xref: /freebsd/sys/arm64/arm64/pmap.c (revision 2ee2ef607f6087757efd62b814cbf2400ef58ef2)
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 static int __read_frequently superpages_enabled = 1;
457 SYSCTL_INT(_vm_pmap, OID_AUTO, superpages_enabled,
458     CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &superpages_enabled, 0,
459     "Are large page mappings enabled?");
460 
461 /*
462  * True when Branch Target Identification should be used by userspace. This
463  * allows pmap to mark pages as guarded with ATTR_S1_GP.
464  */
465 __read_mostly static bool pmap_bti_support = false;
466 
467 /*
468  * Internal flags for pmap_enter()'s helper functions.
469  */
470 #define	PMAP_ENTER_NORECLAIM	0x1000000	/* Don't reclaim PV entries. */
471 #define	PMAP_ENTER_NOREPLACE	0x2000000	/* Don't replace mappings. */
472 
473 TAILQ_HEAD(pv_chunklist, pv_chunk);
474 
475 static void	free_pv_chunk(struct pv_chunk *pc);
476 static void	free_pv_chunk_batch(struct pv_chunklist *batch);
477 static void	free_pv_entry(pmap_t pmap, pv_entry_t pv);
478 static pv_entry_t get_pv_entry(pmap_t pmap, struct rwlock **lockp);
479 static vm_page_t reclaim_pv_chunk(pmap_t locked_pmap, struct rwlock **lockp);
480 static void	pmap_pvh_free(struct md_page *pvh, pmap_t pmap, vm_offset_t va);
481 static pv_entry_t pmap_pvh_remove(struct md_page *pvh, pmap_t pmap,
482 		    vm_offset_t va);
483 
484 static void pmap_abort_ptp(pmap_t pmap, vm_offset_t va, vm_page_t mpte);
485 static bool pmap_activate_int(struct thread *td, pmap_t pmap);
486 static void pmap_alloc_asid(pmap_t pmap);
487 static int pmap_change_props_locked(void *addr, vm_size_t size,
488     vm_prot_t prot, int mode, int old_mode, bool skip_unmapped);
489 static bool pmap_copy_l3c(pmap_t pmap, pt_entry_t *l3p, vm_offset_t va,
490     pt_entry_t l3e, vm_page_t ml3, struct rwlock **lockp);
491 static pt_entry_t *pmap_demote_l1(pmap_t pmap, pt_entry_t *l1, vm_offset_t va);
492 static pt_entry_t *pmap_demote_l2_locked(pmap_t pmap, pt_entry_t *l2,
493     vm_offset_t va, struct rwlock **lockp);
494 static pt_entry_t *pmap_demote_l2(pmap_t pmap, pt_entry_t *l2, vm_offset_t va);
495 static bool pmap_demote_l2c(pmap_t pmap, pt_entry_t *l2p, vm_offset_t va);
496 static bool pmap_demote_l3c(pmap_t pmap, pt_entry_t *l3p, vm_offset_t va);
497 static vm_page_t pmap_enter_quick_locked(pmap_t pmap, vm_offset_t va,
498     vm_page_t m, vm_prot_t prot, vm_page_t mpte, struct rwlock **lockp);
499 static int pmap_enter_l2(pmap_t pmap, vm_offset_t va, pd_entry_t new_l2,
500     u_int flags, vm_page_t m, struct rwlock **lockp);
501 static int pmap_enter_l3c(pmap_t pmap, vm_offset_t va, pt_entry_t l3e, u_int flags,
502     vm_page_t m, vm_page_t *ml3p, struct rwlock **lockp);
503 static bool pmap_every_pte_zero(vm_paddr_t pa);
504 static int pmap_insert_pt_page(pmap_t pmap, vm_page_t mpte, bool promoted,
505     bool all_l3e_AF_set);
506 static pt_entry_t pmap_load_l3c(pt_entry_t *l3p);
507 static void pmap_mask_set_l3c(pmap_t pmap, pt_entry_t *l3p, vm_offset_t va,
508     vm_offset_t *vap, vm_offset_t va_next, pt_entry_t mask, pt_entry_t nbits);
509 static bool pmap_pv_insert_l3c(pmap_t pmap, vm_offset_t va, vm_page_t m,
510     struct rwlock **lockp);
511 static void pmap_remove_kernel_l2(pmap_t pmap, pt_entry_t *l2, vm_offset_t va);
512 static int pmap_remove_l2(pmap_t pmap, pt_entry_t *l2, vm_offset_t sva,
513     pd_entry_t l1e, bool demote_kl2e, struct spglist *free,
514     struct rwlock **lockp);
515 static int pmap_remove_l3(pmap_t pmap, pt_entry_t *l3, vm_offset_t sva,
516     pd_entry_t l2e, struct spglist *free, struct rwlock **lockp);
517 static bool pmap_remove_l3c(pmap_t pmap, pt_entry_t *l3p, vm_offset_t va,
518     vm_offset_t *vap, vm_offset_t va_next, vm_page_t ml3, struct spglist *free,
519     struct rwlock **lockp);
520 static void pmap_reset_asid_set(pmap_t pmap);
521 static bool pmap_try_insert_pv_entry(pmap_t pmap, vm_offset_t va,
522     vm_page_t m, struct rwlock **lockp);
523 
524 static vm_page_t _pmap_alloc_l3(pmap_t pmap, vm_pindex_t ptepindex,
525 		struct rwlock **lockp);
526 
527 static void _pmap_unwire_l3(pmap_t pmap, vm_offset_t va, vm_page_t m,
528     struct spglist *free);
529 static int pmap_unuse_pt(pmap_t, vm_offset_t, pd_entry_t, struct spglist *);
530 static void pmap_update_entry(pmap_t pmap, pd_entry_t *pte, pd_entry_t newpte,
531     vm_offset_t va, vm_size_t size);
532 static __inline vm_page_t pmap_remove_pt_page(pmap_t pmap, vm_offset_t va);
533 
534 static uma_zone_t pmap_bti_ranges_zone;
535 static bool pmap_bti_same(pmap_t pmap, vm_offset_t sva, vm_offset_t eva,
536     pt_entry_t *pte);
537 static pt_entry_t pmap_pte_bti(pmap_t pmap, vm_offset_t va);
538 static void pmap_bti_on_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva);
539 static void *bti_dup_range(void *ctx, void *data);
540 static void bti_free_range(void *ctx, void *node);
541 static int pmap_bti_copy(pmap_t dst_pmap, pmap_t src_pmap);
542 static void pmap_bti_deassign_all(pmap_t pmap);
543 static void pagezero(void *);
544 
545 static void pmap_set_protected(pt_entry_t old_l3);
546 static void pmap_set_unprotected(pt_entry_t new_l3);
547 
548 /*
549  * These load the old table data and store the new value.
550  * They need to be atomic as the System MMU may write to the table at
551  * the same time as the CPU.
552  */
553 #define	pmap_clear(table)		atomic_store_64(table, 0)
554 #define	pmap_clear_bits(table, bits)	atomic_clear_64(table, bits)
555 #define	pmap_load(table)		(*table)
556 #define	pmap_load_clear(table)		atomic_swap_64(table, 0)
557 #define	pmap_load_store(table, entry)	atomic_swap_64(table, entry)
558 #define	pmap_set_bits(table, bits)	atomic_set_64(table, bits)
559 #define	pmap_store(table, entry)	atomic_store_64(table, entry)
560 
561 /********************/
562 /* Inline functions */
563 /********************/
564 
565 static __inline void
566 pagecopy(void *s, void *d)
567 {
568 
569 	memcpy(d, s, PAGE_SIZE);
570 }
571 
572 static __inline pd_entry_t *
573 pmap_l0(pmap_t pmap, vm_offset_t va)
574 {
575 
576 	return (&pmap->pm_l0[pmap_l0_index(va)]);
577 }
578 
579 static __inline pd_entry_t *
580 pmap_l0_to_l1(pd_entry_t *l0, vm_offset_t va)
581 {
582 	pd_entry_t *l1;
583 
584 	l1 = PHYS_TO_DMAP(PTE_TO_PHYS(pmap_load(l0)));
585 	return (&l1[pmap_l1_index(va)]);
586 }
587 
588 static __inline pd_entry_t *
589 pmap_l1(pmap_t pmap, vm_offset_t va)
590 {
591 	pd_entry_t *l0;
592 
593 	l0 = pmap_l0(pmap, va);
594 	if ((pmap_load(l0) & ATTR_DESCR_MASK) != L0_TABLE)
595 		return (NULL);
596 
597 	return (pmap_l0_to_l1(l0, va));
598 }
599 
600 static __inline pd_entry_t *
601 pmap_l1_to_l2(pd_entry_t *l1p, vm_offset_t va)
602 {
603 	pd_entry_t l1, *l2p;
604 
605 	l1 = pmap_load(l1p);
606 
607 	KASSERT(ADDR_IS_CANONICAL(va),
608 	    ("%s: Address not in canonical form: %lx", __func__, va));
609 	/*
610 	 * The valid bit may be clear if pmap_update_entry() is concurrently
611 	 * modifying the entry, so for KVA only the entry type may be checked.
612 	 */
613 	KASSERT(ADDR_IS_KERNEL(va) || (l1 & ATTR_DESCR_VALID) != 0,
614 	    ("%s: L1 entry %#lx for %#lx is invalid", __func__, l1, va));
615 	KASSERT((l1 & ATTR_DESCR_TYPE_MASK) == ATTR_DESCR_TYPE_TABLE,
616 	    ("%s: L1 entry %#lx for %#lx is a leaf", __func__, l1, va));
617 	l2p = PHYS_TO_DMAP(PTE_TO_PHYS(l1));
618 	return (&l2p[pmap_l2_index(va)]);
619 }
620 
621 static __inline pd_entry_t *
622 pmap_l2(pmap_t pmap, vm_offset_t va)
623 {
624 	pd_entry_t *l1;
625 
626 	l1 = pmap_l1(pmap, va);
627 	if ((pmap_load(l1) & ATTR_DESCR_MASK) != L1_TABLE)
628 		return (NULL);
629 
630 	return (pmap_l1_to_l2(l1, va));
631 }
632 
633 static __inline pt_entry_t *
634 pmap_l2_to_l3(pd_entry_t *l2p, vm_offset_t va)
635 {
636 	pd_entry_t l2;
637 	pt_entry_t *l3p;
638 
639 	l2 = pmap_load(l2p);
640 
641 	KASSERT(ADDR_IS_CANONICAL(va),
642 	    ("%s: Address not in canonical form: %lx", __func__, va));
643 	/*
644 	 * The valid bit may be clear if pmap_update_entry() is concurrently
645 	 * modifying the entry, so for KVA only the entry type may be checked.
646 	 */
647 	KASSERT(ADDR_IS_KERNEL(va) || (l2 & ATTR_DESCR_VALID) != 0,
648 	    ("%s: L2 entry %#lx for %#lx is invalid", __func__, l2, va));
649 	KASSERT((l2 & ATTR_DESCR_TYPE_MASK) == ATTR_DESCR_TYPE_TABLE,
650 	    ("%s: L2 entry %#lx for %#lx is a leaf", __func__, l2, va));
651 	l3p = PHYS_TO_DMAP(PTE_TO_PHYS(l2));
652 	return (&l3p[pmap_l3_index(va)]);
653 }
654 
655 /*
656  * Returns the lowest valid pde for a given virtual address.
657  * The next level may or may not point to a valid page or block.
658  */
659 static __inline pd_entry_t *
660 pmap_pde(pmap_t pmap, vm_offset_t va, int *level)
661 {
662 	pd_entry_t *l0, *l1, *l2, desc;
663 
664 	l0 = pmap_l0(pmap, va);
665 	desc = pmap_load(l0) & ATTR_DESCR_MASK;
666 	if (desc != L0_TABLE) {
667 		*level = -1;
668 		return (NULL);
669 	}
670 
671 	l1 = pmap_l0_to_l1(l0, va);
672 	desc = pmap_load(l1) & ATTR_DESCR_MASK;
673 	if (desc != L1_TABLE) {
674 		*level = 0;
675 		return (l0);
676 	}
677 
678 	l2 = pmap_l1_to_l2(l1, va);
679 	desc = pmap_load(l2) & ATTR_DESCR_MASK;
680 	if (desc != L2_TABLE) {
681 		*level = 1;
682 		return (l1);
683 	}
684 
685 	*level = 2;
686 	return (l2);
687 }
688 
689 /*
690  * Returns the lowest valid pte block or table entry for a given virtual
691  * address. If there are no valid entries return NULL and set the level to
692  * the first invalid level.
693  */
694 static __inline pt_entry_t *
695 pmap_pte(pmap_t pmap, vm_offset_t va, int *level)
696 {
697 	pd_entry_t *l1, *l2, desc;
698 	pt_entry_t *l3;
699 
700 	l1 = pmap_l1(pmap, va);
701 	if (l1 == NULL) {
702 		*level = 0;
703 		return (NULL);
704 	}
705 	desc = pmap_load(l1) & ATTR_DESCR_MASK;
706 	if (desc == L1_BLOCK) {
707 		PMAP_ASSERT_L1_BLOCKS_SUPPORTED;
708 		*level = 1;
709 		return (l1);
710 	}
711 
712 	if (desc != L1_TABLE) {
713 		*level = 1;
714 		return (NULL);
715 	}
716 
717 	l2 = pmap_l1_to_l2(l1, va);
718 	desc = pmap_load(l2) & ATTR_DESCR_MASK;
719 	if (desc == L2_BLOCK) {
720 		*level = 2;
721 		return (l2);
722 	}
723 
724 	if (desc != L2_TABLE) {
725 		*level = 2;
726 		return (NULL);
727 	}
728 
729 	*level = 3;
730 	l3 = pmap_l2_to_l3(l2, va);
731 	if ((pmap_load(l3) & ATTR_DESCR_MASK) != L3_PAGE)
732 		return (NULL);
733 
734 	return (l3);
735 }
736 
737 /*
738  * If the given pmap has an L{1,2}_BLOCK or L3_PAGE entry at the specified
739  * level that maps the specified virtual address, then a pointer to that entry
740  * is returned.  Otherwise, NULL is returned, unless INVARIANTS are enabled
741  * and a diagnostic message is provided, in which case this function panics.
742  */
743 static __always_inline pt_entry_t *
744 pmap_pte_exists(pmap_t pmap, vm_offset_t va, int level, const char *diag)
745 {
746 	pd_entry_t *l0p, *l1p, *l2p;
747 	pt_entry_t desc, *l3p;
748 	int walk_level __diagused;
749 
750 	KASSERT(level >= 0 && level < 4,
751 	    ("%s: %s passed an out-of-range level (%d)", __func__, diag,
752 	    level));
753 	l0p = pmap_l0(pmap, va);
754 	desc = pmap_load(l0p) & ATTR_DESCR_MASK;
755 	if (desc == L0_TABLE && level > 0) {
756 		l1p = pmap_l0_to_l1(l0p, va);
757 		desc = pmap_load(l1p) & ATTR_DESCR_MASK;
758 		if (desc == L1_BLOCK && level == 1) {
759 			PMAP_ASSERT_L1_BLOCKS_SUPPORTED;
760 			return (l1p);
761 		}
762 		if (desc == L1_TABLE && level > 1) {
763 			l2p = pmap_l1_to_l2(l1p, va);
764 			desc = pmap_load(l2p) & ATTR_DESCR_MASK;
765 			if (desc == L2_BLOCK && level == 2)
766 				return (l2p);
767 			else if (desc == L2_TABLE && level > 2) {
768 				l3p = pmap_l2_to_l3(l2p, va);
769 				desc = pmap_load(l3p) & ATTR_DESCR_MASK;
770 				if (desc == L3_PAGE && level == 3)
771 					return (l3p);
772 				else
773 					walk_level = 3;
774 			} else
775 				walk_level = 2;
776 		} else
777 			walk_level = 1;
778 	} else
779 		walk_level = 0;
780 	KASSERT(diag == NULL,
781 	    ("%s: va %#lx not mapped at level %d, desc %ld at level %d",
782 	    diag, va, level, desc, walk_level));
783 	return (NULL);
784 }
785 
786 bool
787 pmap_ps_enabled(pmap_t pmap)
788 {
789 	/*
790 	 * Promotion requires a hypervisor call when the kernel is running
791 	 * in EL1. To stop this disable superpage support on non-stage 1
792 	 * pmaps for now.
793 	 */
794 	if (pmap->pm_stage != PM_STAGE1)
795 		return (false);
796 
797 #ifdef KMSAN
798 	/*
799 	 * The break-before-make in pmap_update_entry() results in a situation
800 	 * where a CPU may call into the KMSAN runtime while the entry is
801 	 * invalid.  If the entry is used to map the current thread structure,
802 	 * then the runtime will attempt to access unmapped memory.  Avoid this
803 	 * by simply disabling superpage promotion for the kernel map.
804 	 */
805 	if (pmap == kernel_pmap)
806 		return (false);
807 #endif
808 
809 	return (superpages_enabled != 0);
810 }
811 
812 bool
813 pmap_vs_enabled(void)
814 {
815 	/*
816 	 * 8 and 16 are the only values hardware can support, but allow for the
817 	 * possibility of artificially restricting the bits, e.g. for testing.
818 	 */
819 	KASSERT(vmids.asid_bits <= 16, ("VMID bits %d > 16", vmids.asid_bits));
820 	return (vmids.asid_bits > 8);
821 }
822 
823 bool
824 pmap_get_tables(pmap_t pmap, vm_offset_t va, pd_entry_t **l0, pd_entry_t **l1,
825     pd_entry_t **l2, pt_entry_t **l3)
826 {
827 	pd_entry_t *l0p, *l1p, *l2p;
828 
829 	if (pmap->pm_l0 == NULL)
830 		return (false);
831 
832 	l0p = pmap_l0(pmap, va);
833 	*l0 = l0p;
834 
835 	if ((pmap_load(l0p) & ATTR_DESCR_MASK) != L0_TABLE)
836 		return (false);
837 
838 	l1p = pmap_l0_to_l1(l0p, va);
839 	*l1 = l1p;
840 
841 	if ((pmap_load(l1p) & ATTR_DESCR_MASK) == L1_BLOCK) {
842 		PMAP_ASSERT_L1_BLOCKS_SUPPORTED;
843 		*l2 = NULL;
844 		*l3 = NULL;
845 		return (true);
846 	}
847 
848 	if ((pmap_load(l1p) & ATTR_DESCR_MASK) != L1_TABLE)
849 		return (false);
850 
851 	l2p = pmap_l1_to_l2(l1p, va);
852 	*l2 = l2p;
853 
854 	if ((pmap_load(l2p) & ATTR_DESCR_MASK) == L2_BLOCK) {
855 		*l3 = NULL;
856 		return (true);
857 	}
858 
859 	if ((pmap_load(l2p) & ATTR_DESCR_MASK) != L2_TABLE)
860 		return (false);
861 
862 	*l3 = pmap_l2_to_l3(l2p, va);
863 
864 	return (true);
865 }
866 
867 static __inline int
868 pmap_l3_valid(pt_entry_t l3)
869 {
870 
871 	return ((l3 & ATTR_DESCR_MASK) == L3_PAGE);
872 }
873 
874 CTASSERT(L1_BLOCK == L2_BLOCK);
875 
876 static pt_entry_t
877 pmap_pte_memattr(pmap_t pmap, vm_memattr_t memattr)
878 {
879 	pt_entry_t val;
880 
881 	if (pmap->pm_stage == PM_STAGE1) {
882 		val = ATTR_S1_IDX(memattr);
883 		if (memattr == VM_MEMATTR_DEVICE)
884 			val |= ATTR_S1_XN;
885 		return (val);
886 	}
887 
888 	val = 0;
889 
890 	switch (memattr) {
891 	case VM_MEMATTR_DEVICE:
892 		return (ATTR_S2_MEMATTR(ATTR_S2_MEMATTR_DEVICE_nGnRnE) |
893 		    ATTR_S2_XN(ATTR_S2_XN_ALL));
894 	case VM_MEMATTR_UNCACHEABLE:
895 		return (ATTR_S2_MEMATTR(ATTR_S2_MEMATTR_NC));
896 	case VM_MEMATTR_WRITE_BACK:
897 		return (ATTR_S2_MEMATTR(ATTR_S2_MEMATTR_WB));
898 	case VM_MEMATTR_WRITE_THROUGH:
899 		return (ATTR_S2_MEMATTR(ATTR_S2_MEMATTR_WT));
900 	default:
901 		panic("%s: invalid memory attribute %x", __func__, memattr);
902 	}
903 }
904 
905 static pt_entry_t
906 pmap_pte_prot(pmap_t pmap, vm_prot_t prot)
907 {
908 	pt_entry_t val;
909 
910 	val = 0;
911 	if (pmap->pm_stage == PM_STAGE1) {
912 		if ((prot & VM_PROT_EXECUTE) == 0)
913 			val |= ATTR_S1_XN;
914 		if ((prot & VM_PROT_WRITE) == 0)
915 			val |= ATTR_S1_AP(ATTR_S1_AP_RO);
916 	} else {
917 		if ((prot & VM_PROT_WRITE) != 0)
918 			val |= ATTR_S2_S2AP(ATTR_S2_S2AP_WRITE);
919 		if ((prot & VM_PROT_READ) != 0)
920 			val |= ATTR_S2_S2AP(ATTR_S2_S2AP_READ);
921 		if ((prot & VM_PROT_EXECUTE) == 0)
922 			val |= ATTR_S2_XN(ATTR_S2_XN_ALL);
923 	}
924 
925 	return (val);
926 }
927 
928 /*
929  * Checks if the PTE is dirty.
930  */
931 static inline int
932 pmap_pte_dirty(pmap_t pmap, pt_entry_t pte)
933 {
934 
935 	KASSERT((pte & ATTR_SW_MANAGED) != 0, ("pte %#lx is unmanaged", pte));
936 
937 	if (pmap->pm_stage == PM_STAGE1) {
938 		KASSERT((pte & (ATTR_S1_AP_RW_BIT | ATTR_SW_DBM)) != 0,
939 		    ("pte %#lx is writeable and missing ATTR_SW_DBM", pte));
940 
941 		return ((pte & (ATTR_S1_AP_RW_BIT | ATTR_SW_DBM)) ==
942 		    (ATTR_S1_AP(ATTR_S1_AP_RW) | ATTR_SW_DBM));
943 	}
944 
945 	return ((pte & ATTR_S2_S2AP(ATTR_S2_S2AP_WRITE)) ==
946 	    ATTR_S2_S2AP(ATTR_S2_S2AP_WRITE));
947 }
948 
949 static __inline void
950 pmap_resident_count_inc(pmap_t pmap, int count)
951 {
952 
953 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
954 	pmap->pm_stats.resident_count += count;
955 }
956 
957 static __inline void
958 pmap_resident_count_dec(pmap_t pmap, int count)
959 {
960 
961 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
962 	KASSERT(pmap->pm_stats.resident_count >= count,
963 	    ("pmap %p resident count underflow %ld %d", pmap,
964 	    pmap->pm_stats.resident_count, count));
965 	pmap->pm_stats.resident_count -= count;
966 }
967 
968 static vm_paddr_t
969 pmap_early_vtophys(vm_offset_t va)
970 {
971 	vm_paddr_t pa_page;
972 
973 	pa_page = arm64_address_translate_s1e1r(va) & PAR_PA_MASK;
974 	return (pa_page | (va & PAR_LOW_MASK));
975 }
976 
977 /* State of the bootstrapped DMAP page tables */
978 struct pmap_bootstrap_state {
979 	pt_entry_t	*l1;
980 	pt_entry_t	*l2;
981 	pt_entry_t	*l3;
982 	vm_offset_t	freemempos;
983 	vm_offset_t	va;
984 	vm_paddr_t	pa;
985 	pt_entry_t	table_attrs;
986 	u_int		l0_slot;
987 	u_int		l1_slot;
988 	u_int		l2_slot;
989 	bool		dmap_valid;
990 };
991 
992 /* The bootstrap state */
993 static struct pmap_bootstrap_state bs_state = {
994 	.l1 = NULL,
995 	.l2 = NULL,
996 	.l3 = NULL,
997 	.table_attrs = TATTR_PXN_TABLE,
998 	.l0_slot = L0_ENTRIES,
999 	.l1_slot = Ln_ENTRIES,
1000 	.l2_slot = Ln_ENTRIES,
1001 	.dmap_valid = false,
1002 };
1003 
1004 static void
1005 pmap_bootstrap_l0_table(struct pmap_bootstrap_state *state)
1006 {
1007 	vm_paddr_t l1_pa;
1008 	pd_entry_t l0e;
1009 	u_int l0_slot;
1010 
1011 	/* Link the level 0 table to a level 1 table */
1012 	l0_slot = pmap_l0_index(state->va);
1013 	if (l0_slot != state->l0_slot) {
1014 		/*
1015 		 * Make sure we move from a low address to high address
1016 		 * before the DMAP region is ready. This ensures we never
1017 		 * modify an existing mapping until we can map from a
1018 		 * physical address to a virtual address.
1019 		 */
1020 		MPASS(state->l0_slot < l0_slot ||
1021 		    state->l0_slot == L0_ENTRIES ||
1022 		    state->dmap_valid);
1023 
1024 		/* Reset lower levels */
1025 		state->l2 = NULL;
1026 		state->l3 = NULL;
1027 		state->l1_slot = Ln_ENTRIES;
1028 		state->l2_slot = Ln_ENTRIES;
1029 
1030 		/* Check the existing L0 entry */
1031 		state->l0_slot = l0_slot;
1032 		if (state->dmap_valid) {
1033 			l0e = pagetable_l0_ttbr1[l0_slot];
1034 			if ((l0e & ATTR_DESCR_VALID) != 0) {
1035 				MPASS((l0e & ATTR_DESCR_MASK) == L0_TABLE);
1036 				l1_pa = PTE_TO_PHYS(l0e);
1037 				state->l1 = PHYS_TO_DMAP(l1_pa);
1038 				return;
1039 			}
1040 		}
1041 
1042 		/* Create a new L0 table entry */
1043 		state->l1 = (pt_entry_t *)state->freemempos;
1044 		memset_early(state->l1, 0, PAGE_SIZE);
1045 		state->freemempos += PAGE_SIZE;
1046 
1047 		l1_pa = pmap_early_vtophys((vm_offset_t)state->l1);
1048 		MPASS((l1_pa & Ln_TABLE_MASK) == 0);
1049 		MPASS(pagetable_l0_ttbr1[l0_slot] == 0);
1050 		pmap_store(&pagetable_l0_ttbr1[l0_slot], PHYS_TO_PTE(l1_pa) |
1051 		    TATTR_UXN_TABLE | TATTR_AP_TABLE_NO_EL0 | L0_TABLE);
1052 	}
1053 	KASSERT(state->l1 != NULL, ("%s: NULL l1", __func__));
1054 }
1055 
1056 static void
1057 pmap_bootstrap_l1_table(struct pmap_bootstrap_state *state)
1058 {
1059 	vm_paddr_t l2_pa;
1060 	pd_entry_t l1e;
1061 	u_int l1_slot;
1062 
1063 	/* Make sure there is a valid L0 -> L1 table */
1064 	pmap_bootstrap_l0_table(state);
1065 
1066 	/* Link the level 1 table to a level 2 table */
1067 	l1_slot = pmap_l1_index(state->va);
1068 	if (l1_slot != state->l1_slot) {
1069 		/* See pmap_bootstrap_l0_table for a description */
1070 		MPASS(state->l1_slot < l1_slot ||
1071 		    state->l1_slot == Ln_ENTRIES ||
1072 		    state->dmap_valid);
1073 
1074 		/* Reset lower levels */
1075 		state->l3 = NULL;
1076 		state->l2_slot = Ln_ENTRIES;
1077 
1078 		/* Check the existing L1 entry */
1079 		state->l1_slot = l1_slot;
1080 		if (state->dmap_valid) {
1081 			l1e = state->l1[l1_slot];
1082 			if ((l1e & ATTR_DESCR_VALID) != 0) {
1083 				MPASS((l1e & ATTR_DESCR_MASK) == L1_TABLE);
1084 				l2_pa = PTE_TO_PHYS(l1e);
1085 				state->l2 = PHYS_TO_DMAP(l2_pa);
1086 				return;
1087 			}
1088 		}
1089 
1090 		/* Create a new L1 table entry */
1091 		state->l2 = (pt_entry_t *)state->freemempos;
1092 		memset_early(state->l2, 0, PAGE_SIZE);
1093 		state->freemempos += PAGE_SIZE;
1094 
1095 		l2_pa = pmap_early_vtophys((vm_offset_t)state->l2);
1096 		MPASS((l2_pa & Ln_TABLE_MASK) == 0);
1097 		MPASS(state->l1[l1_slot] == 0);
1098 		pmap_store(&state->l1[l1_slot], PHYS_TO_PTE(l2_pa) |
1099 		    state->table_attrs | L1_TABLE);
1100 	}
1101 	KASSERT(state->l2 != NULL, ("%s: NULL l2", __func__));
1102 }
1103 
1104 static void
1105 pmap_bootstrap_l2_table(struct pmap_bootstrap_state *state)
1106 {
1107 	vm_paddr_t l3_pa;
1108 	pd_entry_t l2e;
1109 	u_int l2_slot;
1110 
1111 	/* Make sure there is a valid L1 -> L2 table */
1112 	pmap_bootstrap_l1_table(state);
1113 
1114 	/* Link the level 2 table to a level 3 table */
1115 	l2_slot = pmap_l2_index(state->va);
1116 	if (l2_slot != state->l2_slot) {
1117 		/* See pmap_bootstrap_l0_table for a description */
1118 		MPASS(state->l2_slot < l2_slot ||
1119 		    state->l2_slot == Ln_ENTRIES ||
1120 		    state->dmap_valid);
1121 
1122 		/* Check the existing L2 entry */
1123 		state->l2_slot = l2_slot;
1124 		if (state->dmap_valid) {
1125 			l2e = state->l2[l2_slot];
1126 			if ((l2e & ATTR_DESCR_VALID) != 0) {
1127 				MPASS((l2e & ATTR_DESCR_MASK) == L2_TABLE);
1128 				l3_pa = PTE_TO_PHYS(l2e);
1129 				state->l3 = PHYS_TO_DMAP(l3_pa);
1130 				return;
1131 			}
1132 		}
1133 
1134 		/* Create a new L2 table entry */
1135 		state->l3 = (pt_entry_t *)state->freemempos;
1136 		memset_early(state->l3, 0, PAGE_SIZE);
1137 		state->freemempos += PAGE_SIZE;
1138 
1139 		l3_pa = pmap_early_vtophys((vm_offset_t)state->l3);
1140 		MPASS((l3_pa & Ln_TABLE_MASK) == 0);
1141 		MPASS(state->l2[l2_slot] == 0);
1142 		pmap_store(&state->l2[l2_slot], PHYS_TO_PTE(l3_pa) |
1143 		    state->table_attrs | L2_TABLE);
1144 	}
1145 	KASSERT(state->l3 != NULL, ("%s: NULL l3", __func__));
1146 }
1147 
1148 static void
1149 pmap_bootstrap_l2_block(struct pmap_bootstrap_state *state, int i)
1150 {
1151 	pt_entry_t contig;
1152 	u_int l2_slot;
1153 	bool first;
1154 
1155 	if ((physmap[i + 1] - state->pa) < L2_SIZE)
1156 		return;
1157 
1158 	/* Make sure there is a valid L1 table */
1159 	pmap_bootstrap_l1_table(state);
1160 
1161 	MPASS((state->va & L2_OFFSET) == 0);
1162 	for (first = true, contig = 0;
1163 	    state->va < DMAP_MAX_ADDRESS &&
1164 	    (physmap[i + 1] - state->pa) >= L2_SIZE;
1165 	    state->va += L2_SIZE, state->pa += L2_SIZE) {
1166 		/*
1167 		 * Stop if we are about to walk off the end of what the
1168 		 * current L1 slot can address.
