERRUPT).  Otherwise, the
8981 		 * priority is normal.
8982 		 */
8983 		ml3 = vm_page_alloc_noobj(
8984 		    (VIRT_IN_DMAP(va) ? VM_ALLOC_INTERRUPT : 0) |
8985 		    VM_ALLOC_WIRED);
8986 
8987 		/*
8988 		 * If the allocation of the new page table page fails,
8989 		 * invalidate the 2MB page mapping and return "failure".
8990 		 */
8991 		if (ml3 == NULL) {
8992 			pmap_demote_l2_abort(pmap, va, l2, lockp);
8993 			CTR2(KTR_PMAP, "pmap_demote_l2: failure for va %#lx"
8994 			    " in pmap %p", va, pmap);
8995 			goto fail;
8996 		}
8997 		ml3->pindex = pmap_l2_pindex(va);
8998 
8999 		if (ADDR_IS_USER(va)) {
9000 			ml3->ref_count = NL3PG;
9001 			pmap_resident_count_inc(pmap, 1);
9002 		}
9003 	}
9004 	l3phys = VM_PAGE_TO_PHYS(ml3);
9005 	l3 = PHYS_TO_DMAP(l3phys);
9006 	newl3 = ATTR_CONTIGUOUS | (oldl2 & ~ATTR_DESCR_MASK) | L3_PAGE;
9007 	KASSERT((oldl2 & (ATTR_S1_AP_RW_BIT | ATTR_SW_DBM)) !=
9008 	    (ATTR_S1_AP(ATTR_S1_AP_RO) | ATTR_SW_DBM),
9009 	    ("pmap_demote_l2: L2 entry is writeable but not dirty"));
9010 
9011 	/*
9012 	 * If the PTP is not leftover from an earlier promotion or it does not
9013 	 * have ATTR_AF set in every L3E, then fill it.  The new L3Es will all
9014 	 * have ATTR_AF set, unless this is a wired mapping with ATTR_AF clear.
9015 	 *
9016 	 * When pmap_update_entry() clears the old L2 mapping, it (indirectly)
9017 	 * performs a dsb().  That dsb() ensures that the stores for filling
9018 	 * "l3" are visible before "l3" is added to the page table.
9019 	 */
9020 	if (!vm_page_all_valid(ml3))
9021 		pmap_fill_l3(l3, newl3);
9022 
9023 	pmap_demote_l2_check(l3, newl3);
9024 
9025 	/*
9026 	 * If the mapping has changed attributes, update the L3Es.
9027 	 */
9028 	if ((pmap_load(l3) & ATTR_PROMOTE) != (newl3 & ATTR_PROMOTE))
9029 		pmap_fill_l3(l3, newl3);
9030 
9031 	/*
9032 	 * Map the temporary page so we don't lose access to the l2 table.
9033 	 */
9034 	if (tmpl2 != NULL) {
9035 		pmap_kenter((vm_offset_t)tmpl2, PAGE_SIZE,
9036 		    DMAP_TO_PHYS(l2) & ~L3_OFFSET,
9037 		    VM_MEMATTR_WRITE_BACK);
9038 		l2 = (pt_entry_t *)(tmpl2 + ((vm_offset_t)l2 & PAGE_MASK));
9039 	}
9040 
9041 	/*
9042 	 * The spare PV entries must be reserved prior to demoting the
9043 	 * mapping, that is, prior to changing the PDE.  Otherwise, the state
9044 	 * of the L2 and the PV lists will be inconsistent, which can result
9045 	 * in reclaim_pv_chunk() attempting to remove a PV entry from the
9046 	 * wrong PV list and pmap_pv_demote_l2() failing to find the expected
9047 	 * PV entry for the 2MB page mapping that is being demoted.
9048 	 */
9049 	if ((oldl2 & ATTR_SW_MANAGED) != 0)
9050 		reserve_pv_entries(pmap, Ln_ENTRIES - 1, lockp);
9051 
9052 	/*
9053 	 * Pass PAGE_SIZE so that a single TLB invalidation is performed on
9054 	 * the 2MB page mapping.
9055 	 */
9056 	pmap_update_entry(pmap, l2, l3phys | L2_TABLE, va, PAGE_SIZE, true);
9057 
9058 	/*
9059 	 * Demote the PV entry.
9060 	 */
9061 	if ((oldl2 & ATTR_SW_MANAGED) != 0)
9062 		pmap_pv_demote_l2(pmap, va, PTE_TO_PHYS(oldl2), lockp);
9063 
9064 	counter_u64_add(pmap_l2_demotions, 1);
9065 	CTR3(KTR_PMAP, "pmap_demote_l2: success for va %#lx"
9066 	    " in pmap %p %lx", va, pmap, l3[0]);
9067 
9068 fail:
9069 	if (tmpl2 != NULL) {
9070 		pmap_kremove((vm_offset_t)tmpl2);
9071 		kva_free(tmpl2, PAGE_SIZE);
9072 	}
9073 
9074 	return (l3);
9075 
9076 }
9077 
9078 static pt_entry_t *
9079 pmap_demote_l2(pmap_t pmap, pt_entry_t *l2, vm_offset_t va)
9080 {
9081 	struct rwlock *lock;
9082 	pt_entry_t *l3;
9083 
9084 	lock = NULL;
9085 	l3 = pmap_demote_l2_locked(pmap, l2, va, &lock);
9086 	if (lock != NULL)
9087 		rw_wunlock(lock);
9088 	return (l3);
9089 }
9090 
9091 /*
9092  * Demote an L2C superpage mapping to L2C_ENTRIES L2 block mappings.
9093  */
9094 static bool
9095 pmap_demote_l2c(pmap_t pmap, pt_entry_t *l2p, vm_offset_t va)
9096 {
9097 	pd_entry_t *l2c_end, *l2c_start, l2e, mask, nbits, *tl2p;
9098 	char *tmpl3;
9099 	register_t intr;
9100 
9101 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
9102 	PMAP_ASSERT_STAGE1(pmap);
9103 	l2c_start = (pd_entry_t *)((uintptr_t)l2p & ~((L2C_ENTRIES *
9104 	    sizeof(pd_entry_t)) - 1));
9105 	l2c_end = l2c_start + L2C_ENTRIES;
9106 	tmpl3 = NULL;
9107 	if ((va & ~L2C_OFFSET) < (vm_offset_t)l2c_end &&
9108 	    (vm_offset_t)l2c_start < (va & ~L2C_OFFSET) + L2C_SIZE) {
9109 		tmpl3 = kva_alloc(PAGE_SIZE);
9110 		if (tmpl3 == NULL)
9111 			return (false);
9112 		pmap_kenter((vm_offset_t)tmpl3, PAGE_SIZE,
9113 		    DMAP_TO_PHYS(l2c_start) & ~L3_OFFSET,
9114 		    VM_MEMATTR_WRITE_BACK);
9115 		l2c_start = (pd_entry_t *)(tmpl3 +
9116 		    ((vm_offset_t)l2c_start & PAGE_MASK));
9117 		l2c_end = (pd_entry_t *)(tmpl3 +
9118 		    ((vm_offset_t)l2c_end & PAGE_MASK));
9119 	}
9120 	mask = 0;
9121 	nbits = ATTR_DESCR_VALID;
9122 	intr = intr_disable();
9123 
9124 	/*
9125 	 * Break the mappings.
9126 	 */
9127 	for (tl2p = l2c_start; tl2p < l2c_end; tl2p++) {
9128 		/*
9129 		 * Clear the mapping's contiguous and valid bits, but leave
9130 		 * the rest of the entry unchanged, so that a lockless,
9131 		 * concurrent pmap_kextract() can still lookup the physical
9132 		 * address.
9133 		 */
9134 		l2e = pmap_load(tl2p);
9135 		KASSERT((l2e & ATTR_CONTIGUOUS) != 0,
9136 		    ("pmap_demote_l2c: missing ATTR_CONTIGUOUS"));
9137 		KASSERT((l2e & (ATTR_SW_DBM | ATTR_S1_AP_RW_BIT)) !=
9138 		    (ATTR_SW_DBM | ATTR_S1_AP(ATTR_S1_AP_RO)),
9139 		    ("pmap_demote_l2c: missing ATTR_S1_AP_RW"));
9140 		while (!atomic_fcmpset_64(tl2p, &l2e, l2e & ~(ATTR_CONTIGUOUS |
9141 		    ATTR_DESCR_VALID)))
9142 			cpu_spinwait();
9143 
9144 		/*
9145 		 * Hardware accessed and dirty bit maintenance might only
9146 		 * update a single L2 entry, so we must combine the accessed
9147 		 * and dirty bits from this entire set of contiguous L2
9148 		 * entries.