1169 		 */
1170 		if (!first && (state->pa & L1_OFFSET) == 0)
1171 			break;
1172 
1173 		/*
1174 		 * If we have an aligned, contiguous chunk of L2C_ENTRIES
1175 		 * L2 blocks, set the contiguous bit within each PTE so that
1176 		 * the chunk can be cached using only one TLB entry.
1177 		 */
1178 		if ((state->pa & L2C_OFFSET) == 0) {
1179 			if (state->va + L2C_SIZE < DMAP_MAX_ADDRESS &&
1180 			    physmap[i + 1] - state->pa >= L2C_SIZE) {
1181 				contig = ATTR_CONTIGUOUS;
1182 			} else {
1183 				contig = 0;
1184 			}
1185 		}
1186 
1187 		first = false;
1188 		l2_slot = pmap_l2_index(state->va);
1189 		MPASS((state->pa & L2_OFFSET) == 0);
1190 		MPASS(state->l2[l2_slot] == 0);
1191 		pmap_store(&state->l2[l2_slot], PHYS_TO_PTE(state->pa) |
1192 		    ATTR_AF | pmap_sh_attr | ATTR_S1_XN | ATTR_KERN_GP |
1193 		    ATTR_S1_IDX(VM_MEMATTR_WRITE_BACK) | contig | L2_BLOCK);
1194 	}
1195 	MPASS(state->va == (state->pa - dmap_phys_base + DMAP_MIN_ADDRESS));
1196 }
1197 
1198 static void
1199 pmap_bootstrap_l3_page(struct pmap_bootstrap_state *state, int i)
1200 {
1201 	pt_entry_t contig;
1202 	u_int l3_slot;
1203 	bool first;
1204 
1205 	if (physmap[i + 1] - state->pa < L3_SIZE)
1206 		return;
1207 
1208 	/* Make sure there is a valid L2 table */
1209 	pmap_bootstrap_l2_table(state);
1210 
1211 	MPASS((state->va & L3_OFFSET) == 0);
1212 	for (first = true, contig = 0;
1213 	    state->va < DMAP_MAX_ADDRESS &&
1214 	    physmap[i + 1] - state->pa >= L3_SIZE;
1215 	    state->va += L3_SIZE, state->pa += L3_SIZE) {
1216 		/*
1217 		 * Stop if we are about to walk off the end of what the
1218 		 * current L2 slot can address.
1219 		 */
1220 		if (!first && (state->pa & L2_OFFSET) == 0)
1221 			break;
1222 
1223 		/*
1224 		 * If we have an aligned, contiguous chunk of L3C_ENTRIES
1225 		 * L3 pages, set the contiguous bit within each PTE so that
1226 		 * the chunk can be cached using only one TLB entry.
1227 		 */
1228 		if ((state->pa & L3C_OFFSET) == 0) {
1229 			if (state->va + L3C_SIZE < DMAP_MAX_ADDRESS &&
1230 			    physmap[i + 1] - state->pa >= L3C_SIZE) {
1231 				contig = ATTR_CONTIGUOUS;
1232 			} else {
1233 				contig = 0;
1234 			}
1235 		}
1236 
1237 		first = false;
1238 		l3_slot = pmap_l3_index(state->va);
1239 		MPASS((state->pa & L3_OFFSET) == 0);
1240 		MPASS(state->l3[l3_slot] == 0);
1241 		pmap_store(&state->l3[l3_slot], PHYS_TO_PTE(state->pa) |
1242 		    ATTR_AF | pmap_sh_attr | ATTR_S1_XN | ATTR_KERN_GP |
1243 		    ATTR_S1_IDX(VM_MEMATTR_WRITE_BACK) | contig | L3_PAGE);
1244 	}
1245 	MPASS(state->va == (state->pa - dmap_phys_base + DMAP_MIN_ADDRESS));
1246 }
1247 
1248 void
1249 pmap_bootstrap_dmap(vm_size_t kernlen)
1250 {
1251 	vm_paddr_t start_pa, pa;
1252 	uint64_t tcr;
1253 	int i;
1254 
1255 	tcr = READ_SPECIALREG(tcr_el1);
1256 
1257 	/* Verify that the ASID is set through TTBR0. */
1258 	KASSERT((tcr & TCR_A1) == 0, ("pmap_bootstrap: TCR_EL1.A1 != 0"));
1259 
1260 	if ((tcr & TCR_DS) != 0)
1261 		pmap_lpa_enabled = true;
1262 
1263 	pmap_l1_supported = L1_BLOCKS_SUPPORTED;
1264 
1265 	start_pa = pmap_early_vtophys(KERNBASE);
1266 
1267 	bs_state.freemempos = KERNBASE + kernlen;
1268 	bs_state.freemempos = roundup2(bs_state.freemempos, PAGE_SIZE);
1269 
1270 	/* Fill in physmap array. */
1271 	physmap_idx = physmem_avail(physmap, nitems(physmap));
1272 
1273 	dmap_phys_base = physmap[0] & ~L1_OFFSET;
1274 	dmap_phys_max = 0;
1275 	dmap_max_addr = 0;
1276 
1277 	for (i = 0; i < physmap_idx; i += 2) {
1278 		bs_state.pa = physmap[i] & ~L3_OFFSET;
1279 		bs_state.va = bs_state.pa - dmap_phys_base + DMAP_MIN_ADDRESS;
1280 
1281 		/* Create L3 mappings at the start of the region */
1282 		if ((bs_state.pa & L2_OFFSET) != 0)
1283 			pmap_bootstrap_l3_page(&bs_state, i);
1284 		MPASS(bs_state.pa <= physmap[i + 1]);
1285 
1286 		if (L1_BLOCKS_SUPPORTED) {
1287 			/* Create L2 mappings at the start of the region */
1288 			if ((bs_state.pa & L1_OFFSET) != 0)
1289 				pmap_bootstrap_l2_block(&bs_state, i);
1290 			MPASS(bs_state.pa <= physmap[i + 1]);
1291 
1292 			/* Create the main L1 block mappings */
1293 			for (; bs_state.va < DMAP_MAX_ADDRESS &&
1294 			    (physmap[i + 1] - bs_state.pa) >= L1_SIZE;
1295 			    bs_state.va += L1_SIZE, bs_state.pa += L1_SIZE) {
1296 				/* Make sure there is a valid L1 table */
1297 				pmap_bootstrap_l0_table(&bs_state);
1298 				MPASS((bs_state.pa & L1_OFFSET) == 0);
1299 				pmap_store(
1300 				    &bs_state.l1[pmap_l1_index(bs_state.va)],
1301 				    PHYS_TO_PTE(bs_state.pa) | ATTR_AF |
1302 				    pmap_sh_attr |
1303 				    ATTR_S1_IDX(VM_MEMATTR_WRITE_BACK) |
1304 				    ATTR_S1_XN | ATTR_KERN_GP | L1_BLOCK);
1305 			}
1306 			MPASS(bs_state.pa <= physmap[i + 1]);
1307 
1308 			/* Create L2 mappings at the end of the region */
1309 			pmap_bootstrap_l2_block(&bs_state, i);
1310 		} else {
1311 			while (bs_state.va < DMAP_MAX_ADDRESS &&
1312 			    (physmap[i + 1] - bs_state.pa) >= L2_SIZE) {
1313 				pmap_bootstrap_l2_block(&bs_state, i);
1314 			}
1315 		}
1316 		MPASS(bs_state.pa <= physmap[i + 1]);
1317 
1318 		/* Create L3 mappings at the end of the region */
1319 		pmap_bootstrap_l3_page(&bs_state, i);
1320 		MPASS(bs_state.pa == physmap[i + 1]);
1321 
1322 		if (bs_state.pa > dmap_phys_max) {
1323 			dmap_phys_max = bs_state.pa;
1324 			dmap_max_addr = bs_state.va;
1325 		}
1326 	}
1327 
1328 	pmap_s1_invalidate_all_kernel();
1329 
1330 	bs_state.dmap_valid = true;
1331 
1332 	/* Exclude the kernel and DMAP region */
1333 	pa = pmap_early_vtophys(bs_state.freemempos);
1334 	physmem_exclude_region(start_pa, pa - start_pa, EXFLAG_NOALLOC);
1335 }
1336 
1337 static void
1338 pmap_bootstrap_l2(vm_offset_t va)
1339 {
1340 	KASSERT((va & L1_OFFSET) == 0, ("Invalid virtual address"));
1341 
1342 	/* Leave bs_state.pa as it's only needed to bootstrap blocks and pages*/
1343 	bs_state.va = va;
1344 
1345 	for (; bs_state.va < VM_MAX_KERNEL_ADDRESS; bs_state.va += L1_SIZE)
1346 		pmap_bootstrap_l1_table(&bs_state);
1347 }
1348 
1349 static void
1350 pmap_bootstrap_l3(vm_offset_t va)
1351 {
1352 	KASSERT((va & L2_OFFSET) == 0, ("Invalid virtual address"));
1353 
1354 	/* Leave bs_state.pa as it's only needed to bootstrap blocks and pages*/
1355 	bs_state.va = va;
1356 
1357 	for (; bs_state.va < VM_MAX_KERNEL_ADDRESS; bs_state.va += L2_SIZE)
1358 		pmap_bootstrap_l2_table(&bs_state);
1359 }
1360 
1361 /*
1362  *	Bootstrap the system enough to run with virtual memory.
1363  */
1364 void
1365 pmap_bootstrap(void)
1366 {
1367 	vm_offset_t dpcpu, msgbufpv;
1368 	vm_paddr_t start_pa, pa;
1369 	size_t largest_phys_size;
1370 
1371 	/* Set this early so we can use the pagetable walking functions */
1372 	kernel_pmap_store.pm_l0 = pagetable_l0_ttbr1;
1373 	mtx_init(&kernel_pmap->pm_mtx, "kernel pmap", NULL, MTX_DEF);
1374 	kernel_pmap->pm_l0_paddr =
1375 	    pmap_early_vtophys((vm_offset_t)kernel_pmap_store.pm_l0);
1376 	TAILQ_INIT(&kernel_pmap->pm_pvchunk);
1377 	vm_radix_init(&kernel_pmap->pm_root);
1378 	kernel_pmap->pm_cookie = COOKIE_FROM(-1, INT_MIN);
1379 	kernel_pmap->pm_stage = PM_STAGE1;
1380 	kernel_pmap->pm_levels = 4;
1381 	kernel_pmap->pm_ttbr = kernel_pmap->pm_l0_paddr;
1382 	kernel_pmap->pm_asid_set = &asids;
1383 
1384 	/* Reserve some VA space for early BIOS/ACPI mapping */
1385 	preinit_map_va = roundup2(bs_state.freemempos, L2_SIZE);
1386 
1387 	virtual_avail = preinit_map_va + PMAP_PREINIT_MAPPING_SIZE;
1388 	virtual_avail = roundup2(virtual_avail, L1_SIZE);
1389 	virtual_end = VM_MAX_KERNEL_ADDRESS - PMAP_MAPDEV_EARLY_SIZE - L2_SIZE;
1390 	kernel_vm_end = virtual_avail;
1391 
1392 	/*
1393 	 * We only use PXN when we know nothing will be executed from it, e.g.
1394 	 * the DMAP region.
1395 	 */
1396 	bs_state.table_attrs &= ~TATTR_PXN_TABLE;
1397 
1398 	/*
1399 	 * Find the physical memory we could use. This needs to be after we
1400 	 * exclude any memory that is mapped into the DMAP region but should
1401 	 * not be used by the kernel, e.g. some UEFI memory types.
1402 	 */
1403 	physmap_idx = physmem_avail(physmap, nitems(physmap));
1404 
1405 	/*
1406 	 * Find space for early allocations. We search for the largest
1407 	 * region. This is because the user may choose a large msgbuf.
1408 	 * This could be smarter, e.g. to allow multiple regions to be
1409 	 * used & switch to the next when one is full.
1410 	 */
1411 	largest_phys_size = 0;
1412 	for (int i = 0; i < physmap_idx; i += 2) {
1413 		if ((physmap[i + 1] - physmap[i]) > largest_phys_size) {
1414 			largest_phys_size = physmap[i + 1] - physmap[i];
1415 			bs_state.freemempos = PHYS_TO_DMAP_ADDR(physmap[i]);
1416 		}
1417 	}
1418 
1419 	start_pa = pmap_early_vtophys(bs_state.freemempos);
1420 
1421 	/*
1422 	 * Create the l2 tables up to VM_MAX_KERNEL_ADDRESS.  We assume that the
1423 	 * loader allocated the first and only l2 page table page used to map
1424 	 * the kernel, preloaded files and module metadata.
1425 	 */
1426 	pmap_bootstrap_l2(KERNBASE + L1_SIZE);
1427 	/* And the l3 tables for the early devmap */
1428 	pmap_bootstrap_l3(VM_MAX_KERNEL_ADDRESS - (PMAP_MAPDEV_EARLY_SIZE));
1429 
1430 	pmap_s1_invalidate_all_kernel();
1431 
1432 #define alloc_pages(var, np)						\
1433 	(var) = bs_state.freemempos;					\
1434 	bs_state.freemempos += (np * PAGE_SIZE);			\
1435 	memset_early((char *)(var), 0, ((np) * PAGE_SIZE));
1436 
1437 	/* Allocate dynamic per-cpu area. */
1438 	alloc_pages(dpcpu, DPCPU_SIZE / PAGE_SIZE);
1439 	dpcpu_init((void *)dpcpu, 0);
1440 
1441 	/* Allocate memory for the msgbuf, e.g. for /sbin/dmesg */
1442 	alloc_pages(msgbufpv, round_page(msgbufsize) / PAGE_SIZE);
1443 	msgbufp = (void *)msgbufpv;
1444 
1445 	/* Allocate space for the CPU0 CMAP */
1446 	bs_state.va = virtual_end;
1447 	pmap_bootstrap_l2_table(&bs_state);
1448 	pmap_store(&bs_state.l3[pmap_l3_index(bs_state.va)],
1449 	    PHYS_TO_PTE(pmap_early_vtophys((vm_offset_t)bs_state.l3)) |
1450 	    ATTR_AF | pmap_sh_attr | ATTR_S1_XN | ATTR_KERN_GP |
1451 	    ATTR_S1_IDX(VM_MEMATTR_WRITE_BACK) | L3_PAGE);
1452 	dsb(ishst);
1453 
1454 	mtx_init(&cmap_lock, "SYSMAPS", NULL, MTX_DEF);
1455 	cmap1_addr = (void *)(virtual_end + L3_SIZE);
1456 	cmap1_pte = &bs_state.l3[pmap_l3_index((vm_offset_t)cmap1_addr)];
1457 
1458 	pa = pmap_early_vtophys(bs_state.freemempos);
1459 
1460 	physmem_exclude_region(start_pa, pa - start_pa, EXFLAG_NOALLOC);
1461 }
1462 
1463 #if defined(KASAN) || defined(KMSAN)
1464 static void
1465 pmap_bootstrap_allocate_san_l2(vm_paddr_t start_pa, vm_paddr_t end_pa,
1466     vm_offset_t *vap, vm_offset_t eva)
1467 {
1468 	vm_paddr_t pa;
1469 	vm_offset_t va;
1470 	pd_entry_t *l2;
1471 
1472 	va = *vap;
1473 	pa = rounddown2(end_pa - L2_SIZE, L2_SIZE);
1474 	for (; pa >= start_pa && va < eva; va += L2_SIZE, pa -= L2_SIZE) {
1475 		l2 = pmap_l2(kernel_pmap, va);
1476 
1477 		/*
1478 		 * KASAN stack checking results in us having already allocated
1479 		 * part of our shadow map, so we can just skip those segments.
1480 		 */
1481 		if ((pmap_load(l2) & ATTR_DESCR_VALID) != 0) {
1482 			pa += L2_SIZE;
1483 			continue;
1484 		}
1485 
1486 		bzero_early(PHYS_TO_DMAP(pa), L2_SIZE);
1487 		physmem_exclude_region(pa, L2_SIZE, EXFLAG_NOALLOC);
1488 		pmap_store(l2, PHYS_TO_PTE(pa) | PMAP_SAN_PTE_BITS | L2_BLOCK);
1489 	}
1490 	*vap = va;
1491 }
1492 
1493 /*
1494  * Finish constructing the initial shadow map:
1495  * - Count how many pages from KERNBASE to virtual_avail (scaled for
1496  *   shadow map)
1497  * - Map that entire range using L2 superpages.
1498  */
1499 static void
1500 pmap_bootstrap_san1(vm_offset_t va, int scale)
1501 {
1502 	vm_offset_t eva;
1503 	vm_paddr_t kernstart;
1504 	int i;
1505 
1506 	kernstart = pmap_early_vtophys(KERNBASE);
1507 
1508 	/*
1509 	 * Rebuild physmap one more time, we may have excluded more regions from
1510 	 * allocation since pmap_bootstrap().
1511 	 */
1512 	physmap_idx = physmem_avail(physmap, nitems(physmap));
1513 
1514 	eva = va + (virtual_avail - VM_MIN_KERNEL_ADDRESS) / scale;
1515 
1516 	/*
1517 	 * Find a slot in the physmap large enough for what we needed.  We try to put
1518 	 * the shadow map as high up as we can to avoid depleting the lower 4GB in case
1519 	 * it's needed for, e.g., an xhci controller that can only do 32-bit DMA.
1520 	 */
1521 	for (i = physmap_idx - 2; i >= 0; i -= 2) {
1522 		vm_paddr_t plow, phigh;
1523 
1524 		/* L2 mappings must be backed by memory that is L2-aligned */
1525 		plow = roundup2(physmap[i], L2_SIZE);
1526 		phigh = physmap[i + 1];
1527 		if (plow >= phigh)
1528 			continue;
1529 		if (kernstart >= plow && kernstart < phigh)
1530 			phigh = kernstart;
1531 		if (phigh - plow >= L2_SIZE) {
1532 			pmap_bootstrap_allocate_san_l2(plow, phigh, &va, eva);
1533 			if (va >= eva)
1534 				break;
1535 		}
1536 	}
1537 	if (i < 0)
1538 		panic("Could not find phys region for shadow map");
1539 
1540 	/*
1541 	 * Done. We should now have a valid shadow address mapped for all KVA
1542 	 * that has been mapped so far, i.e., KERNBASE to virtual_avail. Thus,
1543 	 * shadow accesses by the sanitizer runtime will succeed for this range.
1544 	 * When the kernel virtual address range is later expanded, as will
1545 	 * happen in vm_mem_init(), the shadow map will be grown as well. This
1546 	 * is handled by pmap_san_enter().
1547 	 */
1548 }
1549 
1550 void
1551 pmap_bootstrap_san(void)
1552 {
1553 #ifdef KASAN
1554 	pmap_bootstrap_san1(KASAN_MIN_ADDRESS, KASAN_SHADOW_SCALE);
1555 #else
1556 	static uint8_t kmsan_shad_ptp[PAGE_SIZE * 2] __aligned(PAGE_SIZE);
1557 	static uint8_t kmsan_orig_ptp[PAGE_SIZE * 2] __aligned(PAGE_SIZE);
1558 	pd_entry_t *l0, *l1;
1559 
1560 	if (virtual_avail - VM_MIN_KERNEL_ADDRESS > L1_SIZE)
1561 		panic("initial kernel map is too large");
1562 
1563 	l0 = pmap_l0(kernel_pmap, KMSAN_SHAD_MIN_ADDRESS);
1564 	pmap_store(l0, L0_TABLE | PHYS_TO_PTE(
1565 	    pmap_early_vtophys((vm_offset_t)kmsan_shad_ptp)));
1566 	l1 = pmap_l0_to_l1(l0, KMSAN_SHAD_MIN_ADDRESS);
1567 	pmap_store(l1, L1_TABLE | PHYS_TO_PTE(
1568 	    pmap_early_vtophys((vm_offset_t)kmsan_shad_ptp + PAGE_SIZE)));
1569 	pmap_bootstrap_san1(KMSAN_SHAD_MIN_ADDRESS, 1);
1570 
1571 	l0 = pmap_l0(kernel_pmap, KMSAN_ORIG_MIN_ADDRESS);
1572 	pmap_store(l0, L0_TABLE | PHYS_TO_PTE(
1573 	    pmap_early_vtophys((vm_offset_t)kmsan_orig_ptp)));
1574 	l1 = pmap_l0_to_l1(l0, KMSAN_ORIG_MIN_ADDRESS);
1575 	pmap_store(l1, L1_TABLE | PHYS_TO_PTE(
1576 	    pmap_early_vtophys((vm_offset_t)kmsan_orig_ptp + PAGE_SIZE)));
1577 	pmap_bootstrap_san1(KMSAN_ORIG_MIN_ADDRESS, 1);
1578 #endif
1579 }
1580 #endif
1581 
1582 /*
1583  *	Initialize a vm_page's machine-dependent fields.
1584  */
1585 void
1586 pmap_page_init(vm_page_t m)
1587 {
1588 
1589 	TAILQ_INIT(&m->md.pv_list);
1590 	m->md.pv_memattr = VM_MEMATTR_WRITE_BACK;
1591 	m->md.pv_flags = 0;
1592 }
1593 
1594 static void
1595 pmap_init_asids(struct asid_set *set, int bits)
1596 {
1597 	int i;
1598 
1599 	set->asid_bits = bits;
1600 
1601 	/*
1602 	 * We may be too early in the overall initialization process to use
1603 	 * bit_alloc().
1604 	 */
1605 	set->asid_set_size = 1 << set->asid_bits;
1606 	set->asid_set = kmem_malloc(bitstr_size(set->asid_set_size),
1607 	    M_WAITOK | M_ZERO);
1608 	for (i = 0; i < ASID_FIRST_AVAILABLE; i++)
1609 		bit_set(set->asid_set, i);
1610 	set->asid_next = ASID_FIRST_AVAILABLE;
1611 	mtx_init(&set->asid_set_mutex, "asid set", NULL, MTX_SPIN);
1612 }
1613 
1614 static void
1615 pmap_init_pv_table(void)
1616 {
1617 	struct vm_phys_seg *seg, *next_seg;
1618 	struct pmap_large_md_page *pvd;
1619 	vm_size_t s;
1620 	int domain, i, j, pages;
1621 
1622 	/*
1623 	 * We depend on the size being evenly divisible into a page so
1624 	 * that the pv_table array can be indexed directly while
1625 	 * safely spanning multiple pages from different domains.
1626 	 */
1627 	CTASSERT(PAGE_SIZE % sizeof(*pvd) == 0);
1628 
1629 	/*
1630 	 * Calculate the size of the array.
1631 	 */
1632 	s = 0;
1633 	for (i = 0; i < vm_phys_nsegs; i++) {
1634 		seg = &vm_phys_segs[i];
1635 		pages = pmap_l2_pindex(roundup2(seg->end, L2_SIZE)) -
1636 		    pmap_l2_pindex(seg->start);
1637 		s += round_page(pages * sizeof(*pvd));
1638 	}
1639 	pv_table = kva_alloc(s);
1640 	if (pv_table == NULL)
1641 		panic("%s: kva_alloc failed\n", __func__);
1642 
1643 	/*
1644 	 * Iterate physical segments to allocate domain-local memory for PV
1645 	 * list headers.
1646 	 */
1647 	pvd = pv_table;
1648 	for (i = 0; i < vm_phys_nsegs; i++) {
1649 		seg = &vm_phys_segs[i];
1650 		pages = pmap_l2_pindex(roundup2(seg->end, L2_SIZE)) -
1651 		    pmap_l2_pindex(seg->start);
1652 		domain = seg->domain;
1653 
1654 		s = round_page(pages * sizeof(*pvd));
1655 
1656 		for (j = 0; j < s; j += PAGE_SIZE) {
1657 			vm_page_t m = vm_page_alloc_noobj_domain(domain,
1658 			    VM_ALLOC_ZERO);
1659 			if (m == NULL)
1660 				panic("failed to allocate PV table page");
1661 			pmap_qenter((char *)pvd + j, &m, 1);
1662 		}
1663 
1664 		for (j = 0; j < s / sizeof(*pvd); j++) {
1665 			rw_init_flags(&pvd->pv_lock, "pmap pv list", RW_NEW);
1666 			TAILQ_INIT(&pvd->pv_page.pv_list);
1667 			pvd++;
1668 		}
1669 	}
1670 	pvd = &pv_dummy_large;
1671 	memset(pvd, 0, sizeof(*pvd));
1672 	rw_init_flags(&pvd->pv_lock, "pmap pv list dummy", RW_NEW);
1673 	TAILQ_INIT(&pvd->pv_page.pv_list);
1674 
1675 	/*
1676 	 * Set pointers from vm_phys_segs to pv_table.
1677 	 */
1678 	for (i = 0, pvd = pv_table; i < vm_phys_nsegs; i++) {
1679 		seg = &vm_phys_segs[i];
1680 		seg->md_first = pvd;
1681 		pvd += pmap_l2_pindex(roundup2(seg->end, L2_SIZE)) -
1682 		    pmap_l2_pindex(seg->start);
1683 
1684 		/*
1685 		 * If there is a following segment, and the final
1686 		 * superpage of this segment and the initial superpage
1687 		 * of the next segment are the same then adjust the
1688 		 * pv_table entry for that next segment down by one so
1689 		 * that the pv_table entries will be shared.
1690 		 */
1691 		if (i + 1 < vm_phys_nsegs) {
1692 			next_seg = &vm_phys_segs[i + 1];
1693 			if (pmap_l2_pindex(roundup2(seg->end, L2_SIZE)) - 1 ==
1694 			    pmap_l2_pindex(next_seg->start)) {
1695 				pvd--;
1696 			}
1697 		}
1698 	}
1699 }
1700 
1701 static cpu_feat_en
1702 pmap_dbm_check(const struct cpu_feat *feat __unused, u_int midr __unused)
1703 {
1704 	uint64_t id_aa64mmfr1;
1705 
1706 	id_aa64mmfr1 = READ_SPECIALREG(id_aa64mmfr1_el1);
1707 	if (ID_AA64MMFR1_HAFDBS_VAL(id_aa64mmfr1) >=
1708 	    ID_AA64MMFR1_HAFDBS_AF_DBS)
1709 		return (FEAT_DEFAULT_ENABLE);
1710 
1711 	return (FEAT_ALWAYS_DISABLE);
1712 }
1713 
1714 static bool
1715 pmap_dbm_has_errata(const struct cpu_feat *feat __unused, u_int midr,
1716     u_int **errata_list, u_int *errata_count)
1717 {
1718 	/* Disable on Cortex-A55 for erratum 1024718 - all revisions */
1719 	if (CPU_IMPL(midr) == CPU_IMPL_ARM &&
1720 	    CPU_PART(midr) == CPU_PART_CORTEX_A55) {
1721 		static u_int errata_id = 1024718;
1722 
1723 		*errata_list = &errata_id;
1724 		*errata_count = 1;
1725 		return (true);
1726 	}
1727 
1728 	/* Disable on Cortex-A510 for erratum 2051678 - r0p0 to r0p2 */
1729 	if (midr_check_var_part_range(midr, CPU_IMPL_ARM, CPU_PART_CORTEX_A510,
1730 	    0, 0, 0, 2)) {
1731 		static u_int errata_id = 2051678;
1732 
1733 		*errata_list = &errata_id;
1734 		*errata_count = 1;
1735 		return (true);
1736 	}
1737 
1738 	return (false);
1739 }
1740 
1741 static bool
1742 pmap_dbm_enable(const struct cpu_feat *feat __unused,
1743     cpu_feat_errata errata_status, u_int *errata_list __unused,
1744     u_int errata_count)
1745 {
1746 	uint64_t tcr;
1747 
1748 	/* Skip if there is an erratum affecting DBM */
1749 	if (errata_status != ERRATA_NONE)
1750 		return (false);
1751 
1752 	tcr = READ_SPECIALREG(tcr_el1) | TCR_HD;
1753 	WRITE_SPECIALREG(tcr_el1, tcr);
1754 	isb();
1755 	/* Flush the local TLB for the TCR_HD flag change */
1756 	dsb(nshst);
1757 	__asm __volatile("tlbi vmalle1");
1758 	dsb(nsh);
1759 	isb();
1760 
1761 	return (true);
1762 }
1763 
1764 CPU_FEAT(feat_hafdbs, "Hardware management of the Access flag and dirty state",
1765     pmap_dbm_check, pmap_dbm_has_errata, pmap_dbm_enable, NULL,
1766     CPU_FEAT_AFTER_DEV | CPU_FEAT_PER_CPU);
1767 
1768 static cpu_feat_en
1769 pmap_multiple_tlbi_check(const struct cpu_feat *feat __unused, u_int midr)
1770 {
1771 	/*
1772 	 * ARM C1-Premium erratum 4193780
1773 	 * ARM C1-Ultra erratum 4193780
1774 	 * ARM Cortex-A76 erratum 4193800
1775 	 * ARM Cortex-A76AE erratum 4193801
1776 	 * ARM Cortex-A77 erratum 4193798
1777 	 * ARM Cortex-A78 erratum 4193791
1778 	 * ARM Cortex-A78AE erratum 4193793
1779 	 * ARM Cortex-A78C erratum 4193794
1780 	 * ARM Cortex-A710 erratum 4193788
1781 	 * ARM Cortex-X1 erratum 4193791
1782 	 * ARM Cortex-X1C erratum 4193792
1783 	 * ARM Cortex-X2 erratum 4193788
1784 	 * ARM Cortex-X3 erratum 4193786
1785 	 * ARM Cortex-X4 erratum 4118414
1786 	 * ARM Cortex-X925 erratum 4193781
1787 	 * ARM Neoverse-N1 erratum 4193800
1788 	 * ARM Neoverse-N2 erratum 4193789
1789 	 * ARM Neoverse-V1 erratum 4193790
1790 	 * ARM Neoverse-V2 erratum 4193787
1791 	 * ARM Neoverse-V3 erratum 4193784
1792 	 * ARM Neoverse-V3AE erratum 4193784
1793 	 * Present in all revisions
1794 	 */
1795 	if (CPU_IMPL(midr) == CPU_IMPL_ARM) {
1796 		switch(CPU_PART(midr)) {
1797 		case CPU_PART_C1_PREMIUM:
1798 		case CPU_PART_C1_ULTRA:
1799 		case CPU_PART_CORTEX_A76:
1800 		case CPU_PART_CORTEX_A76AE:
1801 		case CPU_PART_CORTEX_A77:
1802 		case CPU_PART_CORTEX_A78:
1803 		case CPU_PART_CORTEX_A78AE:
1804 		case CPU_PART_CORTEX_A78C:
1805 		case CPU_PART_CORTEX_A710:
1806 		case CPU_PART_CORTEX_X1:
1807 		case CPU_PART_CORTEX_X1C:
1808 		case CPU_PART_CORTEX_X2:
1809 		case CPU_PART_CORTEX_X3:
1810 		case CPU_PART_CORTEX_X4:
1811 		case CPU_PART_CORTEX_X925:
1812 		case CPU_PART_NEOVERSE_N1:
1813 		case CPU_PART_NEOVERSE_N2:
1814 		case CPU_PART_NEOVERSE_V1:
1815 		case CPU_PART_NEOVERSE_V2:
1816 		case CPU_PART_NEOVERSE_V3:
1817 		case CPU_PART_NEOVERSE_V3AE:
1818 			return (FEAT_DEFAULT_ENABLE);
1819 		}
1820 	}
1821 
1822 	/*
1823 	 * Cortex-A55 erratum 2441007 (Cat B rare)
1824 	 * Present in all revisions
1825 	 */
1826 	if (CPU_IMPL(midr) == CPU_IMPL_ARM &&
1827 	    CPU_PART(midr) == CPU_PART_CORTEX_A55)
1828 		return (FEAT_DEFAULT_DISABLE);
1829 
1830 	/*
1831 	 * Cortex-A510 erratum 2441009 (Cat B rare)
1832 	 * Present in r0p0 - r1p1
1833 	 * Fixed in r1p2
1834 	 */
1835 	if (midr_check_var_part_range(midr, CPU_IMPL_ARM, CPU_PART_CORTEX_A510,
1836 	    0, 0, 1, 1))
1837 		return (FEAT_DEFAULT_DISABLE);
1838 
1839 	return (FEAT_ALWAYS_DISABLE);
1840 }
1841 
1842 static bool
1843 pmap_multiple_tlbi_enable(const struct cpu_feat *feat __unused,
1844     cpu_feat_errata errata_status, u_int *errata_list __unused,
1845     u_int errata_count __unused)
1846 {
1847 	pmap_multiple_tlbi = true;
1848 	return (true);
1849 }
1850 
1851 CPU_FEAT(errata_multi_tlbi, "Multiple TLBI errata",
1852     pmap_multiple_tlbi_check, NULL, pmap_multiple_tlbi_enable, NULL,
1853     CPU_FEAT_EARLY_BOOT | CPU_FEAT_PER_CPU);
1854 
1855 /*
1856  *	Initialize the pmap module.
1857  *
1858  *	Called by vm_mem_init(), to initialize any structures that the pmap
1859  *	system needs to map virtual memory.
1860  */
1861 void
1862 pmap_init(void)
1863 {
1864 	uint64_t mmfr1;
1865 	int i, vmid_bits;
1866 
1867 	/*
1868 	 * Are large page mappings enabled?
1869 	 */
1870 	TUNABLE_INT_FETCH("vm.pmap.superpages_enabled", &superpages_enabled);
1871 	if (superpages_enabled) {
1872 		KASSERT(MAXPAGESIZES > 1 && pagesizes[1] == 0,
1873 		    ("pmap_init: can't assign to pagesizes[1]"));
1874 		pagesizes[1] = L3C_SIZE;
1875 		KASSERT(MAXPAGESIZES > 2 && pagesizes[2] == 0,
1876 		    ("pmap_init: can't assign to pagesizes[2]"));
1877 		pagesizes[2] = L2_SIZE;
1878 		if (L1_BLOCKS_SUPPORTED) {
1879 			KASSERT(MAXPAGESIZES > 3 && pagesizes[3] == 0,
1880 			    ("pmap_init: can't assign to pagesizes[3]"));
1881 			pagesizes[3] = L1_SIZE;
1882 		}
1883 	}
1884 
1885 	/*
1886 	 * Initialize the ASID allocator.
1887 	 */
1888 	pmap_init_asids(&asids,
1889 	    (READ_SPECIALREG(tcr_el1) & TCR_ASID_16) != 0 ? 16 : 8);
1890 
1891 	if (has_hyp()) {
1892 		mmfr1 = READ_SPECIALREG(id_aa64mmfr1_el1);
1893 		vmid_bits = 8;
1894 
1895 		if (ID_AA64MMFR1_VMIDBits_VAL(mmfr1) ==
1896 		    ID_AA64MMFR1_VMIDBits_16)
1897 			vmid_bits = 16;
1898 		pmap_init_asids(&vmids, vmid_bits);
1899 	}
1900 
1901 	/*
1902 	 * Initialize pv chunk lists.
1903 	 */
1904 	for (i = 0; i < PMAP_MEMDOM; i++) {
1905 		mtx_init(&pv_chunks[i].pvc_lock, "pmap pv chunk list", NULL,
1906 		    MTX_DEF);
1907 		TAILQ_INIT(&pv_chunks[i].pvc_list);
1908 	}
1909 	pmap_init_pv_table();
1910 
1911 	vm_initialized = 1;
1912 }
1913 
1914 static SYSCTL_NODE(_vm_pmap, OID_AUTO, l1, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
1915     "L1 (1GB/64GB) page mapping counters");
1916 
1917 static COUNTER_U64_DEFINE_EARLY(pmap_l1_demotions);
1918 SYSCTL_COUNTER_U64(_vm_pmap_l1, OID_AUTO, demotions, CTLFLAG_RD,
1919     &pmap_l1_demotions, "L1 (1GB/64GB) page demotions");
1920 
1921 SYSCTL_BOOL(_vm_pmap_l1, OID_AUTO, supported, CTLFLAG_RD, &pmap_l1_supported,
1922     0, "L1 blocks are supported");
1923 
1924 static SYSCTL_NODE(_vm_pmap, OID_AUTO, l2c, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
1925     "L2C (32MB/1GB) page mapping counters");
1926 
1927 static COUNTER_U64_DEFINE_EARLY(pmap_l2c_demotions);
1928 SYSCTL_COUNTER_U64(_vm_pmap_l2c, OID_AUTO, demotions, CTLFLAG_RD,
1929     &pmap_l2c_demotions, "L2C (32MB/1GB) page demotions");
1930 
1931 static SYSCTL_NODE(_vm_pmap, OID_AUTO, l2, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
1932     "2MB page mapping counters");
1933 
1934 static COUNTER_U64_DEFINE_EARLY(pmap_l2_demotions);
1935 SYSCTL_COUNTER_U64(_vm_pmap_l2, OID_AUTO, demotions, CTLFLAG_RD,
1936     &pmap_l2_demotions, "L2 (2MB/32MB) page demotions");
1937 
1938 static COUNTER_U64_DEFINE_EARLY(pmap_l2_mappings);
1939 SYSCTL_COUNTER_U64(_vm_pmap_l2, OID_AUTO, mappings, CTLFLAG_RD,
1940     &pmap_l2_mappings, "L2 (2MB/32MB) page mappings");
1941 
1942 static COUNTER_U64_DEFINE_EARLY(pmap_l2_p_failures);
1943 SYSCTL_COUNTER_U64(_vm_pmap_l2, OID_AUTO, p_failures, CTLFLAG_RD,
1944     &pmap_l2_p_failures, "L2 (2MB/32MB) page promotion failures");
1945 
1946 static COUNTER_U64_DEFINE_EARLY(pmap_l2_promotions);
1947 SYSCTL_COUNTER_U64(_vm_pmap_l2, OID_AUTO, promotions, CTLFLAG_RD,
1948     &pmap_l2_promotions, "L2 (2MB/32MB) page promotions");
1949 
1950 static SYSCTL_NODE(_vm_pmap, OID_AUTO, l3c, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
1951     "L3C (64KB/2MB) page mapping counters");
1952 
1953 static COUNTER_U64_DEFINE_EARLY(pmap_l3c_demotions);
1954 SYSCTL_COUNTER_U64(_vm_pmap_l3c, OID_AUTO, demotions, CTLFLAG_RD,
1955     &pmap_l3c_demotions, "L3C (64KB/2MB) page demotions");
1956 
1957 static COUNTER_U64_DEFINE_EARLY(pmap_l3c_mappings);
1958 SYSCTL_COUNTER_U64(_vm_pmap_l3c, OID_AUTO, mappings, CTLFLAG_RD,
1959     &pmap_l3c_mappings, "L3C (64KB/2MB) page mappings");
1960 
1961 static COUNTER_U64_DEFINE_EARLY(pmap_l3c_p_failures);
1962 SYSCTL_COUNTER_U64(_vm_pmap_l3c, OID_AUTO, p_failures, CTLFLAG_RD,
1963     &pmap_l3c_p_failures, "L3C (64KB/2MB) page promotion failures");
1964 
1965 static COUNTER_U64_DEFINE_EARLY(pmap_l3c_promotions);
1966 SYSCTL_COUNTER_U64(_vm_pmap_l3c, OID_AUTO, promotions, CTLFLAG_RD,
1967     &pmap_l3c_promotions, "L3C (64KB/2MB) page promotions");
1968 
1969 /*
1970  * If the given value for "final_only" is false, then any cached intermediate-
1971  * level entries, i.e., L{0,1,2}_TABLE entries, are invalidated in addition to
1972  * any cached final-level entry, i.e., either an L{1,2}_BLOCK or L3_PAGE entry.
1973  * Otherwise, just the cached final-level entry is invalidated.
1974  */
1975 static __inline void
1976 pmap_s1_invalidate_kernel(uint64_t r, bool final_only)
1977 {
1978 	if (final_only)
1979 		__asm __volatile("tlbi vaale1is, %0" : : "r" (r));
1980 	else
1981 		__asm __volatile("tlbi vaae1is, %0" : : "r" (r));
1982 }
1983 
1984 static __inline void
1985 pmap_s1_invalidate_user(uint64_t r, bool final_only)
1986 {
1987 	if (final_only)
1988 		__asm __volatile("tlbi vale1is, %0" : : "r" (r));
1989 	else
1990 		__asm __volatile("tlbi vae1is, %0" : : "r" (r));
1991 }
1992 
1993 /*
1994  * Invalidates any cached final- and optionally intermediate-level TLB entries
1995  * for the specified virtual address in the given virtual address space.
1996  */
1997 static __inline void
1998 pmap_s1_invalidate_page(pmap_t pmap, vm_offset_t va, bool final_only)
1999 {
2000 	uint64_t r;
2001 
2002 	PMAP_ASSERT_STAGE1(pmap);
2003 
2004 	dsb(ishst);
2005 	r = TLBI_VA(va);
2006 	if (pmap == kernel_pmap) {
2007 		pmap_s1_invalidate_kernel(r, final_only);
2008 	} else {
2009 		r |= ASID_TO_OPERAND(COOKIE_TO_ASID(pmap->pm_cookie));
2010 		pmap_s1_invalidate_user(r, final_only);
2011 	}
2012 	if (pmap_multiple_tlbi) {
2013 		dsb(ish);
2014 		__asm __volatile("tlbi	vale1is, xzr" ::: "memory");
2015 	}
2016 	dsb(ish);
2017 	isb();
2018 }
2019 
2020 static __inline void
2021 pmap_s2_invalidate_page(pmap_t pmap, vm_offset_t va, bool final_only)
2022 {
2023 	PMAP_ASSERT_STAGE2(pmap);
2024 	MPASS(pmap_stage2_invalidate_range != NULL);
2025 	pmap_stage2_invalidate_range(pmap_to_ttbr0(pmap), va, va + PAGE_SIZE,
2026 	    final_only);
2027 }
2028 
2029 static __inline void
2030 pmap_invalidate_page(pmap_t pmap, vm_offset_t va, bool final_only)
2031 {
2032 	if (pmap->pm_stage == PM_STAGE1)
2033 		pmap_s1_invalidate_page(pmap, va, final_only);
2034 	else
2035 		pmap_s2_invalidate_page(pmap, va, final_only);
2036 }
2037 
2038 /*
2039  * Use stride L{1,2}_SIZE when invalidating the TLB entries for L{1,2}_BLOCK
2040  * mappings.  Otherwise, use stride L3_SIZE.
2041  */
2042 static __inline void
2043 pmap_s1_invalidate_strided(pmap_t pmap, vm_offset_t sva, vm_offset_t eva,
2044     vm_offset_t stride, bool final_only)
2045 {
2046 	uint64_t end, r, start;
2047 
2048 	PMAP_ASSERT_STAGE1(pmap);
2049 
2050 	dsb(ishst);
2051 	if (pmap == kernel_pmap) {
2052 		start = TLBI_VA(sva);
2053 		end = TLBI_VA(eva);
2054 		for (r = start; r < end; r += TLBI_VA(stride))
2055 			pmap_s1_invalidate_kernel(r, final_only);
2056 	} else {
2057 		start = end = ASID_TO_OPERAND(COOKIE_TO_ASID(pmap->pm_cookie));
2058 		start |= TLBI_VA(sva);
2059 		end |= TLBI_VA(eva);
2060 		for (r = start; r < end; r += TLBI_VA(stride))
2061 			pmap_s1_invalidate_user(r, final_only);
2062 	}
2063 	if (pmap_multiple_tlbi) {
2064 		dsb(ish);
2065 		__asm __volatile("tlbi	vale1is, xzr" ::: "memory");
2066 	}
2067 	dsb(ish);
2068 	isb();
2069 }
2070 
2071 /*
2072  * Invalidates any cached final- and optionally intermediate-level TLB entries
2073  * for the specified virtual address range in the given virtual address space.
2074  */
2075 static __inline void
2076 pmap_s1_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva,
2077     bool final_only)
2078 {
2079 	pmap_s1_invalidate_strided(pmap, sva, eva, L3_SIZE, final_only);
2080 }
2081 
2082 static __inline void
2083 pmap_s2_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva,
2084     bool final_only)
2085 {
2086 	PMAP_ASSERT_STAGE2(pmap);
2087 	MPASS(pmap_stage2_invalidate_range != NULL);
2088 	pmap_stage2_invalidate_range(pmap_to_ttbr0(pmap), sva, eva, final_only);
2089 }
2090 
2091 static __inline void
2092 pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva,
2093     bool final_only)
2094 {
2095 	if (pmap->pm_stage == PM_STAGE1)
2096 		pmap_s1_invalidate_range(pmap, sva, eva, final_only);
2097 	else
2098 		pmap_s2_invalidate_range(pmap, sva, eva, final_only);
2099 }
2100 
2101 void
2102 pmap_s1_invalidate_all_kernel(void)
2103 {
2104 	dsb(ishst);
2105 	__asm __volatile("tlbi vmalle1is");
2106 	if (pmap_multiple_tlbi) {
2107 		dsb(ish);
2108 		__asm __volatile("tlbi	vale1is, xzr" ::: "memory");
2109 	}
2110 	dsb(ish);
2111 	isb();
2112 }
2113 
2114 /*
2115  * Invalidates all cached intermediate- and final-level TLB entries for the
2116  * given virtual address space.
2117  */
2118 static __inline void
2119 pmap_s1_invalidate_all(pmap_t pmap)
2120 {
2121 	uint64_t r;
2122 
2123 	PMAP_ASSERT_STAGE1(pmap);
2124 
2125 	dsb(ishst);
2126 	if (pmap == kernel_pmap) {
2127 		__asm __volatile("tlbi vmalle1is");
2128 	} else {
2129 		r = ASID_TO_OPERAND(COOKIE_TO_ASID(pmap->pm_cookie));
2130 		__asm __volatile("tlbi aside1is, %0" : : "r" (r));
2131 	}
2132 	if (pmap_multiple_tlbi) {
2133 		dsb(ish);
2134 		__asm __volatile("tlbi	vale1is, xzr" ::: "memory");
2135 	}
2136 	dsb(ish);
2137 	isb();
2138 }
2139 
2140 static __inline void
2141 pmap_s2_invalidate_all(pmap_t pmap)
2142 {
2143 	PMAP_ASSERT_STAGE2(pmap);
2144 	MPASS(pmap_stage2_invalidate_all != NULL);
2145 	pmap_stage2_invalidate_all(pmap_to_ttbr0(pmap));
2146 }
2147 
2148 static __inline void
2149 pmap_invalidate_all(pmap_t pmap)
2150 {
2151 	if (pmap->pm_stage == PM_STAGE1)
2152 		pmap_s1_invalidate_all(pmap);
2153 	else
2154 		pmap_s2_invalidate_all(pmap);
2155 }
2156 
2157 /*
2158  *	Routine:	pmap_extract
2159  *	Function:
2160  *		Extract the physical page address associated
2161  *		with the given map/virtual_address pair.
2162  */
2163 vm_paddr_t
2164 pmap_extract(pmap_t pmap, vm_offset_t va)
2165 {
2166 	pt_entry_t *pte, tpte;
2167 	vm_paddr_t pa;
2168 	int lvl;
2169 
2170 	pa = 0;
2171 	PMAP_LOCK(pmap);
2172 	/*
2173 	 * Find the block or page map for this virtual address. pmap_pte
2174 	 * will return either a valid block/page entry, or NULL.
2175 	 */
2176 	pte = pmap_pte(pmap, va, &lvl);
2177 	if (pte != NULL) {
2178 		tpte = pmap_load(pte);
2179 		pa = PTE_TO_PHYS(tpte);
2180 		switch(lvl) {
2181 		case 1:
2182 			PMAP_ASSERT_L1_BLOCKS_SUPPORTED;
2183 			KASSERT((tpte & ATTR_DESCR_MASK) == L1_BLOCK,
2184 			    ("pmap_extract: Invalid L1 pte found: %lx",
2185 			    tpte & ATTR_DESCR_MASK));
2186 			pa |= (va & L1_OFFSET);
2187 			break;
2188 		case 2:
2189 			KASSERT((tpte & ATTR_DESCR_MASK) == L2_BLOCK,
2190 			    ("pmap_extract: Invalid L2 pte found: %lx",
2191 			    tpte & ATTR_DESCR_MASK));
2192 			pa |= (va & L2_OFFSET);
2193 			break;
2194 		case 3:
2195 			KASSERT((tpte & ATTR_DESCR_MASK) == L3_PAGE,
2196 			    ("pmap_extract: Invalid L3 pte found: %lx",
2197 			    tpte & ATTR_DESCR_MASK));
2198 			pa |= (va & L3_OFFSET);
2199 			break;
2200 		}
2201 	}
2202 	PMAP_UNLOCK(pmap);
2203 	return (pa);
2204 }
2205 
2206 /*
2207  *	Routine:	pmap_extract_and_hold
2208  *	Function:
2209  *		Atomically extract and hold the physical page
2210  *		with the given pmap and virtual address pair
2211  *		if that mapping permits the given protection.
2212  */
2213 vm_page_t
2214 pmap_extract_and_hold(pmap_t pmap, vm_offset_t va, vm_prot_t prot)
2215 {
2216 	pt_entry_t *pte, tpte;
2217 	vm_offset_t off;
2218 	vm_page_t m;
2219 	int lvl;
2220 	bool use;
2221 
2222 	m = NULL;
2223 	PMAP_LOCK(pmap);
2224 	pte = pmap_pte(pmap, va, &lvl);
2225 	if (pte != NULL) {
2226 		tpte = pmap_load(pte);
2227 
2228 		KASSERT(lvl > 0 && lvl <= 3,
2229 		    ("pmap_extract_and_hold: Invalid level %d", lvl));
2230 		/*
2231 		 * Check that the pte is either a L3 page, or a L1 or L2 block
2232 		 * entry. We can assume L1_BLOCK == L2_BLOCK.
2233 		 */
2234 		KASSERT((lvl == 3 && (tpte & ATTR_DESCR_MASK) == L3_PAGE) ||
2235 		    (lvl < 3 && (tpte & ATTR_DESCR_MASK) == L1_BLOCK),
2236 		    ("pmap_extract_and_hold: Invalid pte at L%d: %lx", lvl,
2237 		     tpte & ATTR_DESCR_MASK));
2238 
2239 		use = false;
2240 		if ((prot & VM_PROT_WRITE) == 0)
2241 			use = true;
2242 		else if (pmap->pm_stage == PM_STAGE1 &&
2243 		    (tpte & ATTR_S1_AP_RW_BIT) == ATTR_S1_AP(ATTR_S1_AP_RW))
2244 			use = true;
2245 		else if (pmap->pm_stage == PM_STAGE2 &&
2246 		    ((tpte & ATTR_S2_S2AP(ATTR_S2_S2AP_WRITE)) ==
2247 		     ATTR_S2_S2AP(ATTR_S2_S2AP_WRITE)))
2248 			use = true;
2249 
2250 		if (use) {
2251 			switch (lvl) {
2252 			case 1:
2253 				off = va & L1_OFFSET;
2254 				break;
2255 			case 2:
2256 				off = va & L2_OFFSET;
2257 				break;
2258 			case 3:
2259 			default:
2260 				off = 0;
2261 			}
2262 			m = PHYS_TO_VM_PAGE(PTE_TO_PHYS(tpte) | off);
2263 			if (m != NULL && !vm_page_wire_mapped(m))
2264 				m = NULL;
2265 		}
2266 	}
2267 	PMAP_UNLOCK(pmap);
2268 	return (m);
2269 }
2270 
2271 /*
2272  * Returns true if the entire kernel virtual address range is mapped
2273  */
2274 static bool
2275 pmap_kmapped_range(void *va, vm_size_t size)
2276 {
2277 	pt_entry_t *pte, tpte;
2278 	vm_offset_t eva, sva;
2279 
2280 	sva = (vm_offset_t)va;
2281 	KASSERT(sva >= VM_MIN_KERNEL_ADDRESS,
2282 	    ("%s: Invalid virtual address: %lx", __func__, sva));
2283 	MPASS(size != 0);
2284 	eva = sva + size - 1;
2285 	KASSERT(eva > sva, ("%s: Size too large: sva %lx, size %lx", __func__,
2286 	    sva, size));
2287 
2288 	while (sva <= eva) {
2289 		pte = pmap_l1(kernel_pmap, sva);
2290 		if (pte == NULL)
2291 			return (false);
2292 		tpte = pmap_load(pte);
2293 		if (tpte == 0)
2294 			return (false);
2295 		if ((tpte & ATTR_DESCR_TYPE_MASK) == ATTR_DESCR_TYPE_BLOCK) {
2296 			sva = (sva & ~L1_OFFSET) + L1_SIZE;
2297 			continue;
2298 		}
2299 
2300 		pte = pmap_l1_to_l2(&tpte, sva);
2301 		tpte = pmap_load(pte);
2302 		if (tpte == 0)
2303 			return (false);
2304 		if ((tpte & ATTR_DESCR_TYPE_MASK) == ATTR_DESCR_TYPE_BLOCK) {
2305 			sva = (sva & ~L2_OFFSET) + L2_SIZE;
2306 			continue;
2307 		}
2308 		pte = pmap_l2_to_l3(&tpte, sva);
2309 		tpte = pmap_load(pte);
2310 		if (tpte == 0)
2311 			return (false);
2312 		MPASS((tpte & ATTR_DESCR_TYPE_MASK) == ATTR_DESCR_TYPE_PAGE);
2313 		if ((tpte & ATTR_CONTIGUOUS) == ATTR_CONTIGUOUS)
2314 			sva = (sva & ~L3C_OFFSET) + L3C_SIZE;
2315 		else
2316 			sva = (sva & ~L3_OFFSET) + L3_SIZE;
2317 	}
2318 
2319 	return (true);
2320 }
2321 
2322 /*
2323  * Walks the page tables to translate a kernel virtual address to a
2324  * physical address. Returns true if the kva is valid and stores the
2325  * physical address in pa if it is not NULL.
2326  *
2327  * See the comment above data_abort() for the rationale for specifying
2328  * NO_PERTHREAD_SSP here.
2329  */
2330 bool NO_PERTHREAD_SSP
2331 pmap_klookup(vm_offset_t va, vm_paddr_t *pa)
2332 {
2333 	pt_entry_t *pte, tpte;
2334 	register_t intr;
2335 	uint64_t par;
2336 
2337 	/*
2338 	 * Disable interrupts so we don't get interrupted between asking
2339 	 * for address translation, and getting the result back.
2340 	 */
2341 	intr = intr_disable();
2342 	par = arm64_address_translate_s1e1r(va);
2343 	intr_restore(intr);
2344 
2345 	if (PAR_SUCCESS(par)) {
2346 		if (pa != NULL)
2347 			*pa = (par & PAR_PA_MASK) | (va & PAR_LOW_MASK);
2348 		return (true);
2349 	}
2350 
2351 	/*
2352 	 * Fall back to walking the page table. The address translation
2353 	 * instruction may fail when the page is in a break-before-make
2354 	 * sequence. As we only clear the valid bit in said sequence we
2355 	 * can walk the page table to find the physical address.
2356 	 */
2357 
2358 	pte = pmap_l1(kernel_pmap, va);
2359 	if (pte == NULL)
2360 		return (false);
2361 
2362 	/*
2363 	 * A concurrent pmap_update_entry() will clear the entry's valid bit
2364 	 * but leave the rest of the entry unchanged.  Therefore, we treat a
2365 	 * non-zero entry as being valid, and we ignore the valid bit when
2366 	 * determining whether the entry maps a block, page, or table.
2367 	 */
2368 	tpte = pmap_load(pte);
2369 	if (tpte == 0)
2370 		return (false);
2371 	if ((tpte & ATTR_DESCR_TYPE_MASK) == ATTR_DESCR_TYPE_BLOCK) {
2372 		if (pa != NULL)
2373 			*pa = PTE_TO_PHYS(tpte) | (va & L1_OFFSET);
2374 		return (true);
2375 	}
2376 	pte = pmap_l1_to_l2(&tpte, va);
2377 	tpte = pmap_load(pte);
2378 	if (tpte == 0)
2379 		return (false);
2380 	if ((tpte & ATTR_DESCR_TYPE_MASK) == ATTR_DESCR_TYPE_BLOCK) {
2381 		if (pa != NULL)
2382 			*pa = PTE_TO_PHYS(tpte) | (va & L2_OFFSET);
2383 		return (true);
2384 	}
2385 	pte = pmap_l2_to_l3(&tpte, va);
2386 	tpte = pmap_load(pte);
2387 	if (tpte == 0)
2388 		return (false);
2389 	if (pa != NULL)
2390 		*pa = PTE_TO_PHYS(tpte) | (va & L3_OFFSET);
2391 	return (true);
2392 }
2393 
2394 /*
2395  *	Routine:	pmap_kextract
2396  *	Function:
2397  *		Extract the physical page address associated with the given kernel
2398  *		virtual address.
2399  */
2400 vm_paddr_t
2401 pmap_kextract(vm_offset_t va)
2402 {
2403 	vm_paddr_t pa;
2404 
2405 	if (va >= DMAP_MIN_ADDRESS && va < DMAP_MAX_ADDRESS)
2406 		return (DMAP_TO_PHYS(va));
2407 
2408 	if (pmap_klookup(va, &pa) == false)
2409 		return (0);
2410 	return (pa);
2411 }
2412 
2413 /***************************************************
2414  * Low level mapping routines.....