9149 		 */
9150 		if ((l2e & (ATTR_S1_AP_RW_BIT | ATTR_SW_DBM)) ==
9151 		    (ATTR_S1_AP(ATTR_S1_AP_RW) | ATTR_SW_DBM))
9152 			mask = ATTR_S1_AP_RW_BIT;
9153 		nbits |= l2e & ATTR_AF;
9154 	}
9155 	if ((nbits & ATTR_AF) != 0) {
9156 		pmap_s1_invalidate_strided(pmap, va & ~L2C_OFFSET, (va +
9157 		    L2C_SIZE) & ~L2C_OFFSET, L2_SIZE, true);
9158 	}
9159 
9160 	/*
9161 	 * Remake the mappings, updating the accessed and dirty bits.
9162 	 */
9163 	l2e = (pmap_load(l2c_start) & ~mask) | nbits;
9164 	for (tl2p = l2c_start; tl2p < l2c_end; tl2p++) {
9165 		pmap_store(tl2p, l2e);
9166 		l2e += L2_SIZE;
9167 	}
9168 	dsb(ishst);
9169 
9170 	intr_restore(intr);
9171 	if (tmpl3 != NULL) {
9172 		pmap_kremove((vm_offset_t)tmpl3);
9173 		kva_free(tmpl3, PAGE_SIZE);
9174 	}
9175 	counter_u64_add(pmap_l2c_demotions, 1);
9176 	CTR2(KTR_PMAP, "pmap_demote_l2c: success for va %#lx in pmap %p",
9177 	    va, pmap);
9178 	return (true);
9179 }
9180 
9181 /*
9182  * Demote a L3C superpage mapping to L3C_ENTRIES 4KB page mappings.
9183  */
9184 static bool
9185 pmap_demote_l3c(pmap_t pmap, pt_entry_t *l3p, vm_offset_t va)
9186 {
9187 	pt_entry_t *l3c_end, *l3c_start, l3e, mask, nbits, *tl3p;
9188 	char *tmpl3;
9189 	register_t intr;
9190 
9191 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
9192 	l3c_start = (pt_entry_t *)((uintptr_t)l3p & ~((L3C_ENTRIES *
9193 	    sizeof(pt_entry_t)) - 1));
9194 	l3c_end = l3c_start + L3C_ENTRIES;
9195 	tmpl3 = NULL;
9196 	if ((va & ~L3C_OFFSET) < (vm_offset_t)l3c_end &&
9197 	    (vm_offset_t)l3c_start < (va & ~L3C_OFFSET) + L3C_SIZE) {
9198 		tmpl3 = kva_alloc(PAGE_SIZE);
9199 		if (tmpl3 == NULL)
9200 			return (false);
9201 		pmap_kenter((vm_offset_t)tmpl3, PAGE_SIZE,
9202 		    DMAP_TO_PHYS(l3c_start) & ~L3_OFFSET,
9203 		    VM_MEMATTR_WRITE_BACK);
9204 		l3c_start = (pt_entry_t *)(tmpl3 +
9205 		    ((vm_offset_t)l3c_start & PAGE_MASK));
9206 		l3c_end = (pt_entry_t *)(tmpl3 +
9207 		    ((vm_offset_t)l3c_end & PAGE_MASK));
9208 	}
9209 	mask = 0;
9210 	nbits = ATTR_DESCR_VALID;
9211 	intr = intr_disable();
9212 
9213 	/*
9214 	 * Break the mappings.
9215 	 */
9216 	for (tl3p = l3c_start; tl3p < l3c_end; tl3p++) {
9217 		/*
9218 		 * Clear the mapping's contiguous and valid bits, but leave
9219 		 * the rest of the entry unchanged, so that a lockless,
9220 		 * concurrent pmap_kextract() can still lookup the physical
9221 		 * address.
9222 		 */
9223 		l3e = pmap_load(tl3p);
9224 		KASSERT((l3e & ATTR_CONTIGUOUS) != 0,
9225 		    ("pmap_demote_l3c: missing ATTR_CONTIGUOUS"));
9226 		KASSERT((l3e & (ATTR_SW_DBM | ATTR_S1_AP_RW_BIT)) !=
9227 		    (ATTR_SW_DBM | ATTR_S1_AP(ATTR_S1_AP_RO)),
9228 		    ("pmap_demote_l3c: missing ATTR_S1_AP_RW"));
9229 		while (!atomic_fcmpset_64(tl3p, &l3e, l3e & ~(ATTR_CONTIGUOUS |
9230 		    ATTR_DESCR_VALID)))
9231 			cpu_spinwait();
9232 
9233 		/*
9234 		 * Hardware accessed and dirty bit maintenance might only
9235 		 * update a single L3 entry, so we must combine the accessed
9236 		 * and dirty bits from this entire set of contiguous L3
9237 		 * entries.
9238 		 */
9239 		if ((l3e & (ATTR_S1_AP_RW_BIT | ATTR_SW_DBM)) ==
9240 		    (ATTR_S1_AP(ATTR_S1_AP_RW) | ATTR_SW_DBM))
9241 			mask = ATTR_S1_AP_RW_BIT;
9242 		nbits |= l3e & ATTR_AF;
9243 	}
9244 	if ((nbits & ATTR_AF) != 0) {
9245 		pmap_invalidate_range(pmap, va & ~L3C_OFFSET, (va + L3C_SIZE) &
9246 		    ~L3C_OFFSET, true);
9247 	}
9248 
9249 	/*
9250 	 * Remake the mappings, updating the accessed and dirty bits.
9251 	 */
9252 	l3e = (pmap_load(l3c_start) & ~mask) | nbits;
9253 	for (tl3p = l3c_start; tl3p < l3c_end; tl3p++) {
9254 		pmap_store(tl3p, l3e);
9255 		l3e += L3_SIZE;
9256 	}
9257 	dsb(ishst);
9258 
9259 	intr_restore(intr);
9260 	if (tmpl3 != NULL) {
9261 		pmap_kremove((vm_offset_t)tmpl3);
9262 		kva_free(tmpl3, PAGE_SIZE);
9263 	}
9264 	counter_u64_add(pmap_l3c_demotions, 1);
9265 	CTR2(KTR_PMAP, "pmap_demote_l3c: success for va %#lx in pmap %p",
9266 	    va, pmap);
9267 	return (true);
9268 }
9269 
9270 /*
9271  * Accumulate the accessed and dirty bits within a L3C superpage and
9272  * return the specified PTE with them applied correctly.
9273  */
9274 static pt_entry_t
9275 pmap_load_l3c(pt_entry_t *l3p)
9276 {
9277 	pt_entry_t *l3c_end, *l3c_start, l3e, mask, nbits, *tl3p;
9278 
9279 	l3c_start = (pt_entry_t *)((uintptr_t)l3p & ~((L3C_ENTRIES *
9280 	    sizeof(pt_entry_t)) - 1));
9281 	l3c_end = l3c_start + L3C_ENTRIES;
9282 	mask = 0;
9283 	nbits = 0;
9284 	/* Iterate over each mapping in the superpage. */
9285 	for (tl3p = l3c_start; tl3p < l3c_end; tl3p++) {
9286 		l3e = pmap_load(tl3p);
9287 		KASSERT((l3e & ATTR_CONTIGUOUS) != 0,
9288 		    ("pmap_load_l3c: missing ATTR_CONTIGUOUS"));
9289 		/* Update mask if the current page has its dirty bit set. */
9290 		if ((l3e & (ATTR_S1_AP_RW_BIT | ATTR_SW_DBM)) ==
9291 		    (ATTR_S1_AP(ATTR_S1_AP_RW) | ATTR_SW_DBM))
9292 			mask = ATTR_S1_AP_RW_BIT;
9293 		/* Update nbits if the accessed bit is set. */
9294 		nbits |= l3e & ATTR_AF;
9295 	}
9296 	return ((pmap_load(l3p) & ~mask) | nbits);
9297 }
9298 
9299 /*
9300  * Perform the pmap work for mincore(2).  If the page is not both referenced and
9301  * modified by this pmap, returns its physical address so that the caller can
9302  * find other mappings.