2415  ***************************************************/
2416 
2417 void
2418 pmap_kenter(vm_offset_t sva, vm_size_t size, vm_paddr_t pa, int mode)
2419 {
2420 	pd_entry_t *pde;
2421 	pt_entry_t attr, old_l3e, *pte;
2422 	vm_offset_t va;
2423 	vm_page_t mpte;
2424 	int error, lvl;
2425 
2426 	KASSERT((pa & L3_OFFSET) == 0,
2427 	    ("pmap_kenter: Invalid physical address"));
2428 	KASSERT((sva & L3_OFFSET) == 0,
2429 	    ("pmap_kenter: Invalid virtual address"));
2430 	KASSERT((size & PAGE_MASK) == 0,
2431 	    ("pmap_kenter: Mapping is not page-sized"));
2432 
2433 	/* CCA - Map devices as nonsecure */
2434 	if (in_realm() && (mode == VM_MEMATTR_DEVICE ||
2435 	    mode == VM_MEMATTR_DEVICE_NP))
2436 		pa |= prot_ns_shared_pa;
2437 
2438 	attr = ATTR_AF | pmap_sh_attr | ATTR_S1_AP(ATTR_S1_AP_RW) |
2439 	    ATTR_S1_XN | ATTR_KERN_GP | ATTR_S1_IDX(mode);
2440 	old_l3e = 0;
2441 	va = sva;
2442 	while (size != 0) {
2443 		pde = pmap_pde(kernel_pmap, va, &lvl);
2444 		KASSERT(pde != NULL,
2445 		    ("pmap_kenter: Invalid page entry, va: 0x%lx", va));
2446 		KASSERT(lvl == 2, ("pmap_kenter: Invalid level %d", lvl));
2447 
2448 		/*
2449 		 * If we have an aligned, contiguous chunk of L2_SIZE, try
2450 		 * to create an L2_BLOCK mapping.
2451 		 */
2452 		if ((va & L2_OFFSET) == 0 && size >= L2_SIZE &&
2453 		    (pa & L2_OFFSET) == 0 && vm_initialized) {
2454 			mpte = PTE_TO_VM_PAGE(pmap_load(pde));
2455 			KASSERT(pmap_every_pte_zero(VM_PAGE_TO_PHYS(mpte)),
2456 			    ("pmap_kenter: Unexpected mapping"));
2457 			PMAP_LOCK(kernel_pmap);
2458 			error = pmap_insert_pt_page(kernel_pmap, mpte, false,
2459 			    false);
2460 			if (error == 0) {
2461 				attr &= ~ATTR_CONTIGUOUS;
2462 
2463 				/*
2464 				 * Although the page table page "mpte" should
2465 				 * be devoid of mappings, the TLB might hold
2466 				 * intermediate entries that reference it, so
2467 				 * we perform a single-page invalidation.
2468 				 */
2469 				pmap_update_entry(kernel_pmap, pde,
2470 				    PHYS_TO_PTE(pa) | attr | L2_BLOCK, va,
2471 				    PAGE_SIZE);
2472 			}
2473 			PMAP_UNLOCK(kernel_pmap);
2474 			if (error == 0) {
2475 				va += L2_SIZE;
2476 				pa += L2_SIZE;
2477 				size -= L2_SIZE;
2478 				continue;
2479 			}
2480 		}
2481 
2482 		/*
2483 		 * If we have an aligned, contiguous chunk of L3C_ENTRIES
2484 		 * L3 pages, set the contiguous bit within each PTE so that
2485 		 * the chunk can be cached using only one TLB entry.
2486 		 */
2487 		if ((va & L3C_OFFSET) == 0 && (pa & L3C_OFFSET) == 0) {
2488 			if (size >= L3C_SIZE)
2489 				attr |= ATTR_CONTIGUOUS;
2490 			else
2491 				attr &= ~ATTR_CONTIGUOUS;
2492 		}
2493 
2494 		pte = pmap_l2_to_l3(pde, va);
2495 		old_l3e |= pmap_load_store(pte, PHYS_TO_PTE(pa) | attr |
2496 		    L3_PAGE);
2497 
2498 		va += PAGE_SIZE;
2499 		pa += PAGE_SIZE;
2500 		size -= PAGE_SIZE;
2501 	}
2502 	if ((old_l3e & ATTR_DESCR_VALID) != 0)
2503 		pmap_s1_invalidate_range(kernel_pmap, sva, va, true);
2504 	else {
2505 		/*
2506 		 * Because the old entries were invalid and the new mappings
2507 		 * are not executable, an isb is not required.
2508 		 */
2509 		dsb(ishst);
2510 	}
2511 }
2512 
2513 void
2514 pmap_kenter_device(vm_offset_t sva, vm_size_t size, vm_paddr_t pa)
2515 {
2516 
2517 	pmap_kenter(sva, size, pa, VM_MEMATTR_DEVICE);
2518 }
2519 
2520 /*
2521  * Remove a page from the kernel pagetables.
2522  */
2523 void
2524 pmap_kremove(vm_offset_t va)
2525 {
2526 	pt_entry_t *pte;
2527 
2528 	pte = pmap_pte_exists(kernel_pmap, va, 3, __func__);
2529 	KASSERT((pmap_load(pte) & ATTR_CONTIGUOUS) == 0,
2530 	    ("pmap_kremove: unexpected ATTR_CONTIGUOUS"));
2531 	pmap_clear(pte);
2532 	pmap_s1_invalidate_page(kernel_pmap, va, true);
2533 }
2534 
2535 /*
2536  * Remove the specified range of mappings from the kernel address space.
2537  *
2538  * Should only be applied to mappings that were created by pmap_kenter() or
2539  * pmap_kenter_device().  Nothing about this function is actually specific
2540  * to device mappings.
2541  */
2542 void
2543 pmap_kremove_device(vm_offset_t sva, vm_size_t size)
2544 {
2545 	pt_entry_t *ptep, *ptep_end;
2546 	vm_offset_t va;
2547 	int lvl;
2548 
2549 	KASSERT((sva & L3_OFFSET) == 0,
2550 	    ("pmap_kremove_device: Invalid virtual address"));
2551 	KASSERT((size & PAGE_MASK) == 0,
2552 	    ("pmap_kremove_device: Mapping is not page-sized"));
2553 
2554 	va = sva;
2555 	while (size != 0) {
2556 		ptep = pmap_pte(kernel_pmap, va, &lvl);
2557 		KASSERT(ptep != NULL, ("Invalid page table, va: 0x%lx", va));
2558 		switch (lvl) {
2559 		case 2:
2560 			KASSERT((va & L2_OFFSET) == 0,
2561 			    ("Unaligned virtual address"));
2562 			KASSERT(size >= L2_SIZE, ("Insufficient size"));
2563 
2564 			if (va != sva) {
2565 				pmap_s1_invalidate_range(kernel_pmap, sva, va,
2566 				    true);
2567 			}
2568 			pmap_clear(ptep);
2569 			pmap_s1_invalidate_page(kernel_pmap, va, true);
2570 			PMAP_LOCK(kernel_pmap);
2571 			pmap_remove_kernel_l2(kernel_pmap, ptep, va);
2572 			PMAP_UNLOCK(kernel_pmap);
2573 
2574 			va += L2_SIZE;
2575 			sva = va;
2576 			size -= L2_SIZE;
2577 			break;
2578 		case 3:
2579 			if ((pmap_load(ptep) & ATTR_CONTIGUOUS) != 0) {
2580 				KASSERT((va & L3C_OFFSET) == 0,
2581 				    ("Unaligned L3C virtual address"));
2582 				KASSERT(size >= L3C_SIZE,
2583 				    ("Insufficient L3C size"));
2584 
2585 				ptep_end = ptep + L3C_ENTRIES;
2586 				for (; ptep < ptep_end; ptep++)
2587 					pmap_clear(ptep);
2588 
2589 				va += L3C_SIZE;
2590 				size -= L3C_SIZE;
2591 				break;
2592 			}
2593 			pmap_clear(ptep);
2594 
2595 			va += PAGE_SIZE;
2596 			size -= PAGE_SIZE;
2597 			break;
2598 		default:
2599 			__assert_unreachable();
2600 			break;
2601 		}
2602 	}
2603 	if (va != sva)
2604 		pmap_s1_invalidate_range(kernel_pmap, sva, va, true);
2605 }
2606 
2607 /*
2608  *	Used to map a range of physical addresses into kernel
2609  *	virtual address space.
2610  *
2611  *	The value passed in '*virt' is a suggested virtual address for
2612  *	the mapping. Architectures which can support a direct-mapped
2613  *	physical to virtual region can return the appropriate address
2614  *	within that region, leaving '*virt' unchanged. Other
2615  *	architectures should map the pages starting at '*virt' and
2616  *	update '*virt' with the first usable address after the mapped
2617  *	region.
2618  */
2619 void *
2620 pmap_map(vm_offset_t *virt, vm_paddr_t start, vm_paddr_t end, int prot)
2621 {
2622 	return (PHYS_TO_DMAP(start));
2623 }
2624 
2625 /*
2626  * Add a list of wired pages to the kva
2627  * this routine is only used for temporary
2628  * kernel mappings that do not need to have
2629  * page modification or references recorded.
2630  * Note that old mappings are simply written
2631  * over.  The page *must* be wired.
2632  * Note: SMP coherent.  Uses a ranged shootdown IPI.
2633  */
2634 void
2635 pmap_qenter(void *sva, vm_page_t *ma, int count)
2636 {
2637 	pd_entry_t *pde;
2638 	pt_entry_t attr, old_l3e, *pte;
2639 	vm_offset_t va;
2640 	vm_page_t m;
2641 	int i, lvl;
2642 
2643 	old_l3e = 0;
2644 	va = (vm_offset_t)sva;
2645 	for (i = 0; i < count; i++) {
2646 		pde = pmap_pde(kernel_pmap, va, &lvl);
2647 		KASSERT(pde != NULL,
2648 		    ("pmap_qenter: Invalid page entry, va: 0x%lx", va));
2649 		KASSERT(lvl == 2,
2650 		    ("pmap_qenter: Invalid level %d", lvl));
2651 
2652 		m = ma[i];
2653 		attr = ATTR_AF | pmap_sh_attr |
2654 		    ATTR_S1_AP(ATTR_S1_AP_RW) | ATTR_S1_XN |
2655 		    ATTR_KERN_GP | ATTR_S1_IDX(m->md.pv_memattr) | L3_PAGE;
2656 		pte = pmap_l2_to_l3(pde, va);
2657 		old_l3e |= pmap_load_store(pte, VM_PAGE_TO_PTE(m) | attr);
2658 
2659 		va += L3_SIZE;
2660 	}
2661 	if ((old_l3e & ATTR_DESCR_VALID) != 0)
2662 		pmap_s1_invalidate_range(kernel_pmap, (vm_offset_t)sva, va,
2663 		    true);
2664 	else {
2665 		/*
2666 		 * Because the old entries were invalid and the new mappings
2667 		 * are not executable, an isb is not required.
2668 		 */
2669 		dsb(ishst);
2670 	}
2671 }
2672 
2673 /*
2674  * This routine tears out page mappings from the
2675  * kernel -- it is meant only for temporary mappings.
2676  */
2677 void
2678 pmap_qremove(void *sva, int count)
2679 {
2680 	pt_entry_t *pte;
2681 	vm_offset_t va;
2682 
2683 	va = (vm_offset_t)sva;
2684 
2685 	KASSERT(ADDR_IS_CANONICAL(va),
2686 	    ("%s: Address not in canonical form: %p", __func__, sva));
2687 	KASSERT(ADDR_IS_KERNEL(va), ("usermode va %p", sva));
2688 
2689 	while (count-- > 0) {
2690 		pte = pmap_pte_exists(kernel_pmap, va, 3, NULL);
2691 		if (pte != NULL) {
2692 			pmap_clear(pte);
2693 		}
2694 
2695 		va += PAGE_SIZE;
2696 	}
2697 	pmap_s1_invalidate_range(kernel_pmap, (vm_offset_t)sva, va, true);
2698 }
2699 
2700 /***************************************************
2701  * Page table page management routines.....
2702  ***************************************************/
2703 /*
2704  * Schedule the specified unused page table page to be freed.  Specifically,
2705  * add the page to the specified list of pages that will be released to the
2706  * physical memory manager after the TLB has been updated.
2707  */
2708 static __inline void
2709 pmap_add_delayed_free_list(vm_page_t m, struct spglist *free, bool set_PG_ZERO)
2710 {
2711 
2712 	if (set_PG_ZERO)
2713 		m->flags |= PG_ZERO;
2714 	else
2715 		m->flags &= ~PG_ZERO;
2716 	SLIST_INSERT_HEAD(free, m, plinks.s.ss);
2717 }
2718 
2719 /*
2720  * Decrements a page table page's reference count, which is used to record the
2721  * number of valid page table entries within the page.  If the reference count
2722  * drops to zero, then the page table page is unmapped.  Returns true if the
2723  * page table page was unmapped and false otherwise.
2724  */
2725 static inline bool
2726 pmap_unwire_l3(pmap_t pmap, vm_offset_t va, vm_page_t m, struct spglist *free)
2727 {
2728 
2729 	--m->ref_count;
2730 	if (m->ref_count == 0) {
2731 		_pmap_unwire_l3(pmap, va, m, free);
2732 		return (true);
2733 	} else
2734 		return (false);
2735 }
2736 
2737 static void
2738 _pmap_unwire_l3(pmap_t pmap, vm_offset_t va, vm_page_t m, struct spglist *free)
2739 {
2740 
2741 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
2742 	/*
2743 	 * unmap the page table page
2744 	 */
2745 	if (m->pindex >= (NUL2E + NUL1E)) {
2746 		/* l1 page */
2747 		pd_entry_t *l0;
2748 
2749 		l0 = pmap_l0(pmap, va);
2750 		pmap_clear(l0);
2751 	} else if (m->pindex >= NUL2E) {
2752 		/* l2 page */
2753 		pd_entry_t *l1;
2754 
2755 		l1 = pmap_l1(pmap, va);
2756 		pmap_clear(l1);
2757 	} else {
2758 		/* l3 page */
2759 		pd_entry_t *l2;
2760 
2761 		l2 = pmap_l2(pmap, va);
2762 		pmap_clear(l2);
2763 	}
2764 	pmap_resident_count_dec(pmap, 1);
2765 	if (m->pindex < NUL2E) {
2766 		/* We just released an l3, unhold the matching l2 */
2767 		pd_entry_t *l1, tl1;
2768 		vm_page_t l2pg;
2769 
2770 		l1 = pmap_l1(pmap, va);
2771 		tl1 = pmap_load(l1);
2772 		l2pg = PTE_TO_VM_PAGE(tl1);
2773 		pmap_unwire_l3(pmap, va, l2pg, free);
2774 	} else if (m->pindex < (NUL2E + NUL1E)) {
2775 		/* We just released an l2, unhold the matching l1 */
2776 		pd_entry_t *l0, tl0;
2777 		vm_page_t l1pg;
2778 
2779 		l0 = pmap_l0(pmap, va);
2780 		tl0 = pmap_load(l0);
2781 		l1pg = PTE_TO_VM_PAGE(tl0);
2782 		pmap_unwire_l3(pmap, va, l1pg, free);
2783 	}
2784 	pmap_invalidate_page(pmap, va, false);
2785 
2786 	/*
2787 	 * Put page on a list so that it is released after
2788 	 * *ALL* TLB shootdown is done
2789 	 */
2790 	pmap_add_delayed_free_list(m, free, true);
2791 }
2792 
2793 /*
2794  * After removing a page table entry, this routine is used to
2795  * conditionally free the page, and manage the reference count.
2796  */
2797 static int
2798 pmap_unuse_pt(pmap_t pmap, vm_offset_t va, pd_entry_t ptepde,
2799     struct spglist *free)
2800 {
2801 	vm_page_t mpte;
2802 
2803 	KASSERT(ADDR_IS_CANONICAL(va),
2804 	    ("%s: Address not in canonical form: %lx", __func__, va));
2805 	if (ADDR_IS_KERNEL(va))
2806 		return (0);
2807 	KASSERT(ptepde != 0, ("pmap_unuse_pt: ptepde != 0"));
2808 	mpte = PTE_TO_VM_PAGE(ptepde);
2809 	return (pmap_unwire_l3(pmap, va, mpte, free));
2810 }
2811 
2812 /*
2813  * Release a page table page reference after a failed attempt to create a
2814  * mapping.
2815  */
2816 static void
2817 pmap_abort_ptp(pmap_t pmap, vm_offset_t va, vm_page_t mpte)
2818 {
2819 	struct spglist free;
2820 
2821 	SLIST_INIT(&free);
2822 	if (pmap_unwire_l3(pmap, va, mpte, &free))
2823 		vm_page_free_pages_toq(&free, true);
2824 }
2825 
2826 void
2827 pmap_pinit0(pmap_t pmap)
2828 {
2829 
2830 	PMAP_LOCK_INIT(pmap);
2831 	bzero(&pmap->pm_stats, sizeof(pmap->pm_stats));
2832 	pmap->pm_l0_paddr = READ_SPECIALREG(ttbr0_el1);
2833 	pmap->pm_l0 = PHYS_TO_DMAP(pmap->pm_l0_paddr);
2834 	TAILQ_INIT(&pmap->pm_pvchunk);
2835 	vm_radix_init(&pmap->pm_root);
2836 	pmap->pm_cookie = COOKIE_FROM(ASID_RESERVED_FOR_PID_0, INT_MIN);
2837 	pmap->pm_stage = PM_STAGE1;
2838 	pmap->pm_levels = 4;
2839 	pmap->pm_ttbr = pmap->pm_l0_paddr;
2840 	pmap->pm_asid_set = &asids;
2841 	pmap->pm_bti = NULL;
2842 
2843 	PCPU_SET(curpmap, pmap);
2844 }
2845 
2846 int
2847 pmap_pinit_stage(pmap_t pmap, enum pmap_stage stage, int levels)
2848 {
2849 	vm_page_t m;
2850 
2851 	/*
2852 	 * allocate the l0 page
2853 	 */
2854 	m = vm_page_alloc_noobj(VM_ALLOC_WAITOK | VM_ALLOC_WIRED |
2855 	    VM_ALLOC_ZERO);
2856 	pmap->pm_l0_paddr = VM_PAGE_TO_PHYS(m);
2857 	pmap->pm_l0 = PHYS_TO_DMAP(pmap->pm_l0_paddr);
2858 
2859 	TAILQ_INIT(&pmap->pm_pvchunk);
2860 	vm_radix_init(&pmap->pm_root);
2861 	bzero(&pmap->pm_stats, sizeof(pmap->pm_stats));
2862 	pmap->pm_cookie = COOKIE_FROM(-1, INT_MAX);
2863 
2864 	MPASS(levels == 3 || levels == 4);
2865 	pmap->pm_levels = levels;
2866 	pmap->pm_stage = stage;
2867 	pmap->pm_bti = NULL;
2868 	switch (stage) {
2869 	case PM_STAGE1:
2870 		pmap->pm_asid_set = &asids;
2871 		if (pmap_bti_support) {
2872 			pmap->pm_bti = malloc(sizeof(struct rangeset), M_DEVBUF,
2873 			    M_ZERO | M_WAITOK);
2874 			rangeset_init(pmap->pm_bti, bti_dup_range,
2875 			    bti_free_range, pmap, M_NOWAIT);
2876 		}
2877 		break;
2878 	case PM_STAGE2:
2879 		pmap->pm_asid_set = &vmids;
2880 		break;
2881 	default:
2882 		panic("%s: Invalid pmap type %d", __func__, stage);
2883 		break;
2884 	}
2885 
2886 	/* XXX Temporarily disable deferred ASID allocation. */
2887 	pmap_alloc_asid(pmap);
2888 
2889 	/*
2890 	 * Allocate the level 1 entry to use as the root. This will increase
2891 	 * the refcount on the level 1 page so it won't be removed until
2892 	 * pmap_release() is called.
2893 	 */
2894 	if (pmap->pm_levels == 3) {
2895 		PMAP_LOCK(pmap);
2896 		m = _pmap_alloc_l3(pmap, NUL2E + NUL1E, NULL);
2897 		PMAP_UNLOCK(pmap);
2898 	}
2899 	pmap->pm_ttbr = VM_PAGE_TO_PHYS(m);
2900 
2901 	return (1);
2902 }
2903 
2904 int
2905 pmap_pinit(pmap_t pmap)
2906 {
2907 
2908 	return (pmap_pinit_stage(pmap, PM_STAGE1, 4));
2909 }
2910 
2911 /*
2912  * This routine is called if the desired page table page does not exist.
2913  *
2914  * If page table page allocation fails, this routine may sleep before
2915  * returning NULL.  It sleeps only if a lock pointer was given.
2916  *
2917  * Note: If a page allocation fails at page table level two or three,
2918  * one or two pages may be held during the wait, only to be released
2919  * afterwards.  This conservative approach is easily argued to avoid
2920  * race conditions.
2921  */
2922 static vm_page_t
2923 _pmap_alloc_l3(pmap_t pmap, vm_pindex_t ptepindex, struct rwlock **lockp)
2924 {
2925 	vm_page_t m, l1pg, l2pg;
2926 
2927 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
2928 
2929 	/*
2930 	 * Allocate a page table page.
2931 	 */
2932 	if ((m = vm_page_alloc_noobj(VM_ALLOC_WIRED | VM_ALLOC_ZERO)) == NULL) {
2933 		if (lockp != NULL) {
2934 			RELEASE_PV_LIST_LOCK(lockp);
2935 			PMAP_UNLOCK(pmap);
2936 			vm_wait(NULL);
2937 			PMAP_LOCK(pmap);
2938 		}
2939 
2940 		/*
2941 		 * Indicate the need to retry.  While waiting, the page table
2942 		 * page may have been allocated.
2943 		 */
2944 		return (NULL);
2945 	}
2946 	m->pindex = ptepindex;
2947 
2948 	/*
2949 	 * Because of AArch64's weak memory consistency model, we must have a
2950 	 * barrier here to ensure that the stores for zeroing "m", whether by
2951 	 * pmap_zero_page() or an earlier function, are visible before adding
2952 	 * "m" to the page table.  Otherwise, a page table walk by another
2953 	 * processor's MMU could see the mapping to "m" and a stale, non-zero
2954 	 * PTE within "m".
2955 	 */
2956 	dmb(ishst);
2957 
2958 	/*
2959 	 * Map the pagetable page into the process address space, if
2960 	 * it isn't already there.
2961 	 */
2962 
2963 	if (ptepindex >= (NUL2E + NUL1E)) {
2964 		pd_entry_t *l0p, l0e;
2965 		vm_pindex_t l0index;
2966 
2967 		l0index = ptepindex - (NUL2E + NUL1E);
2968 		l0p = &pmap->pm_l0[l0index];
2969 		KASSERT((pmap_load(l0p) & ATTR_DESCR_VALID) == 0,
2970 		    ("%s: L0 entry %#lx is valid", __func__, pmap_load(l0p)));
2971 		l0e = VM_PAGE_TO_PTE(m) | L0_TABLE;
2972 
2973 		/*
2974 		 * Mark all kernel memory as not accessible from userspace
2975 		 * and userspace memory as not executable from the kernel.
2976 		 * This has been done for the bootstrap L0 entries in
2977 		 * locore.S.
2978 		 */
2979 		if (pmap == kernel_pmap)
2980 			l0e |= TATTR_UXN_TABLE | TATTR_AP_TABLE_NO_EL0;
2981 		else
2982 			l0e |= TATTR_PXN_TABLE;
2983 		pmap_store(l0p, l0e);
2984 	} else if (ptepindex >= NUL2E) {
2985 		vm_pindex_t l0index, l1index;
2986 		pd_entry_t *l0, *l1;
2987 		pd_entry_t tl0;
2988 
2989 		l1index = ptepindex - NUL2E;
2990 		l0index = l1index >> Ln_ENTRIES_SHIFT;
2991 
2992 		l0 = &pmap->pm_l0[l0index];
2993 		tl0 = pmap_load(l0);
2994 		if (tl0 == 0) {
2995 			/* recurse for allocating page dir */
2996 			if (_pmap_alloc_l3(pmap, NUL2E + NUL1E + l0index,
2997 			    lockp) == NULL) {
2998 				vm_page_unwire_noq(m);
2999 				vm_page_free_zero(m);
3000 				return (NULL);
3001 			}
3002 		} else {
3003 			l1pg = PTE_TO_VM_PAGE(tl0);
3004 			l1pg->ref_count++;
3005 		}
3006 
3007 		l1 = PHYS_TO_DMAP(PTE_TO_PHYS(pmap_load(l0)));
3008 		l1 = &l1[ptepindex & Ln_ADDR_MASK];
3009 		KASSERT((pmap_load(l1) & ATTR_DESCR_VALID) == 0,
3010 		    ("%s: L1 entry %#lx is valid", __func__, pmap_load(l1)));
3011 		pmap_store(l1, VM_PAGE_TO_PTE(m) | L1_TABLE);
3012 	} else {
3013 		vm_pindex_t l0index, l1index;
3014 		pd_entry_t *l0, *l1, *l2;
3015 		pd_entry_t tl0, tl1;
3016 
3017 		l1index = ptepindex >> Ln_ENTRIES_SHIFT;
3018 		l0index = l1index >> Ln_ENTRIES_SHIFT;
3019 
3020 		l0 = &pmap->pm_l0[l0index];
3021 		tl0 = pmap_load(l0);
3022 		if (tl0 == 0) {
3023 			/* recurse for allocating page dir */
3024 			if (_pmap_alloc_l3(pmap, NUL2E + l1index,
3025 			    lockp) == NULL) {
3026 				vm_page_unwire_noq(m);
3027 				vm_page_free_zero(m);
3028 				return (NULL);
3029 			}
3030 			tl0 = pmap_load(l0);
3031 			l1 = PHYS_TO_DMAP(PTE_TO_PHYS(tl0));
3032 			l1 = &l1[l1index & Ln_ADDR_MASK];
3033 		} else {
3034 			l1 = PHYS_TO_DMAP(PTE_TO_PHYS(tl0));
3035 			l1 = &l1[l1index & Ln_ADDR_MASK];
3036 			tl1 = pmap_load(l1);
3037 			if (tl1 == 0) {
3038 				/* recurse for allocating page dir */
3039 				if (_pmap_alloc_l3(pmap, NUL2E + l1index,
3040 				    lockp) == NULL) {
3041 					vm_page_unwire_noq(m);
3042 					vm_page_free_zero(m);
3043 					return (NULL);
3044 				}
3045 			} else {
3046 				l2pg = PTE_TO_VM_PAGE(tl1);
3047 				l2pg->ref_count++;
3048 			}
3049 		}
3050 
3051 		l2 = PHYS_TO_DMAP(PTE_TO_PHYS(pmap_load(l1)));
3052 		l2 = &l2[ptepindex & Ln_ADDR_MASK];
3053 		KASSERT((pmap_load(l2) & ATTR_DESCR_VALID) == 0,
3054 		    ("%s: L2 entry %#lx is valid", __func__, pmap_load(l2)));
3055 		pmap_store(l2, VM_PAGE_TO_PTE(m) | L2_TABLE);
3056 	}
3057 
3058 	pmap_resident_count_inc(pmap, 1);
3059 
3060 	return (m);
3061 }
3062 
3063 static pd_entry_t *
3064 pmap_alloc_l2(pmap_t pmap, vm_offset_t va, vm_page_t *l2pgp,
3065     struct rwlock **lockp)
3066 {
3067 	pd_entry_t *l1, *l2;
3068 	vm_page_t l2pg;
3069 	vm_pindex_t l2pindex;
3070 
3071 	KASSERT(ADDR_IS_CANONICAL(va),
3072 	    ("%s: Address not in canonical form: %lx", __func__, va));
3073 
3074 retry:
3075 	l1 = pmap_l1(pmap, va);
3076 	if (l1 != NULL && (pmap_load(l1) & ATTR_DESCR_MASK) == L1_TABLE) {
3077 		l2 = pmap_l1_to_l2(l1, va);
3078 		if (ADDR_IS_USER(va)) {
3079 			/* Add a reference to the L2 page. */
3080 			l2pg = PTE_TO_VM_PAGE(pmap_load(l1));
3081 			l2pg->ref_count++;
3082 		} else
3083 			l2pg = NULL;
3084 	} else if (ADDR_IS_USER(va)) {
3085 		/* Allocate a L2 page. */
3086 		l2pindex = pmap_l2_pindex(va) >> Ln_ENTRIES_SHIFT;
3087 		l2pg = _pmap_alloc_l3(pmap, NUL2E + l2pindex, lockp);
3088 		if (l2pg == NULL) {
3089 			if (lockp != NULL)
3090 				goto retry;
3091 			else
3092 				return (NULL);
3093 		}
3094 		l2 = VM_PAGE_TO_DMAP(l2pg);
3095 		l2 = &l2[pmap_l2_index(va)];
3096 	} else
3097 		panic("pmap_alloc_l2: missing page table page for va %#lx",
3098 		    va);
3099 	*l2pgp = l2pg;
3100 	return (l2);
3101 }
3102 
3103 static vm_page_t
3104 pmap_alloc_l3(pmap_t pmap, vm_offset_t va, struct rwlock **lockp)
3105 {
3106 	vm_pindex_t ptepindex;
3107 	pd_entry_t *pde, tpde;
3108 #ifdef INVARIANTS
3109 	pt_entry_t *pte;
3110 #endif
3111 	vm_page_t m;
3112 	int lvl;
3113 
3114 	/*
3115 	 * Calculate pagetable page index
3116 	 */
3117 	ptepindex = pmap_l2_pindex(va);
3118 retry:
3119 	/*
3120 	 * Get the page directory entry
3121 	 */
3122 	pde = pmap_pde(pmap, va, &lvl);
3123 
3124 	/*
3125 	 * If the page table page is mapped, we just increment the hold count,
3126 	 * and activate it. If we get a level 2 pde it will point to a level 3
3127 	 * table.