9303  */
9304 int
9305 pmap_mincore(pmap_t pmap, vm_offset_t addr, vm_paddr_t *pap)
9306 {
9307 	pt_entry_t *pte, tpte;
9308 	vm_paddr_t mask, pa;
9309 	int lvl, psind, val;
9310 	bool managed;
9311 
9312 	PMAP_ASSERT_STAGE1(pmap);
9313 	PMAP_LOCK(pmap);
9314 	pte = pmap_pte(pmap, addr, &lvl);
9315 	if (pte != NULL) {
9316 		tpte = pmap_load(pte);
9317 
9318 		switch (lvl) {
9319 		case 3:
9320 			mask = L3_OFFSET;
9321 			psind = (tpte & ATTR_CONTIGUOUS) != 0 ? 1 : 0;
9322 			break;
9323 		case 2:
9324 			mask = L2_OFFSET;
9325 			psind = 2;
9326 			break;
9327 		case 1:
9328 			mask = L1_OFFSET;
9329 			psind = 3;
9330 			break;
9331 		default:
9332 			panic("pmap_mincore: invalid level %d", lvl);
9333 		}
9334 
9335 		managed = (tpte & ATTR_SW_MANAGED) != 0;
9336 		val = MINCORE_INCORE | MINCORE_PSIND(psind);
9337 		if ((managed && pmap_pte_dirty(pmap, tpte)) || (!managed &&
9338 		    (tpte & ATTR_S1_AP_RW_BIT) == ATTR_S1_AP(ATTR_S1_AP_RW)))
9339 			val |= MINCORE_MODIFIED | MINCORE_MODIFIED_OTHER;
9340 		if ((tpte & ATTR_AF) == ATTR_AF)
9341 			val |= MINCORE_REFERENCED | MINCORE_REFERENCED_OTHER;
9342 
9343 		pa = PTE_TO_PHYS(tpte) | (addr & mask);
9344 	} else {
9345 		managed = false;
9346 		val = 0;
9347 	}
9348 
9349 	if ((val & (MINCORE_MODIFIED_OTHER | MINCORE_REFERENCED_OTHER)) !=
9350 	    (MINCORE_MODIFIED_OTHER | MINCORE_REFERENCED_OTHER) && managed) {
9351 		*pap = pa;
9352 	}
9353 	PMAP_UNLOCK(pmap);
9354 	return (val);
9355 }
9356 
9357 /*
9358  * Garbage collect every ASID that is neither active on a processor nor
9359  * reserved.
9360  */
9361 static void
9362 pmap_reset_asid_set(pmap_t pmap)
9363 {
9364 	pmap_t curpmap;
9365 	int asid, cpuid, epoch;
9366 	struct asid_set *set;
9367 	enum pmap_stage stage;
9368 
9369 	set = pmap->pm_asid_set;
9370 	stage = pmap->pm_stage;
9371 
9372 	set = pmap->pm_asid_set;
9373 	KASSERT(set != NULL, ("%s: NULL asid set", __func__));
9374 	mtx_assert(&set->asid_set_mutex, MA_OWNED);
9375 
9376 	/*
9377 	 * Ensure that the store to asid_epoch is globally visible before the
9378 	 * loads from pc_curpmap are performed.
9379 	 */
9380 	epoch = set->asid_epoch + 1;
9381 	if (epoch == INT_MAX)
9382 		epoch = 0;
9383 	set->asid_epoch = epoch;
9384 	dsb(ishst);
9385 	if (stage == PM_STAGE1) {
9386 		__asm __volatile("tlbi vmalle1is");
9387 	} else {
9388 		KASSERT(pmap_clean_stage2_tlbi != NULL,
9389 		    ("%s: Unset stage 2 tlb invalidation callback\n",
9390 		    __func__));
9391 		pmap_clean_stage2_tlbi();
9392 	}
9393 	dsb(ish);
9394 	bit_nclear(set->asid_set, ASID_FIRST_AVAILABLE,
9395 	    set->asid_set_size - 1);
9396 	CPU_FOREACH(cpuid) {
9397 		if (cpuid == curcpu)
9398 			continue;
9399 		if (stage == PM_STAGE1) {
9400 			curpmap = pcpu_find(cpuid)->pc_curpmap;
9401 			PMAP_ASSERT_STAGE1(pmap);
9402 		} else {
9403 			curpmap = pcpu_find(cpuid)->pc_curvmpmap;
9404 			if (curpmap == NULL)
9405 				continue;
9406 			PMAP_ASSERT_STAGE2(pmap);
9407 		}
9408 		KASSERT(curpmap->pm_asid_set == set, ("Incorrect set"));
9409 		asid = COOKIE_TO_ASID(curpmap->pm_cookie);
9410 		if (asid == -1)
9411 			continue;
9412 		bit_set(set->asid_set, asid);
9413 		curpmap->pm_cookie = COOKIE_FROM(asid, epoch);
9414 	}
9415 }
9416 
9417 /*
9418  * Allocate a new ASID for the specified pmap.
9419  */
9420 static void
9421 pmap_alloc_asid(pmap_t pmap)
9422 {
9423 	struct asid_set *set;
9424 	int new_asid;
9425 
9426 	set = pmap->pm_asid_set;
9427 	KASSERT(set != NULL, ("%s: NULL asid set", __func__));
9428 
9429 	mtx_lock_spin(&set->asid_set_mutex);
9430 
9431 	/*
9432 	 * While this processor was waiting to acquire the asid set mutex,
9433 	 * pmap_reset_asid_set() running on another processor might have
9434 	 * updated this pmap's cookie to the current epoch.  In which case, we
9435 	 * don't need to allocate a new ASID.
9436 	 */
9437 	if (COOKIE_TO_EPOCH(pmap->pm_cookie) == set->asid_epoch)
9438 		goto out;
9439 
9440 	bit_ffc_at(set->asid_set, set->asid_next, set->asid_set_size,
9441 	    &new_asid);
9442 	if (new_asid == -1) {
9443 		bit_ffc_at(set->asid_set, ASID_FIRST_AVAILABLE,
9444 		    set->asid_next, &new_asid);
9445 		if (new_asid == -1) {
9446 			pmap_reset_asid_set(pmap);
9447 			bit_ffc_at(set->asid_set, ASID_FIRST_AVAILABLE,
9448 			    set->asid_set_size, &new_asid);
9449 			KASSERT(new_asid != -1, ("ASID allocation failure"));
9450 		}
9451 	}
9452 	bit_set(set->asid_set, new_asid);
9453 	set->asid_next = new_asid + 1;
9454 	pmap->pm_cookie = COOKIE_FROM(new_asid, set->asid_epoch);
9455 out:
9456 	mtx_unlock_spin(&set->asid_set_mutex);
9457 }
9458 
9459 static uint64_t __read_mostly ttbr_flags;
9460 
9461 /*
9462  * Compute the value that should be stored in ttbr0 to activate the specified
9463  * pmap.  This value may change from time to time.
9464  */
9465 uint64_t
9466 pmap_to_ttbr0(pmap_t pmap)
9467 {
9468 	uint64_t ttbr;
9469 
9470 	ttbr = pmap->pm_ttbr;
9471 	ttbr |= ASID_TO_OPERAND(COOKIE_TO_ASID(pmap->pm_cookie));
9472 	ttbr |= ttbr_flags;
9473 
9474 	return (ttbr);
9475 }
9476 
9477 static void
9478 pmap_set_cnp(void *arg)
9479 {
9480 	uint64_t ttbr0, ttbr1;
9481 	u_int cpuid;
9482 
9483 	cpuid = *(u_int *)arg;
9484 	if (cpuid == curcpu) {
9485 		/*
9486 		 * Set the flags while all CPUs are handling the
9487 		 * smp_rendezvous so will not call pmap_to_ttbr0. Any calls
9488 		 * to pmap_to_ttbr0 after this will have the CnP flag set.
9489 		 * The dsb after invalidating the TLB will act as a barrier
9490 		 * to ensure all CPUs can observe this change.
9491 		 */
9492 		ttbr_flags |= TTBR_CnP;
9493 	}
9494 
9495 	ttbr0 = READ_SPECIALREG(ttbr0_el1);
9496 	ttbr0 |= TTBR_CnP;
9497 
9498 	ttbr1 = READ_SPECIALREG(ttbr1_el1);
9499 	ttbr1 |= TTBR_CnP;
9500 
9501 	/* Update ttbr{0,1}_el1 with the CnP flag */
9502 	WRITE_SPECIALREG(ttbr0_el1, ttbr0);
9503 	WRITE_SPECIALREG(ttbr1_el1, ttbr1);
9504 	isb();
9505 	__asm __volatile("tlbi vmalle1is");
9506 	dsb(ish);
9507 	isb();
9508 }
9509 
9510 /*
9511  * Defer enabling some features until we have read the ID registers to know
9512  * if they are supported on all CPUs.
9513  */
9514 static void
9515 pmap_init_mp(void *dummy __unused)
9516 {
9517 	uint64_t reg;
9518 
9519 	get_kernel_reg(ID_AA64PFR1_EL1, &reg);
9520 	if (ID_AA64PFR1_BT_VAL(reg) != ID_AA64PFR1_BT_NONE) {
9521 		if (bootverbose)
9522 			printf("Enabling BTI\n");
9523 		pmap_bti_support = true;
9524 
9525 		pmap_bti_ranges_zone = uma_zcreate("BTI ranges",
9526 		    sizeof(struct rs_el), NULL, NULL, NULL, NULL,
9527 		    UMA_ALIGN_PTR, 0);
9528 	}
9529 }
9530 SYSINIT(pmap_init_mp, SI_SUB_CPU, SI_ORDER_ANY, pmap_init_mp, NULL);
9531 
9532 /*
9533  * Defer enabling CnP until we have read the ID registers to know if it's
9534  * supported on all CPUs.