3128 	 */
3129 	switch (lvl) {
3130 	case -1:
3131 		break;
3132 	case 0:
3133 #ifdef INVARIANTS
3134 		pte = pmap_l0_to_l1(pde, va);
3135 		KASSERT(pmap_load(pte) == 0,
3136 		    ("pmap_alloc_l3: TODO: l0 superpages"));
3137 #endif
3138 		break;
3139 	case 1:
3140 #ifdef INVARIANTS
3141 		pte = pmap_l1_to_l2(pde, va);
3142 		KASSERT(pmap_load(pte) == 0,
3143 		    ("pmap_alloc_l3: TODO: l1 superpages"));
3144 #endif
3145 		break;
3146 	case 2:
3147 		tpde = pmap_load(pde);
3148 		if (tpde != 0) {
3149 			m = PTE_TO_VM_PAGE(tpde);
3150 			m->ref_count++;
3151 			return (m);
3152 		}
3153 		break;
3154 	default:
3155 		panic("pmap_alloc_l3: Invalid level %d", lvl);
3156 	}
3157 
3158 	/*
3159 	 * Here if the pte page isn't mapped, or if it has been deallocated.
3160 	 */
3161 	m = _pmap_alloc_l3(pmap, ptepindex, lockp);
3162 	if (m == NULL && lockp != NULL)
3163 		goto retry;
3164 
3165 	return (m);
3166 }
3167 
3168 /***************************************************
3169  * Pmap allocation/deallocation routines.
3170  ***************************************************/
3171 
3172 /*
3173  * Release any resources held by the given physical map.
3174  * Called when a pmap initialized by pmap_pinit is being released.
3175  * Should only be called if the map contains no valid mappings.
3176  */
3177 void
3178 pmap_release(pmap_t pmap)
3179 {
3180 	bool rv __diagused;
3181 	struct spglist freelist;
3182 	struct asid_set *set;
3183 	vm_page_t m;
3184 	int asid;
3185 
3186 	if (pmap->pm_levels != 4) {
3187 		PMAP_ASSERT_STAGE2(pmap);
3188 		KASSERT(pmap->pm_stats.resident_count == 1,
3189 		    ("pmap_release: pmap resident count %ld != 0",
3190 		    pmap->pm_stats.resident_count));
3191 		KASSERT((pmap->pm_l0[0] & ATTR_DESCR_VALID) == ATTR_DESCR_VALID,
3192 		    ("pmap_release: Invalid l0 entry: %lx", pmap->pm_l0[0]));
3193 
3194 		SLIST_INIT(&freelist);
3195 		m = PHYS_TO_VM_PAGE(pmap->pm_ttbr);
3196 		PMAP_LOCK(pmap);
3197 		rv = pmap_unwire_l3(pmap, 0, m, &freelist);
3198 		PMAP_UNLOCK(pmap);
3199 		MPASS(rv == true);
3200 		vm_page_free_pages_toq(&freelist, true);
3201 	}
3202 
3203 	KASSERT(pmap->pm_stats.resident_count == 0,
3204 	    ("pmap_release: pmap resident count %ld != 0",
3205 	    pmap->pm_stats.resident_count));
3206 	KASSERT(vm_radix_is_empty(&pmap->pm_root),
3207 	    ("pmap_release: pmap has reserved page table page(s)"));
3208 
3209 	set = pmap->pm_asid_set;
3210 	KASSERT(set != NULL, ("%s: NULL asid set", __func__));
3211 
3212 	/*
3213 	 * Allow the ASID to be reused. In stage 2 VMIDs we don't invalidate
3214 	 * the entries when removing them so rely on a later tlb invalidation.
3215 	 * this will happen when updating the VMID generation. Because of this
3216 	 * we don't reuse VMIDs within a generation.
3217 	 */
3218 	if (pmap->pm_stage == PM_STAGE1) {
3219 		mtx_lock_spin(&set->asid_set_mutex);
3220 		if (COOKIE_TO_EPOCH(pmap->pm_cookie) == set->asid_epoch) {
3221 			asid = COOKIE_TO_ASID(pmap->pm_cookie);
3222 			KASSERT(asid >= ASID_FIRST_AVAILABLE &&
3223 			    asid < set->asid_set_size,
3224 			    ("pmap_release: pmap cookie has out-of-range asid"));
3225 			bit_clear(set->asid_set, asid);
3226 		}
3227 		mtx_unlock_spin(&set->asid_set_mutex);
3228 
3229 		if (pmap->pm_bti != NULL) {
3230 			rangeset_fini(pmap->pm_bti);
3231 			free(pmap->pm_bti, M_DEVBUF);
3232 		}
3233 	}
3234 
3235 	m = PHYS_TO_VM_PAGE(pmap->pm_l0_paddr);
3236 	vm_page_unwire_noq(m);
3237 	vm_page_free_zero(m);
3238 }
3239 
3240 static int
3241 kvm_size(SYSCTL_HANDLER_ARGS)
3242 {
3243 	unsigned long ksize = VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS;
3244 
3245 	return sysctl_handle_long(oidp, &ksize, 0, req);
3246 }
3247 SYSCTL_PROC(_vm, OID_AUTO, kvm_size, CTLTYPE_LONG | CTLFLAG_RD | CTLFLAG_MPSAFE,
3248     0, 0, kvm_size, "LU",
3249     "Size of KVM");
3250 
3251 static int
3252 kvm_free(SYSCTL_HANDLER_ARGS)
3253 {
3254 	unsigned long kfree = VM_MAX_KERNEL_ADDRESS - kernel_vm_end;
3255 
3256 	return sysctl_handle_long(oidp, &kfree, 0, req);
3257 }
3258 SYSCTL_PROC(_vm, OID_AUTO, kvm_free, CTLTYPE_LONG | CTLFLAG_RD | CTLFLAG_MPSAFE,
3259     0, 0, kvm_free, "LU",
3260     "Amount of KVM free");
3261 
3262 /*
3263  * grow the number of kernel page table entries, if needed
3264  */
3265 static int
3266 pmap_growkernel_nopanic(vm_offset_t addr)
3267 {
3268 	vm_page_t nkpg;
3269 	pd_entry_t *l0, *l1, *l2;
3270 
3271 	mtx_assert(&kernel_map->system_mtx, MA_OWNED);
3272 
3273 	addr = roundup2(addr, L2_SIZE);
3274 	if (addr - 1 >= vm_map_max(kernel_map))
3275 		addr = vm_map_max(kernel_map);
3276 	if (kernel_vm_end < addr) {
3277 		kasan_shadow_map(kernel_vm_end, addr - kernel_vm_end);
3278 		kmsan_shadow_map(kernel_vm_end, addr - kernel_vm_end);
3279 	}
3280 	while (kernel_vm_end < addr) {
3281 		l0 = pmap_l0(kernel_pmap, kernel_vm_end);
3282 		KASSERT(pmap_load(l0) != 0,
3283 		    ("pmap_growkernel: No level 0 kernel entry"));
3284 
3285 		l1 = pmap_l0_to_l1(l0, kernel_vm_end);
3286 		if (pmap_load(l1) == 0) {
3287 			/* We need a new PDP entry */
3288 			nkpg = vm_page_alloc_noobj(VM_ALLOC_INTERRUPT |
3289 			    VM_ALLOC_NOFREE | VM_ALLOC_WIRED | VM_ALLOC_ZERO);
3290 			if (nkpg == NULL)
3291 				return (KERN_RESOURCE_SHORTAGE);
3292 			nkpg->pindex = pmap_l1_pindex(kernel_vm_end);
3293 			/* See the dmb() in _pmap_alloc_l3(). */
3294 			dmb(ishst);
3295 			pmap_store(l1, VM_PAGE_TO_PTE(nkpg) | L1_TABLE);
3296 			continue; /* try again */
3297 		}
3298 		l2 = pmap_l1_to_l2(l1, kernel_vm_end);
3299 		if (pmap_load(l2) != 0) {
3300 			kernel_vm_end = (kernel_vm_end + L2_SIZE) & ~L2_OFFSET;
3301 			if (kernel_vm_end - 1 >= vm_map_max(kernel_map)) {
3302 				kernel_vm_end = vm_map_max(kernel_map);
3303 				break;
3304 			}
3305 			continue;
3306 		}
3307 
3308 		nkpg = vm_page_alloc_noobj(VM_ALLOC_INTERRUPT |
3309 		    VM_ALLOC_NOFREE | VM_ALLOC_WIRED | VM_ALLOC_ZERO);
3310 		if (nkpg == NULL)
3311 			return (KERN_RESOURCE_SHORTAGE);
3312 		nkpg->pindex = pmap_l2_pindex(kernel_vm_end);
3313 		/* See the dmb() in _pmap_alloc_l3(). */
3314 		dmb(ishst);
3315 		pmap_store(l2, VM_PAGE_TO_PTE(nkpg) | L2_TABLE);
3316 
3317 		kernel_vm_end = (kernel_vm_end + L2_SIZE) & ~L2_OFFSET;
3318 		if (kernel_vm_end - 1 >= vm_map_max(kernel_map)) {
3319 			kernel_vm_end = vm_map_max(kernel_map);
3320 			break;
3321 		}
3322 	}
3323 	return (KERN_SUCCESS);
3324 }
3325 
3326 int
3327 pmap_growkernel(vm_offset_t addr)
3328 {
3329 	int rv;
3330 
3331 	rv = pmap_growkernel_nopanic(addr);
3332 	if (rv != KERN_SUCCESS && pmap_growkernel_panic)
3333 		panic("pmap_growkernel: no memory to grow kernel");
3334 	return (rv);
3335 }
3336 
3337 /***************************************************
3338  * page management routines.
3339  ***************************************************/
3340 
3341 static const uint64_t pc_freemask[_NPCM] = {
3342 	[0 ... _NPCM - 2] = PC_FREEN,
3343 	[_NPCM - 1] = PC_FREEL
3344 };
3345 
3346 #ifdef PV_STATS
3347 static int pc_chunk_count, pc_chunk_allocs, pc_chunk_frees, pc_chunk_tryfail;
3348 
3349 SYSCTL_INT(_vm_pmap, OID_AUTO, pc_chunk_count, CTLFLAG_RD, &pc_chunk_count, 0,
3350 	"Current number of pv entry chunks");
3351 SYSCTL_INT(_vm_pmap, OID_AUTO, pc_chunk_allocs, CTLFLAG_RD, &pc_chunk_allocs, 0,
3352 	"Current number of pv entry chunks allocated");
3353 SYSCTL_INT(_vm_pmap, OID_AUTO, pc_chunk_frees, CTLFLAG_RD, &pc_chunk_frees, 0,
3354 	"Current number of pv entry chunks frees");
3355 SYSCTL_INT(_vm_pmap, OID_AUTO, pc_chunk_tryfail, CTLFLAG_RD, &pc_chunk_tryfail, 0,
3356 	"Number of times tried to get a chunk page but failed.");
3357 
3358 static long pv_entry_frees, pv_entry_allocs, pv_entry_count;
3359 static int pv_entry_spare;
3360 
3361 SYSCTL_LONG(_vm_pmap, OID_AUTO, pv_entry_frees, CTLFLAG_RD, &pv_entry_frees, 0,
3362 	"Current number of pv entry frees");
3363 SYSCTL_LONG(_vm_pmap, OID_AUTO, pv_entry_allocs, CTLFLAG_RD, &pv_entry_allocs, 0,
3364 	"Current number of pv entry allocs");
3365 SYSCTL_LONG(_vm_pmap, OID_AUTO, pv_entry_count, CTLFLAG_RD, &pv_entry_count, 0,
3366 	"Current number of pv entries");
3367 SYSCTL_INT(_vm_pmap, OID_AUTO, pv_entry_spare, CTLFLAG_RD, &pv_entry_spare, 0,
3368 	"Current number of spare pv entries");
3369 #endif
3370 
3371 /*
3372  * We are in a serious low memory condition.  Resort to
3373  * drastic measures to free some pages so we can allocate
3374  * another pv entry chunk.
3375  *
3376  * Returns NULL if PV entries were reclaimed from the specified pmap.
3377  *
3378  * We do not, however, unmap 2mpages because subsequent accesses will
3379  * allocate per-page pv entries until repromotion occurs, thereby
3380  * exacerbating the shortage of free pv entries.
3381  */
3382 static vm_page_t
3383 reclaim_pv_chunk_domain(pmap_t locked_pmap, struct rwlock **lockp, int domain)
3384 {
3385 	struct pv_chunks_list *pvc;
3386 	struct pv_chunk *pc, *pc_marker, *pc_marker_end;
3387 	struct pv_chunk_header pc_marker_b, pc_marker_end_b;
3388 	struct md_page *pvh;
3389 	pd_entry_t *pde;
3390 	pmap_t next_pmap, pmap;
3391 	pt_entry_t *pte, tpte;
3392 	pv_entry_t pv;
3393 	vm_offset_t va;
3394 	vm_page_t m, m_pc;
3395 	struct spglist free;
3396 	uint64_t inuse;
3397 	int bit, field, freed, lvl;
3398 
3399 	PMAP_LOCK_ASSERT(locked_pmap, MA_OWNED);
3400 	KASSERT(lockp != NULL, ("reclaim_pv_chunk: lockp is NULL"));
3401 
3402 	pmap = NULL;
3403 	m_pc = NULL;
3404 	SLIST_INIT(&free);
3405 	bzero(&pc_marker_b, sizeof(pc_marker_b));
3406 	bzero(&pc_marker_end_b, sizeof(pc_marker_end_b));
3407 	pc_marker = (struct pv_chunk *)&pc_marker_b;
3408 	pc_marker_end = (struct pv_chunk *)&pc_marker_end_b;
3409 
3410 	pvc = &pv_chunks[domain];
3411 	mtx_lock(&pvc->pvc_lock);
3412 	pvc->active_reclaims++;
3413 	TAILQ_INSERT_HEAD(&pvc->pvc_list, pc_marker, pc_lru);
3414 	TAILQ_INSERT_TAIL(&pvc->pvc_list, pc_marker_end, pc_lru);
3415 	while ((pc = TAILQ_NEXT(pc_marker, pc_lru)) != pc_marker_end &&
3416 	    SLIST_EMPTY(&free)) {
3417 		next_pmap = pc->pc_pmap;
3418 		if (next_pmap == NULL) {
3419 			/*
3420 			 * The next chunk is a marker.  However, it is
3421 			 * not our marker, so active_reclaims must be
3422 			 * > 1.  Consequently, the next_chunk code
3423 			 * will not rotate the pv_chunks list.
3424 			 */
3425 			goto next_chunk;
3426 		}
3427 		mtx_unlock(&pvc->pvc_lock);
3428 
3429 		/*
3430 		 * A pv_chunk can only be removed from the pc_lru list
3431 		 * when both pvc->pvc_lock is owned and the
3432 		 * corresponding pmap is locked.
3433 		 */
3434 		if (pmap != next_pmap) {
3435 			if (pmap != NULL && pmap != locked_pmap)
3436 				PMAP_UNLOCK(pmap);
3437 			pmap = next_pmap;
3438 			/* Avoid deadlock and lock recursion. */
3439 			if (pmap > locked_pmap) {
3440 				RELEASE_PV_LIST_LOCK(lockp);
3441 				PMAP_LOCK(pmap);
3442 				mtx_lock(&pvc->pvc_lock);
3443 				continue;
3444 			} else if (pmap != locked_pmap) {
3445 				if (PMAP_TRYLOCK(pmap)) {
3446 					mtx_lock(&pvc->pvc_lock);
3447 					continue;
3448 				} else {
3449 					pmap = NULL; /* pmap is not locked */
3450 					mtx_lock(&pvc->pvc_lock);
3451 					pc = TAILQ_NEXT(pc_marker, pc_lru);
3452 					if (pc == NULL ||
3453 					    pc->pc_pmap != next_pmap)
3454 						continue;
3455 					goto next_chunk;
3456 				}
3457 			}
3458 		}
3459 
3460 		/*
3461 		 * Destroy every non-wired, 4 KB page mapping in the chunk.
3462 		 */
3463 		freed = 0;
3464 		for (field = 0; field < _NPCM; field++) {
3465 			for (inuse = ~pc->pc_map[field] & pc_freemask[field];
3466 			    inuse != 0; inuse &= ~(1UL << bit)) {
3467 				bit = ffsl(inuse) - 1;
3468 				pv = &pc->pc_pventry[field * 64 + bit];
3469 				va = pv->pv_va;
3470 				pde = pmap_pde(pmap, va, &lvl);
3471 				if (lvl != 2)
3472 					continue;
3473 				pte = pmap_l2_to_l3(pde, va);
3474 				tpte = pmap_load(pte);
3475 				if ((tpte & ATTR_SW_WIRED) != 0)
3476 					continue;
3477 				if ((tpte & ATTR_CONTIGUOUS) != 0)
3478 					(void)pmap_demote_l3c(pmap, pte, va);
3479 				tpte = pmap_load_clear(pte);
3480 				m = PTE_TO_VM_PAGE(tpte);
3481 				if (pmap_pte_dirty(pmap, tpte))
3482 					vm_page_dirty(m);
3483 				if ((tpte & ATTR_AF) != 0) {
3484 					pmap_s1_invalidate_page(pmap, va, true);
3485 					vm_page_aflag_set(m, PGA_REFERENCED);
3486 				}
3487 				CHANGE_PV_LIST_LOCK_TO_VM_PAGE(lockp, m);
3488 				TAILQ_REMOVE(&m->md.pv_list, pv, pv_next);
3489 				m->md.pv_gen++;
3490 				if (TAILQ_EMPTY(&m->md.pv_list) &&
3491 				    (m->flags & PG_FICTITIOUS) == 0) {
3492 					pvh = page_to_pvh(m);
3493 					if (TAILQ_EMPTY(&pvh->pv_list)) {
3494 						vm_page_aflag_clear(m,
3495 						    PGA_WRITEABLE);
3496 					}
3497 				}
3498 				pc->pc_map[field] |= 1UL << bit;
3499 				pmap_unuse_pt(pmap, va, pmap_load(pde), &free);
3500 				freed++;
3501 			}
3502 		}
3503 		if (freed == 0) {
3504 			mtx_lock(&pvc->pvc_lock);
3505 			goto next_chunk;
3506 		}
3507 		/* Every freed mapping is for a 4 KB page. */
3508 		pmap_resident_count_dec(pmap, freed);
3509 		PV_STAT(atomic_add_long(&pv_entry_frees, freed));
3510 		PV_STAT(atomic_add_int(&pv_entry_spare, freed));
3511 		PV_STAT(atomic_subtract_long(&pv_entry_count, freed));
3512 		TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
3513 		if (pc_is_free(pc)) {
3514 			PV_STAT(atomic_subtract_int(&pv_entry_spare, _NPCPV));
3515 			PV_STAT(atomic_subtract_int(&pc_chunk_count, 1));
3516 			PV_STAT(atomic_add_int(&pc_chunk_frees, 1));
3517 			/* Entire chunk is free; return it. */
3518 			m_pc = DMAP_TO_VM_PAGE(pc);
3519 			dump_drop_page(m_pc->phys_addr);
3520 			mtx_lock(&pvc->pvc_lock);
3521 			TAILQ_REMOVE(&pvc->pvc_list, pc, pc_lru);
3522 			break;
3523 		}
3524 		TAILQ_INSERT_HEAD(&pmap->pm_pvchunk, pc, pc_list);
3525 		mtx_lock(&pvc->pvc_lock);
3526 		/* One freed pv entry in locked_pmap is sufficient. */
3527 		if (pmap == locked_pmap)
3528 			break;
3529 
3530 next_chunk:
3531 		TAILQ_REMOVE(&pvc->pvc_list, pc_marker, pc_lru);
3532 		TAILQ_INSERT_AFTER(&pvc->pvc_list, pc, pc_marker, pc_lru);
3533 		if (pvc->active_reclaims == 1 && pmap != NULL) {
3534 			/*
3535 			 * Rotate the pv chunks list so that we do not
3536 			 * scan the same pv chunks that could not be
3537 			 * freed (because they contained a wired
3538 			 * and/or superpage mapping) on every
3539 			 * invocation of reclaim_pv_chunk().
3540 			 */
3541 			while ((pc = TAILQ_FIRST(&pvc->pvc_list)) != pc_marker){
3542 				MPASS(pc->pc_pmap != NULL);
3543 				TAILQ_REMOVE(&pvc->pvc_list, pc, pc_lru);
3544 				TAILQ_INSERT_TAIL(&pvc->pvc_list, pc, pc_lru);
3545 			}
3546 		}
3547 	}
3548 	TAILQ_REMOVE(&pvc->pvc_list, pc_marker, pc_lru);
3549 	TAILQ_REMOVE(&pvc->pvc_list, pc_marker_end, pc_lru);
3550 	pvc->active_reclaims--;
3551 	mtx_unlock(&pvc->pvc_lock);
3552 	if (pmap != NULL && pmap != locked_pmap)
3553 		PMAP_UNLOCK(pmap);
3554 	if (m_pc == NULL && !SLIST_EMPTY(&free)) {
3555 		m_pc = SLIST_FIRST(&free);
3556 		SLIST_REMOVE_HEAD(&free, plinks.s.ss);
3557 		/* Recycle a freed page table page. */
3558 		m_pc->ref_count = 1;
3559 	}
3560 	vm_page_free_pages_toq(&free, true);
3561 	return (m_pc);
3562 }
3563 
3564 static vm_page_t
3565 reclaim_pv_chunk(pmap_t locked_pmap, struct rwlock **lockp)
3566 {
3567 	vm_page_t m;
3568 	int i, domain;
3569 
3570 	domain = PCPU_GET(domain);
3571 	for (i = 0; i < vm_ndomains; i++) {
3572 		m = reclaim_pv_chunk_domain(locked_pmap, lockp, domain);
3573 		if (m != NULL)
3574 			break;
3575 		domain = (domain + 1) % vm_ndomains;
3576 	}
3577 
3578 	return (m);
3579 }
3580 
3581 /*
3582  * free the pv_entry back to the free list
3583  */
3584 static void
3585 free_pv_entry(pmap_t pmap, pv_entry_t pv)
3586 {
3587 	struct pv_chunk *pc;
3588 	int idx, field, bit;
3589 
3590 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
3591 	PV_STAT(atomic_add_long(&pv_entry_frees, 1));
3592 	PV_STAT(atomic_add_int(&pv_entry_spare, 1));
3593 	PV_STAT(atomic_subtract_long(&pv_entry_count, 1));
3594 	pc = pv_to_chunk(pv);
3595 	idx = pv - &pc->pc_pventry[0];
3596 	field = idx / 64;
3597 	bit = idx % 64;
3598 	pc->pc_map[field] |= 1ul << bit;
3599 	if (!pc_is_free(pc)) {
3600 		/* 98% of the time, pc is already at the head of the list. */
3601 		if (__predict_false(pc != TAILQ_FIRST(&pmap->pm_pvchunk))) {
3602 			TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
3603 			TAILQ_INSERT_HEAD(&pmap->pm_pvchunk, pc, pc_list);
3604 		}
3605 		return;
3606 	}
3607 	TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
3608 	free_pv_chunk(pc);
3609 }
3610 
3611 static void
3612 free_pv_chunk_dequeued(struct pv_chunk *pc)
3613 {
3614 	vm_page_t m;
3615 
3616 	PV_STAT(atomic_subtract_int(&pv_entry_spare, _NPCPV));
3617 	PV_STAT(atomic_subtract_int(&pc_chunk_count, 1));
3618 	PV_STAT(atomic_add_int(&pc_chunk_frees, 1));
3619 	/* entire chunk is free, return it */
3620 	m = DMAP_TO_VM_PAGE(pc);
3621 	dump_drop_page(m->phys_addr);
3622 	vm_page_unwire_noq(m);
3623 	vm_page_free(m);
3624 }
3625 
3626 static void
3627 free_pv_chunk(struct pv_chunk *pc)
3628 {
3629 	struct pv_chunks_list *pvc;
3630 
3631 	pvc = &pv_chunks[pc_to_domain(pc)];
3632 	mtx_lock(&pvc->pvc_lock);
3633 	TAILQ_REMOVE(&pvc->pvc_list, pc, pc_lru);
3634 	mtx_unlock(&pvc->pvc_lock);
3635 	free_pv_chunk_dequeued(pc);
3636 }
3637 
3638 static void
3639 free_pv_chunk_batch(struct pv_chunklist *batch)
3640 {
3641 	struct pv_chunks_list *pvc;
3642 	struct pv_chunk *pc, *npc;
3643 	int i;
3644 
3645 	for (i = 0; i < vm_ndomains; i++) {
3646 		if (TAILQ_EMPTY(&batch[i]))
3647 			continue;
3648 		pvc = &pv_chunks[i];
3649 		mtx_lock(&pvc->pvc_lock);
3650 		TAILQ_FOREACH(pc, &batch[i], pc_list) {
3651 			TAILQ_REMOVE(&pvc->pvc_list, pc, pc_lru);
3652 		}
3653 		mtx_unlock(&pvc->pvc_lock);
3654 	}
3655 
3656 	for (i = 0; i < vm_ndomains; i++) {
3657 		TAILQ_FOREACH_SAFE(pc, &batch[i], pc_list, npc) {
3658 			free_pv_chunk_dequeued(pc);
3659 		}
3660 	}
3661 }
3662 
3663 /*
3664  * Returns a new PV entry, allocating a new PV chunk from the system when
3665  * needed.  If this PV chunk allocation fails and a PV list lock pointer was
3666  * given, a PV chunk is reclaimed from an arbitrary pmap.  Otherwise, NULL is
3667  * returned.
3668  *
3669  * The given PV list lock may be released.
3670  */
3671 static pv_entry_t
3672 get_pv_entry(pmap_t pmap, struct rwlock **lockp)
3673 {
3674 	struct pv_chunks_list *pvc;
3675 	int bit, field;
3676 	pv_entry_t pv;
3677 	struct pv_chunk *pc;
3678 	vm_page_t m;
3679 
3680 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
3681 	PV_STAT(atomic_add_long(&pv_entry_allocs, 1));
3682 retry:
3683 	pc = TAILQ_FIRST(&pmap->pm_pvchunk);
3684 	if (pc != NULL) {
3685 		for (field = 0; field < _NPCM; field++) {
3686 			if (pc->pc_map[field]) {
3687 				bit = ffsl(pc->pc_map[field]) - 1;
3688 				break;
3689 			}
3690 		}
3691 		if (field < _NPCM) {
3692 			pv = &pc->pc_pventry[field * 64 + bit];
3693 			pc->pc_map[field] &= ~(1ul << bit);
3694 			/* If this was the last item, move it to tail */
3695 			if (pc_is_full(pc)) {
3696 				TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
3697 				TAILQ_INSERT_TAIL(&pmap->pm_pvchunk, pc,
3698 				    pc_list);
3699 			}
3700 			PV_STAT(atomic_add_long(&pv_entry_count, 1));
3701 			PV_STAT(atomic_subtract_int(&pv_entry_spare, 1));
3702 			return (pv);
3703 		}
3704 	}
3705 	/* No free items, allocate another chunk */
3706 	m = vm_page_alloc_noobj(VM_ALLOC_WIRED);
3707 	if (m == NULL) {
3708 		if (lockp == NULL) {
3709 			PV_STAT(pc_chunk_tryfail++);
3710 			return (NULL);
3711 		}
3712 		m = reclaim_pv_chunk(pmap, lockp);
3713 		if (m == NULL)
3714 			goto retry;
3715 	}
3716 	PV_STAT(atomic_add_int(&pc_chunk_count, 1));
3717 	PV_STAT(atomic_add_int(&pc_chunk_allocs, 1));
3718 	dump_add_page(m->phys_addr);
3719 	pc = PHYS_TO_DMAP(m->phys_addr);
3720 	pc->pc_pmap = pmap;
3721 	memcpy(pc->pc_map, pc_freemask, sizeof(pc_freemask));
3722 	pc->pc_map[0] &= ~1ul;		/* preallocated bit 0 */
3723 	pvc = &pv_chunks[vm_page_domain(m)];
3724 	mtx_lock(&pvc->pvc_lock);
3725 	TAILQ_INSERT_TAIL(&pvc->pvc_list, pc, pc_lru);
3726 	mtx_unlock(&pvc->pvc_lock);
3727 	pv = &pc->pc_pventry[0];
3728 	TAILQ_INSERT_HEAD(&pmap->pm_pvchunk, pc, pc_list);
3729 	PV_STAT(atomic_add_long(&pv_entry_count, 1));
3730 	PV_STAT(atomic_add_int(&pv_entry_spare, _NPCPV - 1));
3731 	return (pv);
3732 }
3733 
3734 /*
3735  * Ensure that the number of spare PV entries in the specified pmap meets or
3736  * exceeds the given count, "needed".
3737  *
3738  * The given PV list lock may be released.
3739  */
3740 static void
3741 reserve_pv_entries(pmap_t pmap, int needed, struct rwlock **lockp)
3742 {
3743 	struct pv_chunks_list *pvc;
3744 	struct pch new_tail[PMAP_MEMDOM];
3745 	struct pv_chunk *pc;
3746 	vm_page_t m;
3747 	int avail, free, i;
3748 	bool reclaimed;
3749 
3750 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
3751 	KASSERT(lockp != NULL, ("reserve_pv_entries: lockp is NULL"));
3752 
3753 	/*
3754 	 * Newly allocated PV chunks must be stored in a private list until
3755 	 * the required number of PV chunks have been allocated.  Otherwise,
3756 	 * reclaim_pv_chunk() could recycle one of these chunks.  In
3757 	 * contrast, these chunks must be added to the pmap upon allocation.
3758 	 */
3759 	for (i = 0; i < PMAP_MEMDOM; i++)
3760 		TAILQ_INIT(&new_tail[i]);
3761 retry:
3762 	avail = 0;
3763 	TAILQ_FOREACH(pc, &pmap->pm_pvchunk, pc_list) {
3764 		bit_count((bitstr_t *)pc->pc_map, 0,
3765 		    sizeof(pc->pc_map) * NBBY, &free);
3766 		if (free == 0)
3767 			break;
3768 		avail += free;
3769 		if (avail >= needed)
3770 			break;
3771 	}
3772 	for (reclaimed = false; avail < needed; avail += _NPCPV) {
3773 		m = vm_page_alloc_noobj(VM_ALLOC_WIRED);
3774 		if (m == NULL) {
3775 			m = reclaim_pv_chunk(pmap, lockp);
3776 			if (m == NULL)
3777 				goto retry;
3778 			reclaimed = true;
3779 		}
3780 		PV_STAT(atomic_add_int(&pc_chunk_count, 1));
3781 		PV_STAT(atomic_add_int(&pc_chunk_allocs, 1));
3782 		dump_add_page(m->phys_addr);
3783 		pc = PHYS_TO_DMAP(m->phys_addr);
3784 		pc->pc_pmap = pmap;
3785 		memcpy(pc->pc_map, pc_freemask, sizeof(pc_freemask));
3786 		TAILQ_INSERT_HEAD(&pmap->pm_pvchunk, pc, pc_list);
3787 		TAILQ_INSERT_TAIL(&new_tail[vm_page_domain(m)], pc, pc_lru);
3788 		PV_STAT(atomic_add_int(&pv_entry_spare, _NPCPV));
3789 
3790 		/*
3791 		 * The reclaim might have freed a chunk from the current pmap.
3792 		 * If that chunk contained available entries, we need to
3793 		 * re-count the number of available entries.
3794 		 */
3795 		if (reclaimed)
3796 			goto retry;
3797 	}
3798 	for (i = 0; i < vm_ndomains; i++) {
3799 		if (TAILQ_EMPTY(&new_tail[i]))
3800 			continue;
3801 		pvc = &pv_chunks[i];
3802 		mtx_lock(&pvc->pvc_lock);
3803 		TAILQ_CONCAT(&pvc->pvc_list, &new_tail[i], pc_lru);
3804 		mtx_unlock(&pvc->pvc_lock);
3805 	}
3806 }
3807 
3808 /*
3809  * First find and then remove the pv entry for the specified pmap and virtual
3810  * address from the specified pv list.  Returns the pv entry if found and NULL
3811  * otherwise.  This operation can be performed on pv lists for either 4KB or
3812  * 2MB page mappings.
3813  */
3814 static __inline pv_entry_t
3815 pmap_pvh_remove(struct md_page *pvh, pmap_t pmap, vm_offset_t va)
3816 {
3817 	pv_entry_t pv;
3818 
3819 	TAILQ_FOREACH(pv, &pvh->pv_list, pv_next) {
3820 		if (pmap == PV_PMAP(pv) && va == pv->pv_va) {
3821 			TAILQ_REMOVE(&pvh->pv_list, pv, pv_next);
3822 			pvh->pv_gen++;
3823 			break;
3824 		}
3825 	}
3826 	return (pv);
3827 }
3828 
3829 /*
3830  * After demotion from a 2MB page mapping to 512 4KB page mappings,
3831  * destroy the pv entry for the 2MB page mapping and reinstantiate the pv
3832  * entries for each of the 4KB page mappings.
3833  */
3834 static void
3835 pmap_pv_demote_l2(pmap_t pmap, vm_offset_t va, vm_paddr_t pa,
3836     struct rwlock **lockp)
3837 {
3838 	struct md_page *pvh;
3839 	struct pv_chunk *pc;
3840 	pv_entry_t pv;
3841 	vm_offset_t va_last;
3842 	vm_page_t m;
3843 	int bit, field;
3844 
3845 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
3846 	KASSERT((va & L2_OFFSET) == 0,
3847 	    ("pmap_pv_demote_l2: va is not 2mpage aligned"));
3848 	KASSERT((pa & L2_OFFSET) == 0,
3849 	    ("pmap_pv_demote_l2: pa is not 2mpage aligned"));
3850 	CHANGE_PV_LIST_LOCK_TO_PHYS(lockp, pa);
3851 
3852 	/*
3853 	 * Transfer the 2mpage's pv entry for this mapping to the first
3854 	 * page's pv list.  Once this transfer begins, the pv list lock
3855 	 * must not be released until the last pv entry is reinstantiated.
3856 	 */
3857 	pvh = pa_to_pvh(pa);
3858 	pv = pmap_pvh_remove(pvh, pmap, va);
3859 	KASSERT(pv != NULL, ("pmap_pv_demote_l2: pv not found"));
3860 	m = PHYS_TO_VM_PAGE(pa);
3861 	TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_next);
3862 	m->md.pv_gen++;
3863 	/* Instantiate the remaining Ln_ENTRIES - 1 pv entries. */
3864 	PV_STAT(atomic_add_long(&pv_entry_allocs, Ln_ENTRIES - 1));
3865 	va_last = va + L2_SIZE - PAGE_SIZE;
3866 	for (;;) {
3867 		pc = TAILQ_FIRST(&pmap->pm_pvchunk);
3868 		KASSERT(!pc_is_full(pc), ("pmap_pv_demote_l2: missing spare"));
3869 		for (field = 0; field < _NPCM; field++) {
3870 			while (pc->pc_map[field]) {
3871 				bit = ffsl(pc->pc_map[field]) - 1;
3872 				pc->pc_map[field] &= ~(1ul << bit);
3873 				pv = &pc->pc_pventry[field * 64 + bit];
3874 				va += PAGE_SIZE;
3875 				pv->pv_va = va;
3876 				m++;
3877 				KASSERT((m->oflags & VPO_UNMANAGED) == 0,
3878 			    ("pmap_pv_demote_l2: page %p is not managed", m));
3879 				TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_next);
3880 				m->md.pv_gen++;
3881 				if (va == va_last)
3882 					goto out;
3883 			}
3884 		}
3885 		TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
3886 		TAILQ_INSERT_TAIL(&pmap->pm_pvchunk, pc, pc_list);
3887 	}
3888 out:
3889 	if (pc_is_full(pc)) {
3890 		TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
3891 		TAILQ_INSERT_TAIL(&pmap->pm_pvchunk, pc, pc_list);
3892 	}
3893 	PV_STAT(atomic_add_long(&pv_entry_count, Ln_ENTRIES - 1));
3894 	PV_STAT(atomic_subtract_int(&pv_entry_spare, Ln_ENTRIES - 1));
3895 }
3896 
3897 /*
3898  * First find and then destroy the pv entry for the specified pmap and virtual
3899  * address.  This operation can be performed on pv lists for either 4KB or 2MB
3900  * page mappings.
3901  */
3902 static void
3903 pmap_pvh_free(struct md_page *pvh, pmap_t pmap, vm_offset_t va)
3904 {
3905 	pv_entry_t pv;
3906 
3907 	pv = pmap_pvh_remove(pvh, pmap, va);
3908 	KASSERT(pv != NULL, ("pmap_pvh_free: pv not found"));
3909 	free_pv_entry(pmap, pv);
3910 }
3911 
3912 /*
3913  * Conditionally create the PV entry for a 4KB page mapping if the required
3914  * memory can be allocated without resorting to reclamation.
3915  */
3916 static bool
3917 pmap_try_insert_pv_entry(pmap_t pmap, vm_offset_t va, vm_page_t m,
3918     struct rwlock **lockp)
3919 {
3920 	pv_entry_t pv;
3921 
3922 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
3923 	/* Pass NULL instead of the lock pointer to disable reclamation. */
3924 	if ((pv = get_pv_entry(pmap, NULL)) != NULL) {
3925 		pv->pv_va = va;
3926 		CHANGE_PV_LIST_LOCK_TO_VM_PAGE(lockp, m);
3927 		TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_next);
3928 		m->md.pv_gen++;
3929 		return (true);
3930 	} else
3931 		return (false);
3932 }
3933 
3934 /*
3935  * Create the PV entry for a 2MB page mapping.  Always returns true unless the
3936  * flag PMAP_ENTER_NORECLAIM is specified.  If that flag is specified, returns
3937  * false if the PV entry cannot be allocated without resorting to reclamation.
3938  */
3939 static bool
3940 pmap_pv_insert_l2(pmap_t pmap, vm_offset_t va, pd_entry_t l2e, u_int flags,
3941     struct rwlock **lockp)
3942 {
3943 	struct md_page *pvh;
3944 	pv_entry_t pv;
3945 	vm_paddr_t pa;
3946 
3947 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
3948 	/* Pass NULL instead of the lock pointer to disable reclamation. */
3949 	if ((pv = get_pv_entry(pmap, (flags & PMAP_ENTER_NORECLAIM) != 0 ?
3950 	    NULL : lockp)) == NULL)
3951 		return (false);
3952 	pv->pv_va = va;
3953 	pa = PTE_TO_PHYS(l2e);
3954 	CHANGE_PV_LIST_LOCK_TO_PHYS(lockp, pa);
3955 	pvh = pa_to_pvh(pa);
3956 	TAILQ_INSERT_TAIL(&pvh->pv_list, pv, pv_next);
3957 	pvh->pv_gen++;
3958 	return (true);
3959 }
3960 
3961 /*
3962  * Conditionally creates the PV entries for a L3C superpage mapping if
3963  * the required memory can be allocated without resorting to reclamation.
3964  */
3965 static bool
3966 pmap_pv_insert_l3c(pmap_t pmap, vm_offset_t va, vm_page_t m,
3967     struct rwlock **lockp)
3968 {
3969 	pv_entry_t pv;
3970 	vm_offset_t tva;
3971 	vm_paddr_t pa __diagused;
3972 	vm_page_t mt;
3973 
3974 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
3975 	KASSERT((va & L3C_OFFSET) == 0,
3976 	    ("pmap_pv_insert_l3c: va is not aligned"));
3977 	pa = VM_PAGE_TO_PHYS(m);
3978 	KASSERT((pa & L3C_OFFSET) == 0,
3979 	    ("pmap_pv_insert_l3c: pa is not aligned"));
3980 	CHANGE_PV_LIST_LOCK_TO_VM_PAGE(lockp, m);
3981 	for (mt = m, tva = va; mt < &m[L3C_ENTRIES]; mt++, tva += L3_SIZE) {
3982 		/* Pass NULL instead of lockp to disable reclamation. */
3983 		pv = get_pv_entry(pmap, NULL);
3984 		if (__predict_false(pv == NULL)) {
3985 			while (tva > va) {
3986 				mt--;
3987 				tva -= L3_SIZE;
3988 				pmap_pvh_free(&mt->md, pmap, tva);
3989 			}
3990 			return (false);
3991 		}
3992 		pv->pv_va = tva;
3993 		TAILQ_INSERT_TAIL(&mt->md.pv_list, pv, pv_next);
3994 		mt->md.pv_gen++;
3995 	}
3996 	return (true);
3997 }
3998 
3999 static void
4000 pmap_remove_kernel_l2(pmap_t pmap, pt_entry_t *l2, vm_offset_t va)
4001 {
4002 	pt_entry_t newl2, oldl2 __diagused;
4003 	vm_page_t ml3;
4004 	vm_paddr_t ml3pa;
4005 
4006 	KASSERT(!VIRT_IN_DMAP(va), ("removing direct mapping of %#lx", va));
4007 	KASSERT(pmap == kernel_pmap, ("pmap %p is not kernel_pmap", pmap));
4008 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4009 
4010 	ml3 = pmap_remove_pt_page(pmap, va);
4011 	KASSERT(ml3 != NULL, ("pmap_remove_kernel_l2: missing pt page"));
4012 
4013 	ml3pa = VM_PAGE_TO_PHYS(ml3);
4014 	newl2 = PHYS_TO_PTE(ml3pa) | L2_TABLE;
4015 
4016 	/*
4017 	 * If this page table page was unmapped by a promotion, then it
4018 	 * contains valid mappings.  Zero it to invalidate those mappings.
4019 	 */
4020 	if (vm_page_any_valid(ml3))
4021 		pagezero(PHYS_TO_DMAP(ml3pa));
4022 
4023 	/*
4024 	 * Demote the mapping.  The caller must have already invalidated the
4025 	 * mapping (i.e., the "break" in break-before-make).
4026 	 */
4027 	oldl2 = pmap_load_store(l2, newl2);
4028 	KASSERT(oldl2 == 0, ("%s: found existing mapping at %p: %#lx",
4029 	    __func__, l2, oldl2));
4030 }
4031 
4032 /*
4033  * pmap_remove_l2: Do the things to unmap a level 2 superpage.
4034  */
4035 static int
4036 pmap_remove_l2(pmap_t pmap, pt_entry_t *l2, vm_offset_t sva, pd_entry_t l1e,
4037     bool demote_kl2e, struct spglist *free, struct rwlock **lockp)
4038 {
4039 	struct md_page *pvh;
4040 	pt_entry_t old_l2;
4041 	vm_page_t m, ml3, mt;
4042 
4043 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4044 	KASSERT((sva & L2_OFFSET) == 0, ("pmap_remove_l2: sva is not aligned"));
4045 	old_l2 = pmap_load_clear(l2);
4046 	KASSERT((old_l2 & ATTR_DESCR_MASK) == L2_BLOCK,
4047 	    ("pmap_remove_l2: L2e %lx is not a block mapping", old_l2));
4048 
4049 	/*
4050 	 * Since a promotion must break the 4KB page mappings before making
4051 	 * the 2MB page mapping, a pmap_s1_invalidate_page() suffices.
4052 	 */
4053 	pmap_s1_invalidate_page(pmap, sva, true);
4054 
4055 	if (old_l2 & ATTR_SW_WIRED)
4056 		pmap->pm_stats.wired_count -= L2_SIZE / PAGE_SIZE;
4057 	pmap_resident_count_dec(pmap, L2_SIZE / PAGE_SIZE);
4058 	if (old_l2 & ATTR_SW_MANAGED) {
4059 		m = PTE_TO_VM_PAGE(old_l2);
4060 		pvh = page_to_pvh(m);
4061 		CHANGE_PV_LIST_LOCK_TO_VM_PAGE(lockp, m);
4062 		pmap_pvh_free(pvh, pmap, sva);
4063 		for (mt = m; mt < &m[L2_SIZE / PAGE_SIZE]; mt++) {
4064 			if (pmap_pte_dirty(pmap, old_l2))
4065 				vm_page_dirty(mt);
4066 			if (old_l2 & ATTR_AF)
4067 				vm_page_aflag_set(mt, PGA_REFERENCED);
4068 			if (TAILQ_EMPTY(&mt->md.pv_list) &&
4069 			    TAILQ_EMPTY(&pvh->pv_list))
4070 				vm_page_aflag_clear(mt, PGA_WRITEABLE);
4071 		}
4072 	}
4073 	if (pmap != kernel_pmap) {
4074 		ml3 = pmap_remove_pt_page(pmap, sva);
4075 		if (ml3 != NULL) {
4076 			KASSERT(vm_page_any_valid(ml3),
4077 			    ("pmap_remove_l2: l3 page not promoted"));
4078 			pmap_resident_count_dec(pmap, 1);
4079 			KASSERT(ml3->ref_count == NL3PG,
4080 			    ("pmap_remove_l2: l3 page ref count error"));
4081 			ml3->ref_count = 0;
4082 			pmap_add_delayed_free_list(ml3, free, false);
4083 		}
4084 	} else if (demote_kl2e) {
4085 		pmap_remove_kernel_l2(pmap, l2, sva);
4086 	} else {
4087 		ml3 = vm_radix_lookup(&pmap->pm_root, pmap_l2_pindex(sva));
4088 		if (vm_page_any_valid(ml3)) {
4089 			ml3->valid = 0;
4090 			pmap_zero_page(ml3);
4091 		}
4092 	}
4093 	return (pmap_unuse_pt(pmap, sva, l1e, free));
4094 }
4095 
4096 /*
4097  * pmap_remove_l3: do the things to unmap a page in a process
4098  */
4099 static int
4100 pmap_remove_l3(pmap_t pmap, pt_entry_t *l3, vm_offset_t va,
4101     pd_entry_t l2e, struct spglist *free, struct rwlock **lockp)
4102 {
4103 	struct md_page *pvh;
4104 	pt_entry_t old_l3;
4105 	vm_page_t m;
4106 
4107 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4108 	old_l3 = pmap_load(l3);
4109 	if ((old_l3 & ATTR_CONTIGUOUS) != 0)
4110 		(void)pmap_demote_l3c(pmap, l3, va);
4111 	old_l3 = pmap_load_clear(l3);
4112 	pmap_s1_invalidate_page(pmap, va, true);
4113 	if (old_l3 & ATTR_SW_WIRED)
4114 		pmap->pm_stats.wired_count -= 1;
4115 	pmap_resident_count_dec(pmap, 1);
4116 	if (old_l3 & ATTR_SW_MANAGED) {
4117 		m = PTE_TO_VM_PAGE(old_l3);
4118 		if (pmap_pte_dirty(pmap, old_l3))
4119 			vm_page_dirty(m);
4120 		if (old_l3 & ATTR_AF)
4121 			vm_page_aflag_set(m, PGA_REFERENCED);
4122 		CHANGE_PV_LIST_LOCK_TO_VM_PAGE(lockp, m);
4123 		pmap_pvh_free(&m->md, pmap, va);
4124 		if (TAILQ_EMPTY(&m->md.pv_list) &&
4125 		    (m->flags & PG_FICTITIOUS) == 0) {
4126 			pvh = page_to_pvh(m);
4127 			if (TAILQ_EMPTY(&pvh->pv_list))
4128 				vm_page_aflag_clear(m, PGA_WRITEABLE);
4129 		}
4130 	}
4131 	return (pmap_unuse_pt(pmap, va, l2e, free));
4132 }
4133 
4134 /*
4135  * Removes the specified L3C superpage mapping.  Requests TLB invalidations
4136  * to be performed by the caller through the returned "*vap". Returns true
4137  * if the level 3 table "ml3" was unmapped and added to the spglist "free".
4138  * Otherwise, returns false.
4139  */
4140 static bool
4141 pmap_remove_l3c(pmap_t pmap, pt_entry_t *l3p, vm_offset_t va, vm_offset_t *vap,
4142     vm_offset_t va_next, vm_page_t ml3, struct spglist *free,
4143     struct rwlock **lockp)
4144 {
4145 	struct md_page *pvh;
4146 	struct rwlock *new_lock;
4147 	pt_entry_t first_l3e, l3e, *tl3p;
4148 	vm_offset_t tva;
4149 	vm_page_t m, mt;
4150 
4151 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4152 	KASSERT(((uintptr_t)l3p & ((L3C_ENTRIES * sizeof(pt_entry_t)) - 1)) ==
4153 	    0, ("pmap_remove_l3c: l3p is not aligned"));
4154 	KASSERT((va & L3C_OFFSET) == 0,
4155 	    ("pmap_remove_l3c: va is not aligned"));
4156 
4157 	/*
4158 	 * Hardware accessed and dirty bit maintenance might only update a
4159 	 * single L3 entry, so we must combine the accessed and dirty bits
4160 	 * from this entire set of contiguous L3 entries.
4161 	 */
4162 	first_l3e = pmap_load_clear(l3p);
4163 	for (tl3p = l3p + 1; tl3p < &l3p[L3C_ENTRIES]; tl3p++) {
4164 		l3e = pmap_load_clear(tl3p);
4165 		KASSERT((l3e & ATTR_CONTIGUOUS) != 0,
4166 		    ("pmap_remove_l3c: l3e is missing ATTR_CONTIGUOUS"));
4167 		if ((l3e & (ATTR_SW_DBM | ATTR_S1_AP_RW_BIT)) ==
4168 		    (ATTR_SW_DBM | ATTR_S1_AP(ATTR_S1_AP_RW)))
4169 			first_l3e &= ~ATTR_S1_AP_RW_BIT;
4170 		first_l3e |= l3e & ATTR_AF;
4171 	}
4172 	if ((first_l3e & ATTR_SW_WIRED) != 0)
4173 		pmap->pm_stats.wired_count -= L3C_ENTRIES;
4174 	pmap_resident_count_dec(pmap, L3C_ENTRIES);
4175 	if ((first_l3e & ATTR_SW_MANAGED) != 0) {
4176 		m = PTE_TO_VM_PAGE(first_l3e);
4177 		new_lock = VM_PAGE_TO_PV_LIST_LOCK(m);
4178 		if (new_lock != *lockp) {
4179 			if (*lockp != NULL) {
4180 				/*
4181 				 * Pending TLB invalidations must be
4182 				 * performed before the PV list lock is
4183 				 * released.  Otherwise, a concurrent
4184 				 * pmap_remove_all() on a physical page
4185 				 * could return while a stale TLB entry
4186 				 * still provides access to that page.
4187 				 */
4188 				if (*vap != va_next) {
4189 					pmap_invalidate_range(pmap, *vap, va,
4190 					    true);
4191 					*vap = va_next;
4192 				}
4193 				rw_wunlock(*lockp);
4194 			}
4195 			*lockp = new_lock;
4196 			rw_wlock(*lockp);
4197 		}
4198 		pvh = page_to_pvh(m);
4199 		for (mt = m, tva = va; mt < &m[L3C_ENTRIES]; mt++, tva +=
4200 		    L3_SIZE) {
4201 			if (pmap_pte_dirty(pmap, first_l3e))
4202 				vm_page_dirty(mt);
4203 			if ((first_l3e & ATTR_AF) != 0)
4204 				vm_page_aflag_set(mt, PGA_REFERENCED);
4205 			pmap_pvh_free(&mt->md, pmap, tva);
4206 			if (TAILQ_EMPTY(&mt->md.pv_list) &&
4207 			    TAILQ_EMPTY(&pvh->pv_list))
4208 				vm_page_aflag_clear(mt, PGA_WRITEABLE);
4209 		}
4210 	}
4211 	if (*vap == va_next)
4212 		*vap = va;
4213 	if (ml3 != NULL) {
4214 		ml3->ref_count -= L3C_ENTRIES;
4215 		if (ml3->ref_count == 0) {
4216 			_pmap_unwire_l3(pmap, va, ml3, free);
4217 			return (true);
4218 		}
4219 	}
4220 	return (false);
4221 }
4222 
4223 /*
4224  * Remove the specified range of addresses from the L3 page table that is
4225  * identified by the given L2 entry.
4226  */
4227 static void
4228 pmap_remove_l3_range(pmap_t pmap, pd_entry_t l2e, vm_offset_t sva,
4229     vm_offset_t eva, struct spglist *free, struct rwlock **lockp)
4230 {
4231 	struct md_page *pvh;
4232 	struct rwlock *new_lock;
4233 	pt_entry_t *l3, old_l3;
4234 	vm_offset_t va;
4235 	vm_page_t l3pg, m;
4236 
4237 	KASSERT(ADDR_IS_CANONICAL(sva),
4238 	    ("%s: Start address not in canonical form: %lx", __func__, sva));
4239 	KASSERT(ADDR_IS_CANONICAL(eva) || eva == VM_MAX_USER_ADDRESS,
4240 	    ("%s: End address not in canonical form: %lx", __func__, eva));
4241 
4242 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4243 	KASSERT(rounddown2(sva, L2_SIZE) + L2_SIZE == roundup2(eva, L2_SIZE),
4244 	    ("pmap_remove_l3_range: range crosses an L3 page table boundary"));
4245 	l3pg = ADDR_IS_USER(sva) ? PTE_TO_VM_PAGE(l2e) : NULL;
4246 	va = eva;
4247 	for (l3 = pmap_l2_to_l3(&l2e, sva); sva != eva; l3++, sva += L3_SIZE) {
4248 		old_l3 = pmap_load(l3);
4249 		if (!pmap_l3_valid(old_l3)) {
4250 			if (va != eva) {
4251 				pmap_invalidate_range(pmap, va, sva, true);
4252 				va = eva;
4253 			}
4254 			continue;
4255 		}
4256 		if ((old_l3 & ATTR_CONTIGUOUS) != 0) {
4257 			/*
4258 			 * Is this entire set of contiguous L3 entries being
4259 			 * removed?  Handle the possibility that "eva" is zero
4260 			 * because of address wraparound.
4261 			 */
4262 			if ((sva & L3C_OFFSET) == 0 &&
4263 			    sva + L3C_OFFSET <= eva - 1) {
4264 				if (pmap_remove_l3c(pmap, l3, sva, &va, eva,
4265 				    l3pg, free, lockp)) {
4266 					/* The L3 table was unmapped. */
4267 					sva += L3C_SIZE;
4268 					break;
4269 				}
4270 				l3 += L3C_ENTRIES - 1;
4271 				sva += L3C_SIZE - L3_SIZE;
4272 				continue;
4273 			}
4274 
4275 			(void)pmap_demote_l3c(pmap, l3, sva);
4276 		}
4277 		old_l3 = pmap_load_clear(l3);
4278 		if ((old_l3 & ATTR_SW_WIRED) != 0)
4279 			pmap->pm_stats.wired_count--;
4280 		pmap_resident_count_dec(pmap, 1);
4281 		/* Below will only be true in a realm environment. */
4282 		if (PTE_TO_PHYS(old_l3) & prot_ns_shared_pa)
4283 			pmap_set_protected(old_l3);
4284 		if ((old_l3 & ATTR_SW_MANAGED) != 0) {
4285 			m = PTE_TO_VM_PAGE(old_l3);
4286 			if (pmap_pte_dirty(pmap, old_l3))
4287 				vm_page_dirty(m);
4288 			if ((old_l3 & ATTR_AF) != 0)
4289 				vm_page_aflag_set(m, PGA_REFERENCED);
4290 			new_lock = VM_PAGE_TO_PV_LIST_LOCK(m);
4291 			if (new_lock != *lockp) {
4292 				if (*lockp != NULL) {
4293 					/*
4294 					 * Pending TLB invalidations must be
4295 					 * performed before the PV list lock is
4296 					 * released.  Otherwise, a concurrent
4297 					 * pmap_remove_all() on a physical page
4298 					 * could return while a stale TLB entry
4299 					 * still provides access to that page.
4300 					 */
4301 					if (va != eva) {
4302 						pmap_invalidate_range(pmap, va,
4303 						    sva, true);
4304 						va = eva;
4305 					}
4306 					rw_wunlock(*lockp);
4307 				}
4308 				*lockp = new_lock;
4309 				rw_wlock(*lockp);
4310 			}
4311 			pmap_pvh_free(&m->md, pmap, sva);
4312 			if (TAILQ_EMPTY(&m->md.pv_list) &&
4313 			    (m->flags & PG_FICTITIOUS) == 0) {
4314 				pvh = page_to_pvh(m);
4315 				if (TAILQ_EMPTY(&pvh->pv_list))
4316 					vm_page_aflag_clear(m, PGA_WRITEABLE);
4317 			}
4318 		}
4319 		if (l3pg != NULL && pmap_unwire_l3(pmap, sva, l3pg, free)) {
4320 			/*
4321 			 * _pmap_unwire_l3() has already invalidated the TLB
4322 			 * entries at all levels for "sva".  So, we need not
4323 			 * perform "sva += L3_SIZE;" here.  Moreover, we need
4324 			 * not perform "va = sva;" if "sva" is at the start
4325 			 * of a new valid range consisting of a single page.
4326 			 */
4327 			break;
4328 		}
4329 		if (va == eva)
4330 			va = sva;
4331 	}
4332 	if (va != eva)
4333 		pmap_invalidate_range(pmap, va, sva, true);
4334 }
4335 
4336 static void
4337 pmap_remove1(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, bool map_delete)
4338 {
4339 	struct rwlock *lock;
4340 	vm_offset_t va_next;
4341 	pd_entry_t *l0, *l1, *l2;
4342 	pt_entry_t l3_paddr;
4343 	struct spglist free;
4344 
4345 	/*
4346 	 * Perform an unsynchronized read.  This is, however, safe.
4347 	 */
4348 	if (pmap->pm_stats.resident_count == 0)
4349 		return;
4350 
4351 	SLIST_INIT(&free);
4352 
4353 	PMAP_LOCK(pmap);
4354 	if (map_delete)
4355 		pmap_bti_on_remove(pmap, sva, eva);
4356 
4357 	lock = NULL;
4358 	for (; sva < eva; sva = va_next) {
4359 		if (pmap->pm_stats.resident_count == 0)
4360 			break;
4361 
4362 		l0 = pmap_l0(pmap, sva);
4363 		if (pmap_load(l0) == 0) {
4364 			va_next = (sva + L0_SIZE) & ~L0_OFFSET;
4365 			if (va_next < sva)
4366 				va_next = eva;
4367 			continue;
4368 		}
4369 
4370 		va_next = (sva + L1_SIZE) & ~L1_OFFSET;
4371 		if (va_next < sva)
4372 			va_next = eva;
4373 		l1 = pmap_l0_to_l1(l0, sva);
4374 		if (pmap_load(l1) == 0)
4375 			continue;
4376 		if ((pmap_load(l1) & ATTR_DESCR_MASK) == L1_BLOCK) {
4377 			PMAP_ASSERT_L1_BLOCKS_SUPPORTED;
4378 			KASSERT(va_next <= eva,
4379 			    ("partial update of non-transparent 1G page "
4380 			    "l1 %#lx sva %#lx eva %#lx va_next %#lx",
4381 			    pmap_load(l1), sva, eva, va_next));
4382 			MPASS(pmap != kernel_pmap);
4383 			MPASS((pmap_load(l1) & ATTR_SW_MANAGED) == 0);
4384 			pmap_clear(l1);
4385 			pmap_s1_invalidate_page(pmap, sva, true);
4386 			pmap_resident_count_dec(pmap, L1_SIZE / PAGE_SIZE);
4387 			pmap_unuse_pt(pmap, sva, pmap_load(l0), &free);
4388 			continue;
4389 		}
4390 
4391 		/*
4392 		 * Calculate index for next page table.
4393 		 */
4394 		va_next = (sva + L2_SIZE) & ~L2_OFFSET;
4395 		if (va_next < sva)
4396 			va_next = eva;
4397 
4398 		l2 = pmap_l1_to_l2(l1, sva);
4399 		l3_paddr = pmap_load(l2);
4400 
4401 		if ((l3_paddr & ATTR_DESCR_MASK) == L2_BLOCK) {
4402 			if (sva + L2_SIZE == va_next && eva >= va_next) {
4403 				pmap_remove_l2(pmap, l2, sva, pmap_load(l1),
4404 				    true, &free, &lock);
4405 				continue;
4406 			} else if (pmap_demote_l2_locked(pmap, l2, sva,
4407 			    &lock) == NULL)
4408 				continue;
4409 			l3_paddr = pmap_load(l2);
4410 		}
4411 
4412 		/*
4413 		 * Weed out invalid mappings.