9535  */
9536 static void
9537 pmap_init_cnp(void *dummy __unused)
9538 {
9539 	uint64_t reg;
9540 	u_int cpuid;
9541 
9542 	get_kernel_reg(ID_AA64MMFR2_EL1, &reg);
9543 	if (ID_AA64MMFR2_CnP_VAL(reg) != ID_AA64MMFR2_CnP_NONE) {
9544 		if (bootverbose)
9545 			printf("Enabling CnP\n");
9546 		cpuid = curcpu;
9547 		smp_rendezvous(NULL, pmap_set_cnp, NULL, &cpuid);
9548 	}
9549 
9550 }
9551 SYSINIT(pmap_init_cnp, SI_SUB_SMP, SI_ORDER_ANY, pmap_init_cnp, NULL);
9552 
9553 static bool
9554 pmap_activate_int(struct thread *td, pmap_t pmap)
9555 {
9556 	struct asid_set *set;
9557 	int epoch;
9558 
9559 	KASSERT(PCPU_GET(curpmap) != NULL, ("no active pmap"));
9560 	KASSERT(pmap != kernel_pmap, ("kernel pmap activation"));
9561 
9562 	if ((pmap->pm_stage == PM_STAGE1 && pmap == PCPU_GET(curpmap)) ||
9563 	    (pmap->pm_stage == PM_STAGE2 && pmap == PCPU_GET(curvmpmap))) {
9564 		/*
9565 		 * Handle the possibility that the old thread was preempted
9566 		 * after an "ic" or "tlbi" instruction but before it performed
9567 		 * a "dsb" instruction.  If the old thread migrates to a new
9568 		 * processor, its completion of a "dsb" instruction on that
9569 		 * new processor does not guarantee that the "ic" or "tlbi"
9570 		 * instructions performed on the old processor have completed.
9571 		 */
9572 		dsb(ish);
9573 		return (false);
9574 	}
9575 
9576 	set = pmap->pm_asid_set;
9577 	KASSERT(set != NULL, ("%s: NULL asid set", __func__));
9578 
9579 	/*
9580 	 * Ensure that the store to curpmap is globally visible before the
9581 	 * load from asid_epoch is performed.
9582 	 */
9583 	if (pmap->pm_stage == PM_STAGE1)
9584 		PCPU_SET(curpmap, pmap);
9585 	else
9586 		PCPU_SET(curvmpmap, pmap);
9587 	dsb(ish);
9588 	epoch = COOKIE_TO_EPOCH(pmap->pm_cookie);
9589 	if (epoch >= 0 && epoch != set->asid_epoch)
9590 		pmap_alloc_asid(pmap);
9591 
9592 	if (pmap->pm_stage == PM_STAGE1) {
9593 		uint64_t new_tcr, tcr;
9594 
9595 		new_tcr = td->td_proc->p_md.md_tcr;
9596 		tcr = READ_SPECIALREG(tcr_el1);
9597 		if ((tcr & MD_TCR_FIELDS) != new_tcr) {
9598 			tcr &= ~MD_TCR_FIELDS;
9599 			tcr |= new_tcr;
9600 			WRITE_SPECIALREG(tcr_el1, tcr);
9601 		}
9602 		set_ttbr0(pmap_to_ttbr0(pmap));
9603 		if (PCPU_GET(bcast_tlbi_workaround) != 0)
9604 			invalidate_local_icache();
9605 	}
9606 	return (true);
9607 }
9608 
9609 void
9610 pmap_activate_vm(pmap_t pmap)
9611 {
9612 
9613 	PMAP_ASSERT_STAGE2(pmap);
9614 
9615 	(void)pmap_activate_int(NULL, pmap);
9616 }
9617 
9618 void
9619 pmap_activate(struct thread *td)
9620 {
9621 	pmap_t	pmap;
9622 
9623 	pmap = vmspace_pmap(td->td_proc->p_vmspace);
9624 	PMAP_ASSERT_STAGE1(pmap);
9625 	critical_enter();
9626 	(void)pmap_activate_int(td, pmap);
9627 	critical_exit();
9628 }
9629 
9630 /*
9631  * Activate the thread we are switching to.
9632  * To simplify the assembly in cpu_throw return the new threads pcb.
9633  */
9634 struct pcb *
9635 pmap_switch(struct thread *new)
9636 {
9637 	pcpu_bp_harden bp_harden;
9638 	struct pcb *pcb;
9639 	uint64_t sctlr;
9640 
9641 	/* Store the new curthread */
9642 	PCPU_SET(curthread, new);
9643 
9644 	/* And the new pcb */
9645 	pcb = new->td_pcb;
9646 	PCPU_SET(curpcb, pcb);
9647 
9648 	if ((new->td_proc->p_flag & P_KPROC) == 0) {
9649 		sctlr = READ_SPECIALREG(sctlr_el1);
9650 		if ((sctlr & SCTLR_USER_MASK) != new->td_md.md_sctlr) {
9651 			sctlr &= ~SCTLR_USER_MASK;
9652 			sctlr |= new->td_md.md_sctlr;
9653 			WRITE_SPECIALREG(sctlr_el1, sctlr);
9654 			isb();
9655 		}
9656 	}
9657 
9658 	/*
9659 	 * TODO: We may need to flush the cache here if switching
9660 	 * to a user process.
9661 	 */
9662 
9663 	if (pmap_activate_int(new, vmspace_pmap(new->td_proc->p_vmspace))) {
9664 		/*
9665 		 * Stop userspace from training the branch predictor against
9666 		 * other processes. This will call into a CPU specific
9667 		 * function that clears the branch predictor state.
9668 		 */
9669 		bp_harden = PCPU_GET(bp_harden);
9670 		if (bp_harden != NULL)
9671 			bp_harden();
9672 	}
9673 
9674 	return (pcb);
9675 }
9676 
9677 void
9678 pmap_sync_icache(pmap_t pmap, vm_offset_t va, vm_size_t sz)
9679 {
9680 
9681 	PMAP_ASSERT_STAGE1(pmap);
9682 	KASSERT(ADDR_IS_CANONICAL(va),
9683 	    ("%s: Address not in canonical form: %lx", __func__, va));
9684 
9685 	if (ADDR_IS_KERNEL(va)) {
9686 		cpu_icache_sync_range((void *)va, sz);
9687 	} else {
9688 		u_int len, offset;
9689 		vm_paddr_t pa;
9690 
9691 		/* Find the length of data in this page to flush */
9692 		offset = va & PAGE_MASK;
9693 		len = imin(PAGE_SIZE - offset, sz);
9694 
9695 		while (sz != 0) {
9696 			/* Extract the physical address & find it in the DMAP */
9697 			pa = pmap_extract(pmap, va);
9698 			if (pa != 0)
9699 				cpu_icache_sync_range(PHYS_TO_DMAP(pa), len);
9700 
9701 			/* Move to the next page */
9702 			sz -= len;
9703 			va += len;
9704 			/* Set the length for the next iteration */
9705 			len = imin(PAGE_SIZE, sz);
9706 		}
9707 	}
9708 }
9709 
9710 static int
9711 pmap_stage2_fault(pmap_t pmap, uint64_t esr, uint64_t far)
9712 {
9713 	pd_entry_t *pdep;
9714 	pt_entry_t *ptep, pte;
9715 	int rv, lvl, dfsc;
9716 
9717 	PMAP_ASSERT_STAGE2(pmap);
9718 	rv = KERN_FAILURE;
9719 
9720 	/* Data and insn aborts use same encoding for FSC field. */
9721 	dfsc = esr & ISS_DATA_DFSC_MASK;
9722 	switch (dfsc) {
9723 	case ISS_DATA_DFSC_TF_L0:
9724 	case ISS_DATA_DFSC_TF_L1:
9725 	case ISS_DATA_DFSC_TF_L2:
9726 	case ISS_DATA_DFSC_TF_L3:
9727 		PMAP_LOCK(pmap);
9728 		pdep = pmap_pde(pmap, far, &lvl);
9729 		if (pdep == NULL || lvl != (dfsc - ISS_DATA_DFSC_TF_L1)) {
9730 			PMAP_UNLOCK(pmap);
9731 			break;
9732 		}
9733 
9734 		switch (lvl) {
9735 		case 0:
9736 			ptep = pmap_l0_to_l1(pdep, far);
9737 			break;
9738 		case 1:
9739 			ptep = pmap_l1_to_l2(pdep, far);
9740 			break;
9741 		case 2:
9742 			ptep = pmap_l2_to_l3(pdep, far);
9743 			break;
9744 		default:
9745 			panic("%s: Invalid pde level %d", __func__,lvl);
9746 		}
9747 		goto fault_exec;
9748 
9749 	case ISS_DATA_DFSC_AFF_L1:
9750 	case ISS_DATA_DFSC_AFF_L2:
9751 	case ISS_DATA_DFSC_AFF_L3:
9752 		PMAP_LOCK(pmap);
9753 		ptep = pmap_pte(pmap, far, &lvl);
9754 fault_exec:
9755 		if (ptep != NULL && (pte = pmap_load(ptep)) != 0) {
9756 			/*
9757 			 * If accessing an executable page invalidate
9758 			 * the I-cache so it will be valid when we
9759 			 * continue execution in the guest. The D-cache
9760 			 * is assumed to already be clean to the Point
9761 			 * of Coherency.
9762 			 */
9763 			if ((pte & ATTR_S2_XN_MASK) !=
9764 			    ATTR_S2_XN(ATTR_S2_XN_ALL)) {
9765 				invalidate_icache();
9766 			}
9767 			pmap_set_bits(ptep, ATTR_AF | ATTR_DESCR_VALID);
9768 			rv = KERN_SUCCESS;
9769 		}
9770 		PMAP_UNLOCK(pmap);
9771 		break;
9772 	}
9773 
9774 	return (rv);
9775 }
9776 
9777 int
9778 pmap_fault(pmap_t pmap, uint64_t esr, uint64_t far)
9779 {
9780 	pt_entry_t pte, *ptep;
9781 	register_t intr;
9782 	uint64_t ec, par;
9783 	int lvl, rv;
9784 
9785 	rv = KERN_FAILURE;
9786 
9787 	ec = ESR_ELx_EXCEPTION(esr);
9788 	switch (ec) {
9789 	case EXCP_INSN_ABORT_L:
9790 	case EXCP_INSN_ABORT:
9791 	case EXCP_DATA_ABORT_L:
9792 	case EXCP_DATA_ABORT:
9793 		break;
9794 	default:
9795 		return (rv);
9796 	}
9797 
9798 	if (pmap->pm_stage == PM_STAGE2)
9799 		return (pmap_stage2_fault(pmap, esr, far));
9800 
9801 	/* Data and insn aborts use same encoding for FSC field. */
9802 	switch (esr & ISS_DATA_DFSC_MASK) {
9803 	case ISS_DATA_DFSC_AFF_L1:
9804 	case ISS_DATA_DFSC_AFF_L2:
9805 	case ISS_DATA_DFSC_AFF_L3:
9806 		PMAP_LOCK(pmap);
9807 		ptep = pmap_pte(pmap, far, &lvl);
9808 		if (ptep != NULL) {
9809 			pmap_set_bits(ptep, ATTR_AF);
9810 			rv = KERN_SUCCESS;
9811 			/*
9812 			 * XXXMJ as an optimization we could mark the entry
9813 			 * dirty if this is a write fault.
9814 			 */
9815 		}
9816 		PMAP_UNLOCK(pmap);
9817 		break;
9818 	case ISS_DATA_DFSC_PF_L1:
9819 	case ISS_DATA_DFSC_PF_L2:
9820 	case ISS_DATA_DFSC_PF_L3:
9821 		if ((ec != EXCP_DATA_ABORT_L && ec != EXCP_DATA_ABORT) ||
9822 		    (esr & ISS_DATA_WnR) == 0)
9823 			return (rv);
9824 		PMAP_LOCK(pmap);
9825 		ptep = pmap_pte(pmap, far, &lvl);
9826 		if (ptep != NULL &&
9827 		    ((pte = pmap_load(ptep)) & ATTR_SW_DBM) != 0) {
9828 			if ((pte & ATTR_S1_AP_RW_BIT) ==
9829 			    ATTR_S1_AP(ATTR_S1_AP_RO)) {
9830 				pmap_clear_bits(ptep, ATTR_S1_AP_RW_BIT);
9831 				pmap_s1_invalidate_page(pmap, far, true);
9832 			}
9833 			rv = KERN_SUCCESS;
9834 		}
9835 		PMAP_UNLOCK(pmap);
9836 		break;
9837 	case ISS_DATA_DFSC_TF_L0:
9838 	case ISS_DATA_DFSC_TF_L1:
9839 	case ISS_DATA_DFSC_TF_L2:
9840 	case ISS_DATA_DFSC_TF_L3:
9841 		/*
9842 		 * Retry the translation.  A break-before-make sequence can
9843 		 * produce a transient fault.
9844 		 */
9845 		if (pmap == kernel_pmap) {
9846 			/*
9847 			 * The translation fault may have occurred within a
9848 			 * critical section.  Therefore, we must check the
9849 			 * address without acquiring the kernel pmap's lock.
9850 			 */
9851 			if (pmap_klookup(far, NULL))
9852 				rv = KERN_SUCCESS;
9853 		} else {
9854 			bool owned;
9855 
9856 			/*
9857 			 * In the EFIRT driver we lock the pmap before
9858 			 * calling into the runtime service. As the lock
9859 			 * is already owned by the current thread skip
9860 			 * locking it again.
9861 			 */
9862 			owned = PMAP_OWNED(pmap);
9863 			if (!owned)
9864 				PMAP_LOCK(pmap);
9865 			/* Ask the MMU to check the address. */
9866 			intr = intr_disable();
9867 			par = arm64_address_translate_s1e0r(far);
9868 			intr_restore(intr);
9869 			if (!owned)
9870 				PMAP_UNLOCK(pmap);
9871 
9872 			/*
9873 			 * If the translation was successful, then we can
9874 			 * return success to the trap handler.
9875 			 */
9876 			if (PAR_SUCCESS(par))
9877 				rv = KERN_SUCCESS;
9878 		}
9879 		break;
9880 	}
9881 
9882 	return (rv);
9883 }
9884 
9885 /*
9886  *	Increase the starting virtual address of the given mapping if a
9887  *	different alignment might result in more superpage mappings.
9888  */
9889 void
9890 pmap_align_superpage(vm_object_t object, vm_ooffset_t offset,
9891     vm_offset_t *addr, vm_size_t size)
9892 {
9893 	vm_offset_t superpage_offset;
9894 
9895 	if (size < L3C_SIZE)
9896 		return;
9897 	if (object != NULL && (object->flags & OBJ_COLORED) != 0)
9898 		offset += ptoa(object->pg_color);
9899 
9900 	/*
9901 	 * Considering the object's physical alignment, is the mapping large
9902 	 * enough to encompass an L2 (2MB/32MB) superpage ...
9903 	 */
9904 	superpage_offset = offset & L2_OFFSET;
9905 	if (size - ((L2_SIZE - superpage_offset) & L2_OFFSET) >= L2_SIZE) {
9906 		/*
9907 		 * If the virtual and physical alignments differ, then
9908 		 * increase the virtual address so that the alignments match.
9909 		 */
9910 		if ((*addr & L2_OFFSET) < superpage_offset)
9911 			*addr = (*addr & ~L2_OFFSET) + superpage_offset;
9912 		else if ((*addr & L2_OFFSET) > superpage_offset)
9913 			*addr = ((*addr + L2_OFFSET) & ~L2_OFFSET) +
9914 			    superpage_offset;
9915 		return;
9916 	}
9917 	/* ... or an L3C (64KB/2MB) superpage? */
9918 	superpage_offset = offset & L3C_OFFSET;
9919 	if (size - ((L3C_SIZE - superpage_offset) & L3C_OFFSET) >= L3C_SIZE) {
9920 		if ((*addr & L3C_OFFSET) < superpage_offset)
9921 			*addr = (*addr & ~L3C_OFFSET) + superpage_offset;
9922 		else if ((*addr & L3C_OFFSET) > superpage_offset)
9923 			*addr = ((*addr + L3C_OFFSET) & ~L3C_OFFSET) +
9924 			    superpage_offset;
9925 	}
9926 }
9927 
9928 /**
9929  * Get the kernel virtual address of a set of physical pages. If there are
9930  * physical addresses not covered by the DMAP perform a transient mapping
9931  * that will be removed when calling pmap_unmap_io_transient.
9932  *
9933  * \param page        The pages the caller wishes to obtain the virtual
9934  *                    address on the kernel memory map.
9935  * \param vaddr       On return contains the kernel virtual memory address
9936  *                    of the pages passed in the page parameter.
9937  * \param count       Number of pages passed in.
9938  * \param can_fault   true if the thread using the mapped pages can take
9939  *                    page faults, false otherwise.
9940  *
9941  * \returns true if the caller must call pmap_unmap_io_transient when
9942  *          finished or false otherwise.
9943  *
9944  */
9945 bool
9946 pmap_map_io_transient(vm_page_t page[], void *vaddr[], int count,
9947     bool can_fault)
9948 {
9949 	vm_paddr_t paddr;
9950 	vmem_addr_t addr;
9951 	bool needs_mapping;
9952 	int error __diagused, i;
9953 
9954 	/*
9955 	 * Allocate any KVA space that we need, this is done in a separate
9956 	 * loop to prevent calling vmem_alloc while pinned.