4414 		 */
4415 		if ((l3_paddr & ATTR_DESCR_MASK) != L2_TABLE)
4416 			continue;
4417 
4418 		/*
4419 		 * Limit our scan to either the end of the va represented
4420 		 * by the current page table page, or to the end of the
4421 		 * range being removed.
4422 		 */
4423 		if (va_next > eva)
4424 			va_next = eva;
4425 
4426 		pmap_remove_l3_range(pmap, l3_paddr, sva, va_next, &free,
4427 		    &lock);
4428 	}
4429 	if (lock != NULL)
4430 		rw_wunlock(lock);
4431 	PMAP_UNLOCK(pmap);
4432 	vm_page_free_pages_toq(&free, true);
4433 }
4434 
4435 /*
4436  *	Remove the given range of addresses from the specified map.
4437  *
4438  *	It is assumed that the start and end are properly
4439  *	rounded to the page size.
4440  */
4441 void
4442 pmap_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
4443 {
4444 	pmap_remove1(pmap, sva, eva, false);
4445 }
4446 
4447 /*
4448  *	Remove the given range of addresses as part of a logical unmap
4449  *	operation. This has the effect of calling pmap_remove(), but
4450  *	also clears any metadata that should persist for the lifetime
4451  *	of a logical mapping.
4452  */
4453 void
4454 pmap_map_delete(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
4455 {
4456 	pmap_remove1(pmap, sva, eva, true);
4457 }
4458 
4459 /*
4460  *	Routine:	pmap_remove_all
4461  *	Function:
4462  *		Removes this physical page from
4463  *		all physical maps in which it resides.
4464  *		Reflects back modify bits to the pager.
4465  *
4466  *	Notes:
4467  *		Original versions of this routine were very
4468  *		inefficient because they iteratively called
4469  *		pmap_remove (slow...)
4470  */
4471 
4472 void
4473 pmap_remove_all(vm_page_t m)
4474 {
4475 	struct md_page *pvh;
4476 	pv_entry_t pv;
4477 	pmap_t pmap;
4478 	struct rwlock *lock;
4479 	pd_entry_t *pde, tpde;
4480 	pt_entry_t *pte, tpte;
4481 	vm_offset_t va;
4482 	struct spglist free;
4483 	int lvl, pvh_gen, md_gen;
4484 
4485 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
4486 	    ("pmap_remove_all: page %p is not managed", m));
4487 	SLIST_INIT(&free);
4488 	lock = VM_PAGE_TO_PV_LIST_LOCK(m);
4489 	pvh = (m->flags & PG_FICTITIOUS) != 0 ? &pv_dummy : page_to_pvh(m);
4490 	rw_wlock(lock);
4491 retry:
4492 	while ((pv = TAILQ_FIRST(&pvh->pv_list)) != NULL) {
4493 		pmap = PV_PMAP(pv);
4494 		if (!PMAP_TRYLOCK(pmap)) {
4495 			pvh_gen = pvh->pv_gen;
4496 			rw_wunlock(lock);
4497 			PMAP_LOCK(pmap);
4498 			rw_wlock(lock);
4499 			if (pvh_gen != pvh->pv_gen) {
4500 				PMAP_UNLOCK(pmap);
4501 				goto retry;
4502 			}
4503 		}
4504 		va = pv->pv_va;
4505 		pte = pmap_pte_exists(pmap, va, 2, __func__);
4506 		pmap_demote_l2_locked(pmap, pte, va, &lock);
4507 		PMAP_UNLOCK(pmap);
4508 	}
4509 	while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) {
4510 		pmap = PV_PMAP(pv);
4511 		if (!PMAP_TRYLOCK(pmap)) {
4512 			pvh_gen = pvh->pv_gen;
4513 			md_gen = m->md.pv_gen;
4514 			rw_wunlock(lock);
4515 			PMAP_LOCK(pmap);
4516 			rw_wlock(lock);
4517 			if (pvh_gen != pvh->pv_gen || md_gen != m->md.pv_gen) {
4518 				PMAP_UNLOCK(pmap);
4519 				goto retry;
4520 			}
4521 		}
4522 		pmap_resident_count_dec(pmap, 1);
4523 
4524 		pde = pmap_pde(pmap, pv->pv_va, &lvl);
4525 		KASSERT(pde != NULL,
4526 		    ("pmap_remove_all: no page directory entry found"));
4527 		KASSERT(lvl == 2,
4528 		    ("pmap_remove_all: invalid pde level %d", lvl));
4529 		tpde = pmap_load(pde);
4530 
4531 		pte = pmap_l2_to_l3(pde, pv->pv_va);
4532 		tpte = pmap_load(pte);
4533 		if ((tpte & ATTR_CONTIGUOUS) != 0)
4534 			(void)pmap_demote_l3c(pmap, pte, pv->pv_va);
4535 		tpte = pmap_load_clear(pte);
4536 		if (tpte & ATTR_SW_WIRED)
4537 			pmap->pm_stats.wired_count--;
4538 		if ((tpte & ATTR_AF) != 0) {
4539 			pmap_invalidate_page(pmap, pv->pv_va, true);
4540 			vm_page_aflag_set(m, PGA_REFERENCED);
4541 		}
4542 
4543 		/*
4544 		 * Update the vm_page_t clean and reference bits.
4545 		 */
4546 		if (pmap_pte_dirty(pmap, tpte))
4547 			vm_page_dirty(m);
4548 		pmap_unuse_pt(pmap, pv->pv_va, tpde, &free);
4549 		TAILQ_REMOVE(&m->md.pv_list, pv, pv_next);
4550 		m->md.pv_gen++;
4551 		free_pv_entry(pmap, pv);
4552 		PMAP_UNLOCK(pmap);
4553 	}
4554 	vm_page_aflag_clear(m, PGA_WRITEABLE);
4555 	rw_wunlock(lock);
4556 	vm_page_free_pages_toq(&free, true);
4557 }
4558 
4559 /*
4560  * Masks and sets bits in a level 2 page table entries in the specified pmap
4561  */
4562 static void
4563 pmap_protect_l2(pmap_t pmap, pt_entry_t *l2, vm_offset_t sva, pt_entry_t mask,
4564     pt_entry_t nbits)
4565 {
4566 	pd_entry_t old_l2;
4567 	vm_page_t m, mt;
4568 
4569 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4570 	PMAP_ASSERT_STAGE1(pmap);
4571 	KASSERT((sva & L2_OFFSET) == 0,
4572 	    ("pmap_protect_l2: sva is not 2mpage aligned"));
4573 	old_l2 = pmap_load(l2);
4574 	KASSERT((old_l2 & ATTR_DESCR_MASK) == L2_BLOCK,
4575 	    ("pmap_protect_l2: L2e %lx is not a block mapping", old_l2));
4576 
4577 	/*
4578 	 * Return if the L2 entry already has the desired access restrictions
4579 	 * in place.
4580 	 */
4581 	if ((old_l2 & mask) == nbits)
4582 		return;
4583 
4584 	while (!atomic_fcmpset_64(l2, &old_l2, (old_l2 & ~mask) | nbits))
4585 		cpu_spinwait();
4586 
4587 	/*
4588 	 * When a dirty read/write superpage mapping is write protected,
4589 	 * update the dirty field of each of the superpage's constituent 4KB
4590 	 * pages.
4591 	 */
4592 	if ((old_l2 & ATTR_SW_MANAGED) != 0 &&
4593 	    (nbits & ATTR_S1_AP(ATTR_S1_AP_RO)) != 0 &&
4594 	    pmap_pte_dirty(pmap, old_l2)) {
4595 		m = PTE_TO_VM_PAGE(old_l2);
4596 		for (mt = m; mt < &m[L2_SIZE / PAGE_SIZE]; mt++)
4597 			vm_page_dirty(mt);
4598 	}
4599 
4600 	/*
4601 	 * Since a promotion must break the 4KB page mappings before making
4602 	 * the 2MB page mapping, a pmap_s1_invalidate_page() suffices.
4603 	 */
4604 	pmap_s1_invalidate_page(pmap, sva, true);
4605 }
4606 
4607 /*
4608  * Masks and sets bits in the specified L3C superpage mapping.
4609  *
4610  * Requests TLB invalidations to be performed by the caller through the
4611  * returned "*vap".
4612  */
4613 static void
4614 pmap_mask_set_l3c(pmap_t pmap, pt_entry_t *l3p, vm_offset_t va,
4615     vm_offset_t *vap, vm_offset_t va_next, pt_entry_t mask, pt_entry_t nbits)
4616 {
4617 	pt_entry_t l3e, *tl3p;
4618 	vm_page_t m, mt;
4619 	bool dirty;
4620 
4621 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4622 	KASSERT(((uintptr_t)l3p & ((L3C_ENTRIES * sizeof(pt_entry_t)) - 1)) ==
4623 	    0, ("pmap_mask_set_l3c: l3p is not aligned"));
4624 	KASSERT((va & L3C_OFFSET) == 0,
4625 	    ("pmap_mask_set_l3c: va is not aligned"));
4626 	dirty = false;
4627 	for (tl3p = l3p; tl3p < &l3p[L3C_ENTRIES]; tl3p++) {
4628 		l3e = pmap_load(tl3p);
4629 		KASSERT((l3e & ATTR_CONTIGUOUS) != 0,
4630 		    ("pmap_mask_set_l3c: l3e is missing ATTR_CONTIGUOUS"));
4631 		while (!atomic_fcmpset_64(tl3p, &l3e, (l3e & ~mask) | nbits))
4632 			cpu_spinwait();
4633 		if ((l3e & (ATTR_SW_DBM | ATTR_S1_AP_RW_BIT)) ==
4634 		    (ATTR_SW_DBM | ATTR_S1_AP(ATTR_S1_AP_RW)))
4635 			dirty = true;
4636 	}
4637 
4638 	/*
4639 	 * When a dirty read/write superpage mapping is write protected,
4640 	 * update the dirty field of each of the superpage's constituent 4KB
4641 	 * pages.
4642 	 */
4643 	if ((l3e & ATTR_SW_MANAGED) != 0 &&
4644 	    (nbits & ATTR_S1_AP(ATTR_S1_AP_RO)) != 0 &&
4645 	    dirty) {
4646 		m = PTE_TO_VM_PAGE(pmap_load(l3p));
4647 		for (mt = m; mt < &m[L3C_ENTRIES]; mt++)
4648 			vm_page_dirty(mt);
4649 	}
4650 
4651 	if (*vap == va_next)
4652 		*vap = va;
4653 }
4654 
4655 /*
4656  * Masks and sets bits in last level page table entries in the specified
4657  * pmap and range
4658  */
4659 static void
4660 pmap_mask_set_locked(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, pt_entry_t mask,
4661     pt_entry_t nbits, bool invalidate)
4662 {
4663 	vm_offset_t va, va_next;
4664 	pd_entry_t *l0, *l1, *l2;
4665 	pt_entry_t *l3p, l3;
4666 
4667 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4668 	for (; sva < eva; sva = va_next) {
4669 		l0 = pmap_l0(pmap, sva);
4670 		if (pmap_load(l0) == 0) {
4671 			va_next = (sva + L0_SIZE) & ~L0_OFFSET;
4672 			if (va_next < sva)
4673 				va_next = eva;
4674 			continue;
4675 		}
4676 
4677 		va_next = (sva + L1_SIZE) & ~L1_OFFSET;
4678 		if (va_next < sva)
4679 			va_next = eva;
4680 		l1 = pmap_l0_to_l1(l0, sva);
4681 		if (pmap_load(l1) == 0)
4682 			continue;
4683 		if ((pmap_load(l1) & ATTR_DESCR_MASK) == L1_BLOCK) {
4684 			PMAP_ASSERT_L1_BLOCKS_SUPPORTED;
4685 			KASSERT(va_next <= eva,
4686 			    ("partial update of non-transparent 1G page "
4687 			    "l1 %#lx sva %#lx eva %#lx va_next %#lx",
4688 			    pmap_load(l1), sva, eva, va_next));
4689 			MPASS((pmap_load(l1) & ATTR_SW_MANAGED) == 0);
4690 			if ((pmap_load(l1) & mask) != nbits) {
4691 				pmap_store(l1, (pmap_load(l1) & ~mask) | nbits);
4692 				if (invalidate)
4693 					pmap_s1_invalidate_page(pmap, sva, true);
4694 			}
4695 			continue;
4696 		}
4697 
4698 		va_next = (sva + L2_SIZE) & ~L2_OFFSET;
4699 		if (va_next < sva)
4700 			va_next = eva;
4701 
4702 		l2 = pmap_l1_to_l2(l1, sva);
4703 		if (pmap_load(l2) == 0)
4704 			continue;
4705 
4706 		if ((pmap_load(l2) & ATTR_DESCR_MASK) == L2_BLOCK) {
4707 			if (sva + L2_SIZE == va_next && eva >= va_next) {
4708 				pmap_protect_l2(pmap, l2, sva, mask, nbits);
4709 				continue;
4710 			} else if ((pmap_load(l2) & mask) == nbits ||
4711 			    pmap_demote_l2(pmap, l2, sva) == NULL)
4712 				continue;
4713 		}
4714 		KASSERT((pmap_load(l2) & ATTR_DESCR_MASK) == L2_TABLE,
4715 		    ("pmap_protect: Invalid L2 entry after demotion"));
4716 
4717 		if (va_next > eva)
4718 			va_next = eva;
4719 
4720 		va = va_next;
4721 		for (l3p = pmap_l2_to_l3(l2, sva); sva != va_next; l3p++,
4722 		    sva += L3_SIZE) {
4723 			l3 = pmap_load(l3p);
4724 
4725 			/*
4726 			 * Go to the next L3 entry if the current one is
4727 			 * invalid or already has the desired access
4728 			 * restrictions in place.  (The latter case occurs
4729 			 * frequently.  For example, in a "buildworld"
4730 			 * workload, almost 1 out of 4 L3 entries already
4731 			 * have the desired restrictions.)
4732 			 */
4733 			if (!pmap_l3_valid(l3) || (l3 & mask) == nbits) {
4734 				if (va != va_next) {
4735 					if (invalidate)
4736 						pmap_s1_invalidate_range(pmap,
4737 						    va, sva, true);
4738 					va = va_next;
4739 				}
4740 				if ((l3 & ATTR_CONTIGUOUS) != 0) {
4741 					/*
4742 					 * Does this L3C page extend beyond
4743 					 * the requested range?  Handle the
4744 					 * possibility that "va_next" is zero.
4745 					 */
4746 					if ((sva | L3C_OFFSET) > va_next - 1)
4747 						break;
4748 
4749 					/*
4750 					 * Skip ahead to the last L3_PAGE
4751 					 * within this L3C page.
4752 					 */
4753 					l3p = (pt_entry_t *)((uintptr_t)l3p |
4754 					    ((L3C_ENTRIES - 1) *
4755 					    sizeof(pt_entry_t)));
4756 					sva |= L3C_SIZE - L3_SIZE;
4757 				}
4758 				continue;
4759 			}
4760 
4761 			if ((l3 & ATTR_CONTIGUOUS) != 0) {
4762 				/*
4763 				 * Is this entire set of contiguous L3 entries
4764 				 * being protected?  Handle the possibility
4765 				 * that "va_next" is zero because of address
4766 				 * wraparound.
4767 				 */
4768 				if ((sva & L3C_OFFSET) == 0 &&
4769 				    sva + L3C_OFFSET <= va_next - 1) {
4770 					pmap_mask_set_l3c(pmap, l3p, sva, &va,
4771 					    va_next, mask, nbits);
4772 					l3p += L3C_ENTRIES - 1;
4773 					sva += L3C_SIZE - L3_SIZE;
4774 					continue;
4775 				}
4776 
4777 				(void)pmap_demote_l3c(pmap, l3p, sva);
4778 
4779 				/*
4780 				 * The L3 entry's accessed bit may have changed.
4781 				 */
4782 				l3 = pmap_load(l3p);
4783 			}
4784 			while (!atomic_fcmpset_64(l3p, &l3, (l3 & ~mask) |
4785 			    nbits))
4786 				cpu_spinwait();
4787 
4788 			/*
4789 			 * When a dirty read/write mapping is write protected,
4790 			 * update the page's dirty field.
4791 			 */
4792 			if ((l3 & ATTR_SW_MANAGED) != 0 &&
4793 			    (nbits & ATTR_S1_AP(ATTR_S1_AP_RO)) != 0 &&
4794 			    pmap_pte_dirty(pmap, l3))
4795 				vm_page_dirty(PTE_TO_VM_PAGE(l3));
4796 
4797 			if (va == va_next)
4798 				va = sva;
4799 		}
4800 		if (va != va_next && invalidate)
4801 			pmap_s1_invalidate_range(pmap, va, sva, true);
4802 	}
4803 }
4804 
4805 static void
4806 pmap_mask_set(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, pt_entry_t mask,
4807     pt_entry_t nbits, bool invalidate)
4808 {
4809 	PMAP_LOCK(pmap);
4810 	pmap_mask_set_locked(pmap, sva, eva, mask, nbits, invalidate);
4811 	PMAP_UNLOCK(pmap);
4812 }
4813 
4814 /*
4815  *	Set the physical protection on the
4816  *	specified range of this map as requested.
4817  */
4818 void
4819 pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot)
4820 {
4821 	pt_entry_t mask, nbits;
4822 
4823 	PMAP_ASSERT_STAGE1(pmap);
4824 	KASSERT((prot & ~VM_PROT_ALL) == 0, ("invalid prot %x", prot));
4825 	if (prot == VM_PROT_NONE) {
4826 		pmap_remove(pmap, sva, eva);
4827 		return;
4828 	}
4829 
4830 	mask = nbits = 0;
4831 	if ((prot & VM_PROT_WRITE) == 0) {
4832 		mask |= ATTR_S1_AP_RW_BIT | ATTR_SW_DBM;
4833 		nbits |= ATTR_S1_AP(ATTR_S1_AP_RO);
4834 	}
4835 	if ((prot & VM_PROT_EXECUTE) == 0) {
4836 		mask |= ATTR_S1_XN;
4837 		nbits |= ATTR_S1_XN;
4838 	}
4839 	if (pmap == kernel_pmap) {
4840 		mask |= ATTR_KERN_GP;
4841 		nbits |= ATTR_KERN_GP;
4842 	}
4843 	if (mask == 0)
4844 		return;
4845 
4846 	pmap_mask_set(pmap, sva, eva, mask, nbits, true);
4847 }
4848 
4849 void
4850 pmap_disable_promotion(vm_offset_t sva, vm_size_t size)
4851 {
4852 
4853 	MPASS((sva & L3_OFFSET) == 0);
4854 	MPASS(((sva + size) & L3_OFFSET) == 0);
4855 
4856 	pmap_mask_set(kernel_pmap, sva, sva + size, ATTR_SW_NO_PROMOTE,
4857 	    ATTR_SW_NO_PROMOTE, false);
4858 }
4859 
4860 /*
4861  * Inserts the specified page table page into the specified pmap's collection
4862  * of idle page table pages.  Each of a pmap's page table pages is responsible
4863  * for mapping a distinct range of virtual addresses.  The pmap's collection is
4864  * ordered by this virtual address range.
4865  *
4866  * If "promoted" is false, then the page table page "mpte" must be zero filled;
4867  * "mpte"'s valid field will be set to 0.
4868  *
4869  * If "promoted" is true and "all_l3e_AF_set" is false, then "mpte" must
4870  * contain valid mappings with identical attributes except for ATTR_AF;
4871  * "mpte"'s valid field will be set to 1.
4872  *
4873  * If "promoted" and "all_l3e_AF_set" are both true, then "mpte" must contain
4874  * valid mappings with identical attributes including ATTR_AF; "mpte"'s valid
4875  * field will be set to VM_PAGE_BITS_ALL.
4876  */
4877 static __inline int
4878 pmap_insert_pt_page(pmap_t pmap, vm_page_t mpte, bool promoted,
4879     bool all_l3e_AF_set)
4880 {
4881 
4882 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4883 	KASSERT(promoted || !all_l3e_AF_set,
4884 	    ("a zero-filled PTP can't have ATTR_AF set in every PTE"));
4885 	mpte->valid = promoted ? (all_l3e_AF_set ? VM_PAGE_BITS_ALL : 1) : 0;
4886 	return (vm_radix_insert(&pmap->pm_root, mpte));
4887 }
4888 
4889 /*
4890  * Removes the page table page mapping the specified virtual address from the
4891  * specified pmap's collection of idle page table pages, and returns it.
4892  * Otherwise, returns NULL if there is no page table page corresponding to the
4893  * specified virtual address.
4894  */
4895 static __inline vm_page_t
4896 pmap_remove_pt_page(pmap_t pmap, vm_offset_t va)
4897 {
4898 
4899 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4900 	return (vm_radix_remove(&pmap->pm_root, pmap_l2_pindex(va)));
4901 }
4902 
4903 /*
4904  * Performs a break-before-make update of a pmap entry. This is needed when
4905  * either promoting or demoting pages to ensure the TLB doesn't get into an
4906  * inconsistent state.
4907  */
4908 static void
4909 pmap_update_entry(pmap_t pmap, pd_entry_t *ptep, pd_entry_t newpte,
4910     vm_offset_t va, vm_size_t size)
4911 {
4912 	register_t intr;
4913 
4914 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4915 	KASSERT((newpte & ATTR_SW_NO_PROMOTE) == 0,
4916 	    ("%s: Updating non-promote pte", __func__));
4917 
4918 	/*
4919 	 * Ensure we don't get switched out with the page table in an
4920 	 * inconsistent state. We also need to ensure no interrupts fire
4921 	 * as they may make use of an address we are about to invalidate.
4922 	 */
4923 	intr = intr_disable();
4924 
4925 	/*
4926 	 * Clear the old mapping's valid bit, but leave the rest of the entry
4927 	 * unchanged, so that a lockless, concurrent pmap_kextract() can still
4928 	 * lookup the physical address.
4929 	 */
4930 	pmap_clear_bits(ptep, ATTR_DESCR_VALID);
4931 
4932 	/*
4933 	 * When promoting, the L{1,2}_TABLE entry that is being replaced might
4934 	 * be cached, so we invalidate intermediate entries as well as final
4935 	 * entries.
4936 	 */
4937 	pmap_s1_invalidate_range(pmap, va, va + size, false);
4938 
4939 	/* Create the new mapping */
4940 	pmap_store(ptep, newpte);
4941 	dsb(ishst);
4942 
4943 	intr_restore(intr);
4944 }
4945 
4946 /*
4947  * Performs a break-before-make update of an ATTR_CONTIGUOUS mapping.
4948  */
4949 static void __nosanitizecoverage
4950 pmap_update_strided(pmap_t pmap, pd_entry_t *ptep, pd_entry_t *ptep_end,
4951     pd_entry_t newpte, vm_offset_t va, vm_offset_t stride, vm_size_t size)
4952 {
4953 	pd_entry_t *lip;
4954 	register_t intr;
4955 
4956 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4957 	KASSERT((newpte & ATTR_SW_NO_PROMOTE) == 0,
4958 	    ("%s: Updating non-promote pte", __func__));
4959 
4960 	/*
4961 	 * Ensure we don't get switched out with the page table in an
4962 	 * inconsistent state. We also need to ensure no interrupts fire
4963 	 * as they may make use of an address we are about to invalidate.
4964 	 */
4965 	intr = intr_disable();
4966 
4967 	/*
4968 	 * Clear the old mapping's valid bits, but leave the rest of each
4969 	 * entry unchanged, so that a lockless, concurrent pmap_kextract() can
4970 	 * still lookup the physical address.
4971 	 */
4972 	for (lip = ptep; lip < ptep_end; lip++)
4973 		pmap_clear_bits(lip, ATTR_DESCR_VALID);
4974 
4975 	/* Only final entries are changing. */
4976 	pmap_s1_invalidate_strided(pmap, va, va + size, stride, true);
4977 
4978 	/* Create the new mapping. */
4979 	for (lip = ptep; lip < ptep_end; lip++) {
4980 		pmap_store(lip, newpte);
4981 		newpte += stride;
4982 	}
4983 	dsb(ishst);
4984 
4985 	intr_restore(intr);
4986 }
4987 
4988 #if VM_NRESERVLEVEL > 0
4989 /*
4990  * After promotion from 512 4KB page mappings to a single 2MB page mapping,
4991  * replace the many pv entries for the 4KB page mappings by a single pv entry
4992  * for the 2MB page mapping.
4993  */
4994 static void
4995 pmap_pv_promote_l2(pmap_t pmap, vm_offset_t va, vm_paddr_t pa,
4996     struct rwlock **lockp)
4997 {
4998 	struct md_page *pvh;
4999 	pv_entry_t pv;
5000 	vm_offset_t va_last;
5001 	vm_page_t m;
5002 
5003 	KASSERT((pa & L2_OFFSET) == 0,
5004 	    ("pmap_pv_promote_l2: pa is not 2mpage aligned"));
5005 	CHANGE_PV_LIST_LOCK_TO_PHYS(lockp, pa);
5006 
5007 	/*
5008 	 * Transfer the first page's pv entry for this mapping to the 2mpage's
5009 	 * pv list.  Aside from avoiding the cost of a call to get_pv_entry(),
5010 	 * a transfer avoids the possibility that get_pv_entry() calls
5011 	 * reclaim_pv_chunk() and that reclaim_pv_chunk() removes one of the
5012 	 * mappings that is being promoted.
5013 	 */
5014 	m = PHYS_TO_VM_PAGE(pa);
5015 	va = va & ~L2_OFFSET;
5016 	pv = pmap_pvh_remove(&m->md, pmap, va);
5017 	KASSERT(pv != NULL, ("pmap_pv_promote_l2: pv not found"));
5018 	pvh = page_to_pvh(m);
5019 	TAILQ_INSERT_TAIL(&pvh->pv_list, pv, pv_next);
5020 	pvh->pv_gen++;
5021 	/* Free the remaining NPTEPG - 1 pv entries. */
5022 	va_last = va + L2_SIZE - PAGE_SIZE;
5023 	do {
5024 		m++;
5025 		va += PAGE_SIZE;
5026 		pmap_pvh_free(&m->md, pmap, va);
5027 	} while (va < va_last);
5028 }
5029 
5030 /*
5031  * Tries to promote the 512, contiguous 4KB page mappings that are within a
5032  * single level 2 table entry to a single 2MB page mapping.  For promotion
5033  * to occur, two conditions must be met: (1) the 4KB page mappings must map
5034  * aligned, contiguous physical memory and (2) the 4KB page mappings must have
5035  * identical characteristics.
5036  */
5037 static bool
5038 pmap_promote_l2(pmap_t pmap, pd_entry_t *l2, vm_offset_t va, vm_page_t mpte,
5039     struct rwlock **lockp)
5040 {
5041 	pt_entry_t all_l3e_AF, *firstl3, *l3, newl2, oldl3, pa;
5042 
5043 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
5044 
5045 	/*
5046 	 * Currently, this function only supports promotion on stage 1 pmaps
5047 	 * because it tests stage 1 specific fields and performs a break-
5048 	 * before-make sequence that is incorrect for stage 2 pmaps.
5049 	 */
5050 	if (pmap->pm_stage != PM_STAGE1 || !pmap_ps_enabled(pmap))
5051 		return (false);
5052 
5053 	/*
5054 	 * Examine the first L3E in the specified PTP.  Abort if this L3E is
5055 	 * ineligible for promotion...
5056 	 */
5057 	firstl3 = PHYS_TO_DMAP(PTE_TO_PHYS(pmap_load(l2)));
5058 	newl2 = pmap_load(firstl3);
5059 	if ((newl2 & ATTR_SW_NO_PROMOTE) != 0)
5060 		return (false);
5061 	/* ... is not the first physical page within an L2 block */
5062 	if ((PTE_TO_PHYS(newl2) & L2_OFFSET) != 0 ||
5063 	    ((newl2 & ATTR_DESCR_MASK) != L3_PAGE)) { /* ... or is invalid */
5064 		counter_u64_add(pmap_l2_p_failures, 1);
5065 		CTR2(KTR_PMAP, "pmap_promote_l2: failure for va %#lx"
5066 		    " in pmap %p", va, pmap);
5067 		return (false);
5068 	}
5069 
5070 	/*
5071 	 * Both here and in the below "for" loop, to allow for repromotion
5072 	 * after MADV_FREE, conditionally write protect a clean L3E before
5073 	 * possibly aborting the promotion due to other L3E attributes.  Why?
5074 	 * Suppose that MADV_FREE is applied to a part of a superpage, the
5075 	 * address range [S, E).  pmap_advise() will demote the superpage
5076 	 * mapping, destroy the 4KB page mapping at the end of [S, E), and
5077 	 * set AP_RO and clear AF in the L3Es for the rest of [S, E).  Later,
5078 	 * imagine that the memory in [S, E) is recycled, but the last 4KB
5079 	 * page in [S, E) is not the last to be rewritten, or simply accessed.
5080 	 * In other words, there is still a 4KB page in [S, E), call it P,
5081 	 * that is writeable but AP_RO is set and AF is clear in P's L3E.
5082 	 * Unless we write protect P before aborting the promotion, if and
5083 	 * when P is finally rewritten, there won't be a page fault to trigger
5084 	 * repromotion.
5085 	 */
5086 setl2:
5087 	if ((newl2 & (ATTR_S1_AP_RW_BIT | ATTR_SW_DBM)) ==
5088 	    (ATTR_S1_AP(ATTR_S1_AP_RO) | ATTR_SW_DBM)) {
5089 		/*
5090 		 * When the mapping is clean, i.e., ATTR_S1_AP_RO is set,
5091 		 * ATTR_SW_DBM can be cleared without a TLB invalidation.