9957 	 */
9958 	needs_mapping = false;
9959 	for (i = 0; i < count; i++) {
9960 		paddr = VM_PAGE_TO_PHYS(page[i]);
9961 		if (__predict_false(!PHYS_IN_DMAP(paddr))) {
9962 			error = vmem_alloc(kernel_arena, PAGE_SIZE,
9963 			    M_BESTFIT | M_WAITOK, &addr);
9964 			KASSERT(error == 0, ("vmem_alloc failed: %d", error));
9965 			vaddr[i] = (void *)addr;
9966 			needs_mapping = true;
9967 		} else {
9968 			vaddr[i] = PHYS_TO_DMAP(paddr);
9969 		}
9970 	}
9971 
9972 	/* Exit early if everything is covered by the DMAP */
9973 	if (!needs_mapping)
9974 		return (false);
9975 
9976 	if (!can_fault)
9977 		sched_pin();
9978 	for (i = 0; i < count; i++) {
9979 		paddr = VM_PAGE_TO_PHYS(page[i]);
9980 		if (!PHYS_IN_DMAP(paddr)) {
9981 			panic(
9982 			   "pmap_map_io_transient: TODO: Map out of DMAP data");
9983 		}
9984 	}
9985 
9986 	return (needs_mapping);
9987 }
9988 
9989 void
9990 pmap_unmap_io_transient(vm_page_t page[], void *vaddr[], int count,
9991     bool can_fault)
9992 {
9993 	vm_paddr_t paddr;
9994 	int i;
9995 
9996 	if (!can_fault)
9997 		sched_unpin();
9998 	for (i = 0; i < count; i++) {
9999 		paddr = VM_PAGE_TO_PHYS(page[i]);
10000 		if (!PHYS_IN_DMAP(paddr)) {
10001 			panic("ARM64TODO: pmap_unmap_io_transient: Unmap data");
10002 		}
10003 	}
10004 }
10005 
10006 bool
10007 pmap_is_valid_memattr(pmap_t pmap __unused, vm_memattr_t mode)
10008 {
10009 
10010 	return (mode >= 0 && mode < VM_MEMATTR_END);
10011 }
10012 
10013 static void *
10014 bti_dup_range(void *ctx __unused, void *data)
10015 {
10016 	struct rs_el *node, *new_node;
10017 
10018 	new_node = uma_zalloc(pmap_bti_ranges_zone, M_NOWAIT);
10019 	if (new_node == NULL)
10020 		return (NULL);
10021 	node = data;
10022 	memcpy(new_node, node, sizeof(*node));
10023 	return (new_node);
10024 }
10025 
10026 static void
10027 bti_free_range(void *ctx __unused, void *node)
10028 {
10029 
10030 	uma_zfree(pmap_bti_ranges_zone, node);
10031 }
10032 
10033 static int
10034 pmap_bti_assign(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
10035 {
10036 	struct rs_el *rs;
10037 	int error;
10038 
10039 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
10040 	PMAP_ASSERT_STAGE1(pmap);
10041 	MPASS(pmap->pm_bti != NULL);
10042 	rs = uma_zalloc(pmap_bti_ranges_zone, M_NOWAIT);
10043 	if (rs == NULL)
10044 		return (ENOMEM);
10045 	error = rangeset_insert(pmap->pm_bti, sva, eva, rs);
10046 	if (error != 0)
10047 		uma_zfree(pmap_bti_ranges_zone, rs);
10048 	return (error);
10049 }
10050 
10051 static void
10052 pmap_bti_deassign_all(pmap_t pmap)
10053 {
10054 
10055 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
10056 	if (pmap->pm_bti != NULL)
10057 		rangeset_remove_all(pmap->pm_bti);
10058 }
10059 
10060 /*
10061  * Returns true if the BTI setting is the same across the specified address
10062  * range, and false otherwise.  When returning true, updates the referenced PTE
10063  * to reflect the BTI setting.
10064  *
10065  * Only stage 1 pmaps support BTI.  The kernel pmap is always a stage 1 pmap
10066  * that has the same BTI setting implicitly across its entire address range.
10067  */
10068 static bool
10069 pmap_bti_same(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, pt_entry_t *pte)
10070 {
10071 	struct rs_el *rs;
10072 	vm_offset_t va;
10073 
10074 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
10075 	KASSERT(ADDR_IS_CANONICAL(sva),
10076 	    ("%s: Start address not in canonical form: %lx", __func__, sva));
10077 	KASSERT(ADDR_IS_CANONICAL(eva),
10078 	    ("%s: End address not in canonical form: %lx", __func__, eva));
10079 	KASSERT((*pte & ATTR_S1_GP) == 0,
10080 	    ("%s: pte %lx has ATTR_S1_GP preset", __func__, *pte));
10081 
10082 	if (pmap == kernel_pmap) {
10083 		*pte |= ATTR_KERN_GP;
10084 		return (true);
10085 	}
10086 	if (pmap->pm_bti == NULL)
10087 		return (true);
10088 	PMAP_ASSERT_STAGE1(pmap);
10089 	rs = rangeset_containing(pmap->pm_bti, sva);
10090 	if (rs == NULL)
10091 		return (rangeset_empty(pmap->pm_bti, sva, eva));
10092 	while ((va = rs->re_end) < eva) {
10093 		if ((rs = rangeset_beginning(pmap->pm_bti, va)) == NULL)
10094 			return (false);
10095 	}
10096 	*pte |= ATTR_S1_GP;
10097 	return (true);
10098 }
10099 
10100 static pt_entry_t
10101 pmap_pte_bti(pmap_t pmap, vm_offset_t va)
10102 {
10103 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
10104 	MPASS(ADDR_IS_CANONICAL(va));
10105 
10106 	if (pmap->pm_stage != PM_STAGE1)
10107 		return (0);
10108 	if (pmap == kernel_pmap)
10109 		return (ATTR_KERN_GP);
10110 	if (pmap->pm_bti != NULL &&
10111 	    rangeset_containing(pmap->pm_bti, va) != NULL)
10112 		return (ATTR_S1_GP);
10113 	return (0);
10114 }
10115 
10116 static void
10117 pmap_bti_on_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
10118 {
10119 
10120 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
10121 	if (pmap->pm_bti != NULL)
10122 		rangeset_remove(pmap->pm_bti, sva, eva);
10123 }
10124 
10125 static int
10126 pmap_bti_copy(pmap_t dst_pmap, pmap_t src_pmap)
10127 {
10128 
10129 	PMAP_LOCK_ASSERT(dst_pmap, MA_OWNED);
10130 	PMAP_LOCK_ASSERT(src_pmap, MA_OWNED);
10131 	MPASS(src_pmap->pm_stage == dst_pmap->pm_stage);
10132 	MPASS(src_pmap->pm_bti != NULL);
10133 	MPASS(dst_pmap->pm_bti != NULL);
10134 	if (src_pmap->pm_bti->rs_data_ctx == NULL)
10135 		return (0);
10136 	return (rangeset_copy(dst_pmap->pm_bti, src_pmap->pm_bti));
10137 }
10138 
10139 static void
10140 pmap_bti_update_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, bool set)
10141 {
10142 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
10143 	PMAP_ASSERT_STAGE1(pmap);
10144 
10145 	pmap_mask_set_locked(pmap, sva, eva, ATTR_S1_GP, set ? ATTR_S1_GP : 0,
10146 	    true);
10147 }
10148 
10149 int
10150 pmap_bti_set(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
10151 {
10152 	int error;
10153 
10154 	if (pmap->pm_bti == NULL)
10155 		return (0);
10156 	if (!ADDR_IS_CANONICAL(sva) || !ADDR_IS_CANONICAL(eva))
10157 		return (EINVAL);
10158 	if (pmap->pm_stage != PM_STAGE1)
10159 		return (EINVAL);
10160 	if (eva <= sva || ADDR_IS_KERNEL(eva))
10161 		return (EFAULT);
10162 
10163 	sva = trunc_page(sva);
10164 	eva = round_page(eva);
10165 	for (;;) {
10166 		PMAP_LOCK(pmap);
10167 		error = pmap_bti_assign(pmap, sva, eva);
10168 		if (error == 0)
10169 			pmap_bti_update_range(pmap, sva, eva, true);
10170 		PMAP_UNLOCK(pmap);
10171 		if (error != ENOMEM)
10172 			break;
10173 		vm_wait(NULL);
10174 	}
10175 	return (error);
10176 }
10177 
10178 #if defined(KASAN) || defined(KMSAN)
10179 static pd_entry_t	*pmap_san_early_l2;
10180 
10181 #define	SAN_BOOTSTRAP_L2_SIZE	(1 * L2_SIZE)
10182 #define	SAN_BOOTSTRAP_SIZE	(2 * PAGE_SIZE)
10183 static vm_offset_t __nosanitizeaddress
10184 pmap_san_enter_bootstrap_alloc_l2(void)
10185 {
10186 	static uint8_t bootstrap_data[SAN_BOOTSTRAP_L2_SIZE] __aligned(L2_SIZE);
10187 	static size_t offset = 0;
10188 	vm_offset_t addr;
10189 
10190 	if (offset + L2_SIZE > sizeof(bootstrap_data)) {
10191 		panic("%s: out of memory for the bootstrap shadow map L2 entries",
10192 		    __func__);
10193 	}
10194 
10195 	addr = (uintptr_t)&bootstrap_data[offset];
10196 	offset += L2_SIZE;
10197 	return (addr);
10198 }
10199 
10200 /*
10201  * SAN L1 + L2 pages, maybe L3 entries later?
10202  */
10203 static vm_offset_t __nosanitizeaddress
10204 pmap_san_enter_bootstrap_alloc_pages(int npages)
10205 {
10206 	static uint8_t bootstrap_data[SAN_BOOTSTRAP_SIZE] __aligned(PAGE_SIZE);
10207 	static size_t offset = 0;
10208 	vm_offset_t addr;
10209 
10210 	if (offset + (npages * PAGE_SIZE) > sizeof(bootstrap_data)) {
10211 		panic("%s: out of memory for the bootstrap shadow map",
10212 		    __func__);
10213 	}
10214 
10215 	addr = (uintptr_t)&bootstrap_data[offset];
10216 	offset += (npages * PAGE_SIZE);
10217 	return (addr);
10218 }
10219 
10220 static void __nosanitizeaddress
10221 pmap_san_enter_bootstrap(void)
10222 {
10223 	vm_offset_t freemempos;
10224 
10225 	/* L1, L2 */
10226 	freemempos = pmap_san_enter_bootstrap_alloc_pages(2);
10227 	bs_state.freemempos = freemempos;
10228 	bs_state.va = KASAN_MIN_ADDRESS;
10229 	pmap_bootstrap_l1_table(&bs_state);
10230 	pmap_san_early_l2 = bs_state.l2;
10231 }
10232 
10233 static vm_page_t
10234 pmap_san_enter_alloc_l3(void)
10235 {
10236 	vm_page_t m;
10237 
10238 	m = vm_page_alloc_noobj(VM_ALLOC_INTERRUPT | VM_ALLOC_WIRED |
10239 	    VM_ALLOC_ZERO);
10240 	if (m == NULL)
10241 		panic("%s: no memory to grow shadow map", __func__);
10242 	return (m);
10243 }
10244 
10245 static vm_page_t
10246 pmap_san_enter_alloc_l2(void)
10247 {
10248 	return (vm_page_alloc_noobj_contig(VM_ALLOC_WIRED | VM_ALLOC_ZERO,
10249 	    Ln_ENTRIES, 0, ~0ul, L2_SIZE, 0, VM_MEMATTR_DEFAULT));
10250 }
10251 
10252 void __nosanitizeaddress __nosanitizememory
10253 pmap_san_enter(vm_offset_t va)
10254 {
10255 	pd_entry_t *l1, *l2;
10256 	pt_entry_t *l3;
10257 	vm_page_t m;
10258 
10259 	if (virtual_avail == 0) {
10260 		vm_offset_t block;
10261 		int slot;
10262 		bool first;
10263 
10264 		/* Temporary shadow map prior to pmap_bootstrap(). */
10265 		first = pmap_san_early_l2 == NULL;
10266 		if (first)
10267 			pmap_san_enter_bootstrap();
10268 
10269 		l2 = pmap_san_early_l2;
10270 		slot = pmap_l2_index(va);
10271 
10272 		if ((pmap_load(&l2[slot]) & ATTR_DESCR_VALID) == 0) {
10273 			MPASS(first);
10274 			block = pmap_san_enter_bootstrap_alloc_l2();
10275 			pmap_store(&l2[slot],
10276 			    PHYS_TO_PTE(pmap_early_vtophys(block)) |
10277 			    PMAP_SAN_PTE_BITS | L2_BLOCK);
10278 			dmb(ishst);
10279 		}
10280 
10281 		return;
10282 	}
10283 
10284 	mtx_assert(&kernel_map->system_mtx, MA_OWNED);
10285 	l1 = pmap_l1(kernel_pmap, va);
10286 	MPASS(l1 != NULL);
10287 	if ((pmap_load(l1) & ATTR_DESCR_VALID) == 0) {
10288 		m = pmap_san_enter_alloc_l3();
10289 		pmap_store(l1, VM_PAGE_TO_PTE(m) | L1_TABLE);
10290 	}
10291 	l2 = pmap_l1_to_l2(l1, va);
10292 	if ((pmap_load(l2) & ATTR_DESCR_VALID) == 0) {
10293 		m = pmap_san_enter_alloc_l2();
10294 		if (m != NULL) {
10295 			pmap_store(l2, VM_PAGE_TO_PTE(m) |
10296 			    PMAP_SAN_PTE_BITS | L2_BLOCK);
10297 		} else {
10298 			m = pmap_san_enter_alloc_l3();
10299 			pmap_store(l2, VM_PAGE_TO_PTE(m) | L2_TABLE);
10300 		}
10301 		dmb(ishst);
10302 	}
10303 	if ((pmap_load(l2) & ATTR_DESCR_MASK) == L2_BLOCK)
10304 		return;
10305 	l3 = pmap_l2_to_l3(l2, va);
10306 	if ((pmap_load(l3) & ATTR_DESCR_VALID) != 0)
10307 		return;
10308 	m = pmap_san_enter_alloc_l3();
10309 	pmap_store(l3, VM_PAGE_TO_PTE(m) | PMAP_SAN_PTE_BITS | L3_PAGE);
10310 	dmb(ishst);
10311 }
10312 #endif /* KASAN || KMSAN */
10313 
10314 /*
10315  * Track a range of the kernel's virtual address space that is contiguous
10316  * in various mapping attributes.
10317  */
10318 struct pmap_kernel_map_range {
10319 	vm_offset_t sva;
10320 	pt_entry_t attrs;
10321 	int l3pages;
10322 	int l3contig;
10323 	int l2blocks;
10324 	int l2contig;
10325 	int l1blocks;
10326 };
10327 
10328 static void
10329 sysctl_kmaps_dump(struct sbuf *sb, struct pmap_kernel_map_range *range,
10330     vm_offset_t eva)
10331 {
10332 	const char *mode;
10333 	int index;
10334 
10335 	if (eva <= range->sva)
10336 		return;
10337 
10338 	index = range->attrs & ATTR_S1_IDX_MASK;
10339 	switch (index) {
10340 	case ATTR_S1_IDX(VM_MEMATTR_DEVICE_NP):
10341 		mode = "DEV-NP";
10342 		break;
10343 	case ATTR_S1_IDX(VM_MEMATTR_DEVICE):
10344 		mode = "DEV";
10345 		break;
10346 	case ATTR_S1_IDX(VM_MEMATTR_UNCACHEABLE):
10347 		mode = "UC";
10348 		break;
10349 	case ATTR_S1_IDX(VM_MEMATTR_WRITE_BACK):
10350 		mode = "WB";
10351 		break;
10352 	case ATTR_S1_IDX(VM_MEMATTR_WRITE_THROUGH):
10353 		mode = "WT";
10354 		break;
10355 	case ATTR_S1_IDX(VM_MEMATTR_TAGGED):
10356 		mode = "TAGGED";
10357 		break;
10358 	default:
10359 		printf(
10360 		    "%s: unknown memory type %x for range 0x%016lx-0x%016lx\n",
10361 		    __func__, index, range->sva, eva);
10362 		mode = "??";
10363 		break;
10364 	}
10365 
10366 	sbuf_printf(sb, "0x%016lx-0x%016lx r%c%c%c%c%c %6s %d %d %d %d %d\n",
10367 	    range->sva, eva,
10368 	    (range->attrs & ATTR_S1_AP_RW_BIT) == ATTR_S1_AP_RW ? 'w' : '-',
10369 	    (range->attrs & ATTR_S1_PXN) != 0 ? '-' : 'x',
10370 	    (range->attrs & ATTR_S1_UXN) != 0 ? '-' : 'X',
10371 	    (range->attrs & ATTR_S1_AP(ATTR_S1_AP_USER)) != 0 ? 'u' : 's',
10372 	    (range->attrs & ATTR_S1_GP) != 0 ? 'g' : '-',
10373 	    mode, range->l1blocks, range->l2contig, range->l2blocks,
10374 	    range->l3contig, range->l3pages);
10375 
10376 	/* Reset to sentinel value. */
10377 	range->sva = 0xfffffffffffffffful;
10378 }
10379 
10380 /*
10381  * Determine whether the attributes specified by a page table entry match those
10382  * being tracked by the current range.
10383  */
10384 static bool
10385 sysctl_kmaps_match(struct pmap_kernel_map_range *range, pt_entry_t attrs)
10386 {
10387 
10388 	return (range->attrs == attrs);
10389 }
10390 
10391 static void
10392 sysctl_kmaps_reinit(struct pmap_kernel_map_range *range, vm_offset_t va,
10393     pt_entry_t attrs)
10394 {
10395 
10396 	memset(range, 0, sizeof(*range));
10397 	range->sva = va;
10398 	range->attrs = attrs;
10399 }
10400 
10401 /* Get the block/page attributes that correspond to the table attributes */
10402 static pt_entry_t
10403 sysctl_kmaps_table_attrs(pd_entry_t table)
10404 {
10405 	pt_entry_t attrs;
10406 
10407 	attrs = 0;
10408 	if ((table & TATTR_UXN_TABLE) != 0)
10409 		attrs |= ATTR_S1_UXN;
10410 	if ((table & TATTR_PXN_TABLE) != 0)
10411 		attrs |= ATTR_S1_PXN;
10412 	if ((table & TATTR_AP_TABLE_RO) != 0)
10413 		attrs |= ATTR_S1_AP(ATTR_S1_AP_RO);
10414 
10415 	return (attrs);
10416 }
10417 
10418 /* Read the block/page attributes we care about */
10419 static pt_entry_t
10420 sysctl_kmaps_block_attrs(pt_entry_t block)
10421 {
10422 	return (block & (ATTR_S1_AP_MASK | ATTR_S1_XN | ATTR_S1_IDX_MASK |
10423 	    ATTR_S1_GP));
10424 }
10425 
10426 /*
10427  * Given a leaf PTE, derive the mapping's attributes.  If they do not match
10428  * those of the current run, dump the address range and its attributes, and
10429  * begin a new run.
10430  */
10431 static void
10432 sysctl_kmaps_check(struct sbuf *sb, struct pmap_kernel_map_range *range,
10433     vm_offset_t va, pd_entry_t l0e, pd_entry_t l1e, pd_entry_t l2e,
10434     pt_entry_t l3e)
10435 {
10436 	pt_entry_t attrs;
10437 
10438 	attrs = sysctl_kmaps_table_attrs(l0e);
10439 
10440 	if ((l1e & ATTR_DESCR_TYPE_MASK) == ATTR_DESCR_TYPE_BLOCK) {
10441 		attrs |= sysctl_kmaps_block_attrs(l1e);
10442 		goto done;
10443 	}
10444 	attrs |= sysctl_kmaps_table_attrs(l1e);
10445 
10446 	if ((l2e & ATTR_DESCR_TYPE_MASK) == ATTR_DESCR_TYPE_BLOCK) {
10447 		attrs |= sysctl_kmaps_block_attrs(l2e);
10448 		goto done;
10449 	}
10450 	attrs |= sysctl_kmaps_table_attrs(l2e);
10451 	attrs |= sysctl_kmaps_block_attrs(l3e);
10452 
10453 done:
10454 	if (range->sva > va || !sysctl_kmaps_match(range, attrs)) {
10455 		sysctl_kmaps_dump(sb, range, va);
10456 		sysctl_kmaps_reinit(range, va, attrs);
10457 	}
10458 }
10459 
10460 static int
10461 sysctl_kmaps(SYSCTL_HANDLER_ARGS)
10462 {
10463 	struct pmap_kernel_map_range range;
10464 	struct sbuf sbuf, *sb;
10465 	pd_entry_t l0e, *l1, l1e, *l2, l2e;
10466 	pt_entry_t *l3, l3e;
10467 	vm_offset_t sva;
10468 	vm_paddr_t pa;
10469 	int error, i, j, k, l;
10470 
10471 	error = sysctl_wire_old_buffer(req, 0);
10472 	if (error != 0)
10473 		return (error);
10474 	sb = &sbuf;
10475 	sbuf_new_for_sysctl(sb, NULL, PAGE_SIZE, req);
10476 
10477 	/* Sentinel value. */
10478 	range.sva = 0xfffffffffffffffful;
10479 
10480 	/*
10481 	 * Iterate over the kernel page tables without holding the kernel pmap
10482 	 * lock.  Kernel page table pages are never freed, so at worst we will
10483 	 * observe inconsistencies in the output.
10484 	 */
10485 	for (sva = 0xffff000000000000ul, i = pmap_l0_index(sva); i < Ln_ENTRIES;
10486 	    i++) {
10487 		if (i == pmap_l0_index(DMAP_MIN_ADDRESS))
10488 			sbuf_printf(sb, "\nDirect map:\n");
10489 		else if (i == pmap_l0_index(VM_MIN_KERNEL_ADDRESS))
10490 			sbuf_printf(sb, "\nKernel map:\n");
10491 #ifdef KASAN
10492 		else if (i == pmap_l0_index(KASAN_MIN_ADDRESS))
10493 			sbuf_printf(sb, "\nKASAN shadow map:\n");
10494 #endif
10495 #ifdef KMSAN
10496 		else if (i == pmap_l0_index(KMSAN_SHAD_MIN_ADDRESS))
10497 			sbuf_printf(sb, "\nKMSAN shadow map:\n");
10498 		else if (i == pmap_l0_index(KMSAN_ORIG_MIN_ADDRESS))
10499 			sbuf_printf(sb, "\nKMSAN origin map:\n");
10500 #endif
10501 
10502 		l0e = kernel_pmap->pm_l0[i];
10503 		if ((l0e & ATTR_DESCR_VALID) == 0) {
10504 			sysctl_kmaps_dump(sb, &range, sva);
10505 			sva += L0_SIZE;
10506 			continue;
10507 		}
10508 		pa = PTE_TO_PHYS(l0e);
10509 		l1 = PHYS_TO_DMAP(pa);
10510 
10511 		for (j = pmap_l1_index(sva); j < Ln_ENTRIES; j++) {
10512 			l1e = l1[j];
10513 			if ((l1e & ATTR_DESCR_VALID) == 0) {
10514 				sysctl_kmaps_dump(sb, &range, sva);
10515 				sva += L1_SIZE;
10516 				continue;
10517 			}
10518 			if ((l1e & ATTR_DESCR_MASK) == L1_BLOCK) {
10519 				PMAP_ASSERT_L1_BLOCKS_SUPPORTED;
10520 				sysctl_kmaps_check(sb, &range, sva, l0e, l1e,
10521 				    0, 0);
10522 				range.l1blocks++;
10523 				sva += L1_SIZE;
10524 				continue;
10525 			}
10526 			pa = PTE_TO_PHYS(l1e);
10527 			l2 = PHYS_TO_DMAP(pa);
10528 
10529 			for (k = pmap_l2_index(sva); k < Ln_ENTRIES; k++) {
10530 				l2e = l2[k];
10531 				if ((l2e & ATTR_DESCR_VALID) == 0) {
10532 					sysctl_kmaps_dump(sb, &range, sva);
10533 					sva += L2_SIZE;
10534 					continue;
10535 				}
10536 				if ((l2e & ATTR_DESCR_MASK) == L2_BLOCK) {
10537 					sysctl_kmaps_check(sb, &range, sva,
10538 					    l0e, l1e, l2e, 0);
10539 					if ((l2e & ATTR_CONTIGUOUS) != 0)
10540 						range.l2contig +=
10541 						    k % L2C_ENTRIES == 0 ?
10542 						    1 : 0;
10543 					else
10544 						range.l2blocks++;
10545 					sva += L2_SIZE;
10546 					continue;
10547 				}
10548 				pa = PTE_TO_PHYS(l2e);
10549 				l3 = PHYS_TO_DMAP(pa);
10550 
10551 				for (l = pmap_l3_index(sva); l < Ln_ENTRIES;
10552 				    l++, sva += L3_SIZE) {
10553 					l3e = l3[l];
10554 					if ((l3e & ATTR_DESCR_VALID) == 0) {
10555 						sysctl_kmaps_dump(sb, &range,
10556 						    sva);
10557 						continue;
10558 					}
10559 					sysctl_kmaps_check(sb, &range, sva,
10560 					    l0e, l1e, l2e, l3e);
10561 					if ((l3e & ATTR_CONTIGUOUS) != 0)
10562 						range.l3contig +=
10563 						    l % L3C_ENTRIES == 0 ?
10564 						    1 : 0;
10565 					else
10566 						range.l3pages++;
10567 				}
10568 			}
10569 		}
10570 	}
10571 
10572 	error = sbuf_finish(sb);
10573 	sbuf_delete(sb);
10574 	return (error);
10575 }
10576 SYSCTL_OID(_vm_pmap, OID_AUTO, kernel_maps,
10577     CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE | CTLFLAG_SKIP,
10578     NULL, 0, sysctl_kmaps, "A",
10579     "Dump kernel address layout");
10580 
10581 
10582 void pagezero_simple(void *);
10583 void pagezero_cache(void *);
10584 void pagezero_mops(void *);
10585 
10586 DEFINE_IFUNC(static, void, pagezero, (void *))
10587 {
10588 	uint32_t dczid_el0;
10589 
10590 	dczid_el0 = READ_SPECIALREG(dczid_el0);
10591 
10592 	if (elf_hwcap2 & HWCAP2_MOPS)
10593 		return (pagezero_mops);
10594 	else if ((dczid_el0 & DCZID_DZP) == 0)
10595 		return (pagezero_cache);
10596 	else
10597 		return (pagezero_simple);
10598 }
10599