5092 		 */
5093 		if (!atomic_fcmpset_64(firstl3, &newl2, newl2 & ~ATTR_SW_DBM))
5094 			goto setl2;
5095 		newl2 &= ~ATTR_SW_DBM;
5096 		CTR2(KTR_PMAP, "pmap_promote_l2: protect for va %#lx"
5097 		    " in pmap %p", va & ~L2_OFFSET, pmap);
5098 	}
5099 
5100 	/*
5101 	 * Examine each of the other L3Es in the specified PTP.  Abort if this
5102 	 * L3E maps an unexpected 4KB physical page or does not have identical
5103 	 * characteristics to the first L3E.  If ATTR_AF is not set in every
5104 	 * PTE, then request that the PTP be refilled on demotion.
5105 	 */
5106 	all_l3e_AF = newl2 & ATTR_AF;
5107 	pa = (PTE_TO_PHYS(newl2) | (newl2 & ATTR_DESCR_MASK))
5108 	    + L2_SIZE - PAGE_SIZE;
5109 	for (l3 = firstl3 + NL3PG - 1; l3 > firstl3; l3--) {
5110 		oldl3 = pmap_load(l3);
5111 		if ((PTE_TO_PHYS(oldl3) | (oldl3 & ATTR_DESCR_MASK)) != pa) {
5112 			counter_u64_add(pmap_l2_p_failures, 1);
5113 			CTR2(KTR_PMAP, "pmap_promote_l2: failure for va %#lx"
5114 			    " in pmap %p", va, pmap);
5115 			return (false);
5116 		}
5117 setl3:
5118 		if ((oldl3 & (ATTR_S1_AP_RW_BIT | ATTR_SW_DBM)) ==
5119 		    (ATTR_S1_AP(ATTR_S1_AP_RO) | ATTR_SW_DBM)) {
5120 			/*
5121 			 * When the mapping is clean, i.e., ATTR_S1_AP_RO is
5122 			 * set, ATTR_SW_DBM can be cleared without a TLB
5123 			 * invalidation.
5124 			 */
5125 			if (!atomic_fcmpset_64(l3, &oldl3, oldl3 &
5126 			    ~ATTR_SW_DBM))
5127 				goto setl3;
5128 			oldl3 &= ~ATTR_SW_DBM;
5129 		}
5130 		if ((oldl3 & ATTR_PROMOTE) != (newl2 & ATTR_PROMOTE)) {
5131 			counter_u64_add(pmap_l2_p_failures, 1);
5132 			CTR2(KTR_PMAP, "pmap_promote_l2: failure for va %#lx"
5133 			    " in pmap %p", va, pmap);
5134 			return (false);
5135 		}
5136 		all_l3e_AF &= oldl3;
5137 		pa -= PAGE_SIZE;
5138 	}
5139 
5140 	/*
5141 	 * Unless all PTEs have ATTR_AF set, clear it from the superpage
5142 	 * mapping, so that promotions triggered by speculative mappings,
5143 	 * such as pmap_enter_quick(), don't automatically mark the
5144 	 * underlying pages as referenced.
5145 	 */
5146 	newl2 &= ~(ATTR_CONTIGUOUS | ATTR_AF | ATTR_DESCR_MASK) | all_l3e_AF;
5147 
5148 	/*
5149 	 * Save the page table page in its current state until the L2
5150 	 * mapping the superpage is demoted by pmap_demote_l2() or
5151 	 * destroyed by pmap_remove_l3().
5152 	 */
5153 	if (mpte == NULL)
5154 		mpte = PTE_TO_VM_PAGE(pmap_load(l2));
5155 	KASSERT(mpte >= vm_page_array &&
5156 	    mpte < &vm_page_array[vm_page_array_size],
5157 	    ("pmap_promote_l2: page table page is out of range"));
5158 	KASSERT(mpte->pindex == pmap_l2_pindex(va),
5159 	    ("pmap_promote_l2: page table page's pindex is wrong"));
5160 	if (pmap_insert_pt_page(pmap, mpte, true, all_l3e_AF != 0)) {
5161 		counter_u64_add(pmap_l2_p_failures, 1);
5162 		CTR2(KTR_PMAP,
5163 		    "pmap_promote_l2: failure for va %#lx in pmap %p", va,
5164 		    pmap);
5165 		return (false);
5166 	}
5167 
5168 	if ((newl2 & ATTR_SW_MANAGED) != 0)
5169 		pmap_pv_promote_l2(pmap, va, PTE_TO_PHYS(newl2), lockp);
5170 
5171 	pmap_update_entry(pmap, l2, newl2 | L2_BLOCK, va & ~L2_OFFSET, L2_SIZE);
5172 
5173 	counter_u64_add(pmap_l2_promotions, 1);
5174 	CTR2(KTR_PMAP, "pmap_promote_l2: success for va %#lx in pmap %p", va,
5175 	    pmap);
5176 	return (true);
5177 }
5178 
5179 /*
5180  * Tries to promote an aligned, contiguous set of base page mappings to a
5181  * single L3C page mapping.  For promotion to occur, two conditions must be
5182  * met: (1) the base page mappings must map aligned, contiguous physical
5183  * memory and (2) the base page mappings must have identical characteristics
5184  * except for the accessed flag.
5185  */
5186 static bool
5187 pmap_promote_l3c(pmap_t pmap, pd_entry_t *l3p, vm_offset_t va)
5188 {
5189 	pd_entry_t all_l3e_AF, firstl3c, *l3, oldl3, pa;
5190 
5191 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
5192 
5193 	/*
5194 	 * Currently, this function only supports promotion on stage 1 pmaps
5195 	 * because it tests stage 1 specific fields and performs a break-
5196 	 * before-make sequence that is incorrect for stage 2 pmaps.
5197 	 */
5198 	if (pmap->pm_stage != PM_STAGE1 || !pmap_ps_enabled(pmap))
5199 		return (false);
5200 
5201 	/*
5202 	 * Compute the address of the first L3 entry in the superpage
5203 	 * candidate.
5204 	 */
5205 	l3p = (pt_entry_t *)((uintptr_t)l3p & ~((L3C_ENTRIES *
5206 	    sizeof(pt_entry_t)) - 1));
5207 
5208 	firstl3c = pmap_load(l3p);
5209 
5210 	/*
5211 	 * Examine the first L3 entry. Abort if this L3E is ineligible for
5212 	 * promotion...
5213 	 */
5214 	if ((firstl3c & ATTR_SW_NO_PROMOTE) != 0)
5215 		return (false);
5216 	/* ...is not properly aligned... */
5217 	if ((PTE_TO_PHYS(firstl3c) & L3C_OFFSET) != 0 ||
5218 	    (firstl3c & ATTR_DESCR_MASK) != L3_PAGE) { /* ...or is invalid. */
5219 		counter_u64_add(pmap_l3c_p_failures, 1);
5220 		CTR2(KTR_PMAP, "pmap_promote_l3c: failure for va %#lx"
5221 		    " in pmap %p", va, pmap);
5222 		return (false);
5223 	}
5224 
5225 	/*
5226 	 * If the first L3 entry is a clean read-write mapping, convert it
5227 	 * to a read-only mapping.  See pmap_promote_l2() for the rationale.
5228 	 */
5229 set_first:
5230 	if ((firstl3c & (ATTR_S1_AP_RW_BIT | ATTR_SW_DBM)) ==
5231 	    (ATTR_S1_AP(ATTR_S1_AP_RO) | ATTR_SW_DBM)) {
5232 		/*
5233 		 * When the mapping is clean, i.e., ATTR_S1_AP_RO is set,
5234 		 * ATTR_SW_DBM can be cleared without a TLB invalidation.
5235 		 */
5236 		if (!atomic_fcmpset_64(l3p, &firstl3c, firstl3c & ~ATTR_SW_DBM))
5237 			goto set_first;
5238 		firstl3c &= ~ATTR_SW_DBM;
5239 		CTR2(KTR_PMAP, "pmap_promote_l3c: protect for va %#lx"
5240 		    " in pmap %p", va & ~L3C_OFFSET, pmap);
5241 	}
5242 
5243 	/*
5244 	 * Check that the rest of the L3 entries are compatible with the first,
5245 	 * and convert clean read-write mappings to read-only mappings.
5246 	 */
5247 	all_l3e_AF = firstl3c & ATTR_AF;
5248 	pa = (PTE_TO_PHYS(firstl3c) | (firstl3c & ATTR_DESCR_MASK)) +
5249 	    L3C_SIZE - PAGE_SIZE;
5250 	for (l3 = l3p + L3C_ENTRIES - 1; l3 > l3p; l3--) {
5251 		oldl3 = pmap_load(l3);
5252 		if ((PTE_TO_PHYS(oldl3) | (oldl3 & ATTR_DESCR_MASK)) != pa) {
5253 			counter_u64_add(pmap_l3c_p_failures, 1);
5254 			CTR2(KTR_PMAP, "pmap_promote_l3c: failure for va %#lx"
5255 			    " in pmap %p", va, pmap);
5256 			return (false);
5257 		}
5258 set_l3:
5259 		if ((oldl3 & (ATTR_S1_AP_RW_BIT | ATTR_SW_DBM)) ==
5260 		    (ATTR_S1_AP(ATTR_S1_AP_RO) | ATTR_SW_DBM)) {
5261 			/*
5262 			 * When the mapping is clean, i.e., ATTR_S1_AP_RO is
5263 			 * set, ATTR_SW_DBM can be cleared without a TLB
5264 			 * invalidation.
5265 			 */
5266 			if (!atomic_fcmpset_64(l3, &oldl3, oldl3 &
5267 			    ~ATTR_SW_DBM))
5268 				goto set_l3;
5269 			oldl3 &= ~ATTR_SW_DBM;
5270 			CTR2(KTR_PMAP, "pmap_promote_l3c: protect for va %#lx"
5271 			    " in pmap %p", (oldl3 & ~ATTR_MASK & L3C_OFFSET) |
5272 			    (va & ~L3C_OFFSET), pmap);
5273 		}
5274 		if ((oldl3 & ATTR_PROMOTE) != (firstl3c & ATTR_PROMOTE)) {
5275 			counter_u64_add(pmap_l3c_p_failures, 1);
5276 			CTR2(KTR_PMAP, "pmap_promote_l3c: failure for va %#lx"
5277 			    " in pmap %p", va, pmap);
5278 			return (false);
5279 		}
5280 		all_l3e_AF &= oldl3;
5281 		pa -= PAGE_SIZE;
5282 	}
5283 
5284 	/*
5285 	 * Unless all PTEs have ATTR_AF set, clear it from the superpage
5286 	 * mapping, so that promotions triggered by speculative mappings,
5287 	 * such as pmap_enter_quick(), don't automatically mark the
5288 	 * underlying pages as referenced.
5289 	 */
5290 	firstl3c &= ~ATTR_AF | all_l3e_AF;
5291 
5292 	/*
5293 	 * Remake the mappings with the contiguous bit set.
5294 	 */
5295 	pmap_update_strided(pmap, l3p, l3p + L3C_ENTRIES, firstl3c |
5296 	    ATTR_CONTIGUOUS, va & ~L3C_OFFSET, L3_SIZE, L3C_SIZE);
5297 
5298 	counter_u64_add(pmap_l3c_promotions, 1);
5299 	CTR2(KTR_PMAP, "pmap_promote_l3c: success for va %#lx in pmap %p", va,
5300 	    pmap);
5301 	return (true);
5302 }
5303 #endif /* VM_NRESERVLEVEL > 0 */
5304 
5305 static int
5306 pmap_enter_largepage(pmap_t pmap, vm_offset_t va, pt_entry_t pte, int flags,
5307     int psind)
5308 {
5309 	pd_entry_t *l0p, *l1p, *l2p, *l3p, newpte, origpte, *tl3p;
5310 	vm_page_t mp;
5311 
5312 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
5313 	KASSERT(psind > 0 && psind < MAXPAGESIZES,
5314 	    ("psind %d unexpected", psind));
5315 	KASSERT((PTE_TO_PHYS(pte) & (pagesizes[psind] - 1)) == 0,
5316 	    ("unaligned phys address %#lx pte %#lx psind %d",
5317 	    PTE_TO_PHYS(pte), pte, psind));
5318 
5319 restart:
5320 	newpte = pte;
5321 	if (!pmap_bti_same(pmap, va, va + pagesizes[psind], &newpte))
5322 		return (KERN_PROTECTION_FAILURE);
5323 	if (psind == 3) {
5324 		PMAP_ASSERT_L1_BLOCKS_SUPPORTED;
5325 
5326 		KASSERT(pagesizes[psind] == L1_SIZE,
5327 		    ("pagesizes[%d] != L1_SIZE", psind));
5328 		l0p = pmap_l0(pmap, va);
5329 		if ((pmap_load(l0p) & ATTR_DESCR_VALID) == 0) {
5330 			mp = _pmap_alloc_l3(pmap, pmap_l0_pindex(va), NULL);
5331 			if (mp == NULL) {
5332 				if ((flags & PMAP_ENTER_NOSLEEP) != 0)
5333 					return (KERN_RESOURCE_SHORTAGE);
5334 				PMAP_UNLOCK(pmap);
5335 				vm_wait(NULL);
5336 				PMAP_LOCK(pmap);
5337 				goto restart;
5338 			}
5339 			l1p = pmap_l0_to_l1(l0p, va);
5340 			KASSERT(l1p != NULL, ("va %#lx lost l1 entry", va));
5341 			origpte = pmap_load(l1p);
5342 		} else {
5343 			l1p = pmap_l0_to_l1(l0p, va);
5344 			KASSERT(l1p != NULL, ("va %#lx lost l1 entry", va));
5345 			origpte = pmap_load(l1p);
5346 			if ((origpte & ATTR_DESCR_VALID) == 0) {
5347 				mp = PTE_TO_VM_PAGE(pmap_load(l0p));
5348 				mp->ref_count++;
5349 			}
5350 		}
5351 		KASSERT((PTE_TO_PHYS(origpte) == PTE_TO_PHYS(newpte) &&
5352 		    (origpte & ATTR_DESCR_MASK) == L1_BLOCK) ||
5353 		    (origpte & ATTR_DESCR_VALID) == 0,
5354 		    ("va %#lx changing 1G phys page l1 %#lx newpte %#lx",
5355 		    va, origpte, newpte));
5356 		pmap_store(l1p, newpte);
5357 	} else if (psind == 2) {
5358 		KASSERT(pagesizes[psind] == L2_SIZE,
5359 		    ("pagesizes[%d] != L2_SIZE", psind));
5360 		l2p = pmap_l2(pmap, va);
5361 		if (l2p == NULL) {
5362 			mp = _pmap_alloc_l3(pmap, pmap_l1_pindex(va), NULL);
5363 			if (mp == NULL) {
5364 				if ((flags & PMAP_ENTER_NOSLEEP) != 0)
5365 					return (KERN_RESOURCE_SHORTAGE);
5366 				PMAP_UNLOCK(pmap);
5367 				vm_wait(NULL);
5368 				PMAP_LOCK(pmap);
5369 				goto restart;
5370 			}
5371 			l2p = VM_PAGE_TO_DMAP(mp);
5372 			l2p = &l2p[pmap_l2_index(va)];
5373 			origpte = pmap_load(l2p);
5374 		} else {
5375 			l1p = pmap_l1(pmap, va);
5376 			origpte = pmap_load(l2p);
5377 			if ((origpte & ATTR_DESCR_VALID) == 0) {
5378 				mp = PTE_TO_VM_PAGE(pmap_load(l1p));
5379 				mp->ref_count++;
5380 			}
5381 		}
5382 		KASSERT((origpte & ATTR_DESCR_VALID) == 0 ||
5383 		    ((origpte & ATTR_DESCR_MASK) == L2_BLOCK &&
5384 		    PTE_TO_PHYS(origpte) == PTE_TO_PHYS(newpte)),
5385 		    ("va %#lx changing 2M phys page l2 %#lx newpte %#lx",
5386 		    va, origpte, newpte));
5387 		pmap_store(l2p, newpte);
5388 	} else /* (psind == 1) */ {
5389 		KASSERT(pagesizes[psind] == L3C_SIZE,
5390 		    ("pagesizes[%d] != L3C_SIZE", psind));
5391 		l2p = pmap_l2(pmap, va);
5392 		if (l2p == NULL || (pmap_load(l2p) & ATTR_DESCR_VALID) == 0) {
5393 			mp = _pmap_alloc_l3(pmap, pmap_l2_pindex(va), NULL);
5394 			if (mp == NULL) {
5395 				if ((flags & PMAP_ENTER_NOSLEEP) != 0)
5396 					return (KERN_RESOURCE_SHORTAGE);
5397 				PMAP_UNLOCK(pmap);
5398 				vm_wait(NULL);
5399 				PMAP_LOCK(pmap);
5400 				goto restart;
5401 			}
5402 			mp->ref_count += L3C_ENTRIES - 1;
5403 			l3p = VM_PAGE_TO_DMAP(mp);
5404 			l3p = &l3p[pmap_l3_index(va)];
5405 		} else {
5406 			l3p = pmap_l2_to_l3(l2p, va);
5407 			if ((pmap_load(l3p) & ATTR_DESCR_VALID) == 0) {
5408 				mp = PTE_TO_VM_PAGE(pmap_load(l2p));
5409 				mp->ref_count += L3C_ENTRIES;
5410 			}
5411 		}
5412 		for (tl3p = l3p; tl3p < &l3p[L3C_ENTRIES]; tl3p++) {
5413 			origpte = pmap_load(tl3p);
5414 			KASSERT((origpte & ATTR_DESCR_VALID) == 0 ||
5415 			    ((origpte & ATTR_CONTIGUOUS) != 0 &&
5416 			    PTE_TO_PHYS(origpte) == PTE_TO_PHYS(newpte)),
5417 			    ("va %#lx changing 64K phys page l3 %#lx newpte %#lx",
5418 			    va, origpte, newpte));
5419 			pmap_store(tl3p, newpte);
5420 			newpte += L3_SIZE;
5421 		}
5422 	}
5423 	dsb(ishst);
5424 
5425 	if ((origpte & ATTR_DESCR_VALID) == 0)
5426 		pmap_resident_count_inc(pmap, pagesizes[psind] / PAGE_SIZE);
5427 	if ((newpte & ATTR_SW_WIRED) != 0 && (origpte & ATTR_SW_WIRED) == 0)
5428 		pmap->pm_stats.wired_count += pagesizes[psind] / PAGE_SIZE;
5429 	else if ((newpte & ATTR_SW_WIRED) == 0 &&
5430 	    (origpte & ATTR_SW_WIRED) != 0)
5431 		pmap->pm_stats.wired_count -= pagesizes[psind] / PAGE_SIZE;
5432 
5433 	return (KERN_SUCCESS);
5434 }
5435 
5436 static void
5437 pmap_set_unprotected(pt_entry_t new_l3)
5438 {
5439 	vm_paddr_t pa;
5440 
5441 	pa = PTE_TO_PHYS(new_l3) & ~prot_ns_shared_pa;
5442 
5443 	rsi_set_addr_range_state(pa, pa + L3_SIZE, RSI_RIPAS_EMPTY,
5444 	    RSI_CHANGE_DESTROYED, NULL);
5445 }
5446 
5447 static void
5448 pmap_set_protected(pt_entry_t old_l3)
5449 {
5450 	vm_paddr_t pa;
5451 
5452 	pa = PTE_TO_PHYS(old_l3) & ~prot_ns_shared_pa;
5453 
5454 	rsi_set_addr_range_state(pa, pa + L3_SIZE, RSI_RIPAS_RAM,
5455 	    RSI_CHANGE_DESTROYED, NULL);
5456 }
5457 
5458 /*
5459  *	Insert the given physical page (p) at
5460  *	the specified virtual address (v) in the
5461  *	target physical map with the protection requested.
5462  *
5463  *	If specified, the page will be wired down, meaning
5464  *	that the related pte can not be reclaimed.
5465  *
5466  *	NB:  This is the only routine which MAY NOT lazy-evaluate
5467  *	or lose information.  That is, this routine must actually
5468  *	insert this page into the given map NOW.
5469  */
5470 int
5471 pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot,
5472     u_int flags, int8_t psind)
5473 {
5474 	struct rwlock *lock;
5475 	pd_entry_t *pde;
5476 	pt_entry_t new_l3, orig_l3;
5477 	pt_entry_t *l2, *l3;
5478 	pv_entry_t pv;
5479 	vm_paddr_t opa, pa;
5480 	vm_page_t mpte, om;
5481 	bool nosleep;
5482 	int full_lvl, lvl, rv;
5483 
5484 	KASSERT(ADDR_IS_CANONICAL(va),
5485 	    ("%s: Address not in canonical form: %lx", __func__, va));
5486 
5487 	va = trunc_page(va);
5488 	if ((m->oflags & VPO_UNMANAGED) == 0)
5489 		VM_PAGE_OBJECT_BUSY_ASSERT(m);
5490 	pa = VM_PAGE_TO_PHYS(m);
5491 	if (in_realm() && (flags & PMAP_ENTER_UNPROTECTED) != 0)
5492 		pa |= prot_ns_shared_pa;
5493 	new_l3 = (pt_entry_t)(PHYS_TO_PTE(pa) | ATTR_AF | pmap_sh_attr |
5494 	    L3_PAGE);
5495 	new_l3 |= pmap_pte_memattr(pmap, m->md.pv_memattr);
5496 	new_l3 |= pmap_pte_prot(pmap, prot);
5497 	if ((flags & PMAP_ENTER_WIRED) != 0)
5498 		new_l3 |= ATTR_SW_WIRED;
5499 	if (pmap->pm_stage == PM_STAGE1) {
5500 		if (ADDR_IS_USER(va))
5501 			new_l3 |= ATTR_S1_AP(ATTR_S1_AP_USER) | ATTR_S1_PXN;
5502 		else
5503 			new_l3 |= ATTR_S1_UXN;
5504 		if (pmap != kernel_pmap)
5505 			new_l3 |= ATTR_S1_nG;
5506 	} else {
5507 		/*
5508 		 * Clear the access flag on executable mappings, this will be
5509 		 * set later when the page is accessed. The fault handler is
5510 		 * required to invalidate the I-cache.
5511 		 *
5512 		 * TODO: Switch to the valid flag to allow hardware management
5513 		 * of the access flag. Much of the pmap code assumes the
5514 		 * valid flag is set and fails to destroy the old page tables
5515 		 * correctly if it is clear.
5516 		 */
5517 		if (prot & VM_PROT_EXECUTE)
5518 			new_l3 &= ~ATTR_AF;
5519 	}
5520 	if ((m->oflags & VPO_UNMANAGED) == 0) {
5521 		new_l3 |= ATTR_SW_MANAGED;
5522 		if ((prot & VM_PROT_WRITE) != 0) {
5523 			new_l3 |= ATTR_SW_DBM;
5524 			if ((flags & VM_PROT_WRITE) == 0) {
5525 				if (pmap->pm_stage == PM_STAGE1)
5526 					new_l3 |= ATTR_S1_AP(ATTR_S1_AP_RO);
5527 				else
5528 					new_l3 &=
5529 					    ~ATTR_S2_S2AP(ATTR_S2_S2AP_WRITE);
5530 			}
5531 		}
5532 	}
5533 
5534 	CTR2(KTR_PMAP, "pmap_enter: %.16lx -> %.16lx", va, pa);
5535 
5536 	lock = NULL;
5537 	PMAP_LOCK(pmap);
5538 	if ((flags & PMAP_ENTER_LARGEPAGE) != 0) {
5539 		KASSERT((m->oflags & VPO_UNMANAGED) != 0,
5540 		    ("managed largepage va %#lx flags %#x", va, flags));
5541 		if (psind == 3) {
5542 			PMAP_ASSERT_L1_BLOCKS_SUPPORTED;
5543 			new_l3 &= ~L3_PAGE;
5544 			new_l3 |= L1_BLOCK;
5545 		} else if (psind == 2) {
5546 			new_l3 &= ~L3_PAGE;
5547 			new_l3 |= L2_BLOCK;
5548 		} else /* (psind == 1) */
5549 			new_l3 |= ATTR_CONTIGUOUS;
5550 		rv = pmap_enter_largepage(pmap, va, new_l3, flags, psind);
5551 		goto out;
5552 	}
5553 	if (psind == 2) {
5554 		/* Assert the required virtual and physical alignment. */
5555 		KASSERT((va & L2_OFFSET) == 0, ("pmap_enter: va unaligned"));
5556 		KASSERT(m->psind > 1, ("pmap_enter: m->psind < psind"));
5557 		rv = pmap_enter_l2(pmap, va, (new_l3 & ~L3_PAGE) | L2_BLOCK,
5558 		    flags, m, &lock);
5559 		goto out;
5560 	}
5561 	mpte = NULL;
5562 	if (psind == 1) {
5563 		KASSERT((va & L3C_OFFSET) == 0, ("pmap_enter: va unaligned"));
5564 		KASSERT(m->psind > 0, ("pmap_enter: m->psind < psind"));
5565 		rv = pmap_enter_l3c(pmap, va, new_l3 | ATTR_CONTIGUOUS, flags,
5566 		    m, &mpte, &lock);
5567 #if VM_NRESERVLEVEL > 0
5568 		/*
5569 		 * Attempt L2 promotion, if both the PTP and a level 1
5570 		 * reservation are fully populated.
5571 		 */
5572 		if (rv == KERN_SUCCESS &&
5573 		    (mpte == NULL || mpte->ref_count == NL3PG) &&
5574 		    (m->flags & PG_FICTITIOUS) == 0 &&
5575 		    vm_reserv_level_iffullpop(m) == 1) {
5576 			pde = pmap_l2(pmap, va);
5577 			(void)pmap_promote_l2(pmap, pde, va, mpte, &lock);
5578 		}
5579 #endif
5580 		goto out;
5581 	}
5582 
5583 	/*
5584 	 * In the case that a page table page is not
5585 	 * resident, we are creating it here.
5586 	 */
5587 retry:
5588 	pde = pmap_pde(pmap, va, &lvl);
5589 	if (pde != NULL && lvl == 2) {
5590 		l3 = pmap_l2_to_l3(pde, va);
5591 		if (ADDR_IS_USER(va) && mpte == NULL) {
5592 			mpte = PTE_TO_VM_PAGE(pmap_load(pde));
5593 			mpte->ref_count++;
5594 		}
5595 		goto havel3;
5596 	} else if (pde != NULL && lvl == 1) {
5597 		l2 = pmap_l1_to_l2(pde, va);
5598 		if ((pmap_load(l2) & ATTR_DESCR_MASK) == L2_BLOCK &&
5599 		    (l3 = pmap_demote_l2_locked(pmap, l2, va, &lock)) != NULL) {
5600 			l3 = &l3[pmap_l3_index(va)];
5601 			if (ADDR_IS_USER(va)) {
5602 				mpte = PTE_TO_VM_PAGE(pmap_load(l2));
5603 				mpte->ref_count++;
5604 			}
5605 			goto havel3;
5606 		}
5607 		/* We need to allocate an L3 table. */
5608 	}
5609 	if (ADDR_IS_USER(va)) {
5610 		nosleep = (flags & PMAP_ENTER_NOSLEEP) != 0;
5611 
5612 		/*
5613 		 * We use _pmap_alloc_l3() instead of pmap_alloc_l3() in order
5614 		 * to handle the possibility that a superpage mapping for "va"
5615 		 * was created while we slept.
5616 		 */
5617 		mpte = _pmap_alloc_l3(pmap, pmap_l2_pindex(va),
5618 		    nosleep ? NULL : &lock);
5619 		if (mpte == NULL && nosleep) {
5620 			CTR0(KTR_PMAP, "pmap_enter: mpte == NULL");
5621 			rv = KERN_RESOURCE_SHORTAGE;
5622 			goto out;
5623 		}
5624 		goto retry;
5625 	} else
5626 		panic("pmap_enter: missing L3 table for kernel va %#lx", va);
5627 
5628 havel3:
5629 	orig_l3 = pmap_load(l3);
5630 	opa = PTE_TO_PHYS(orig_l3);
5631 	pv = NULL;
5632 	new_l3 |= pmap_pte_bti(pmap, va);
5633 
5634 	/*
5635 	 * Is the specified virtual address already mapped?
5636 	 */
5637 	if (pmap_l3_valid(orig_l3)) {
5638 		/*
5639 		 * Wiring change, just update stats. We don't worry about
5640 		 * wiring PT pages as they remain resident as long as there
5641 		 * are valid mappings in them. Hence, if a user page is wired,
5642 		 * the PT page will be also.
5643 		 */
5644 		if ((flags & PMAP_ENTER_WIRED) != 0 &&
5645 		    (orig_l3 & ATTR_SW_WIRED) == 0)
5646 			pmap->pm_stats.wired_count++;
5647 		else if ((flags & PMAP_ENTER_WIRED) == 0 &&
5648 		    (orig_l3 & ATTR_SW_WIRED) != 0)
5649 			pmap->pm_stats.wired_count--;
5650 
5651 		/*
5652 		 * Remove the extra PT page reference.
5653 		 */
5654 		if (mpte != NULL) {
5655 			mpte->ref_count--;
5656 			KASSERT(mpte->ref_count > 0,
5657 			    ("pmap_enter: missing reference to page table page,"
5658 			     " va: 0x%lx", va));
5659 		}
5660 
5661 		/*
5662 		 * Has the physical page changed?
5663 		 */
5664 		if (opa == pa) {
5665 			/*
5666 			 * No, might be a protection or wiring change.
5667 			 */
5668 			if ((orig_l3 & ATTR_SW_MANAGED) != 0 &&
5669 			    (new_l3 & ATTR_SW_DBM) != 0)
5670 				vm_page_aflag_set(m, PGA_WRITEABLE);
5671 			goto validate;
5672 		}
5673 
5674 		/*
5675 		 * The physical page has changed.  Temporarily invalidate
5676 		 * the mapping.
5677 		 */
5678 		if ((orig_l3 & ATTR_CONTIGUOUS) != 0)
5679 			(void)pmap_demote_l3c(pmap, l3, va);
5680 		orig_l3 = pmap_load_clear(l3);
5681 		KASSERT(PTE_TO_PHYS(orig_l3) == opa,
5682 		    ("pmap_enter: unexpected pa update for %#lx", va));
5683 		if ((orig_l3 & ATTR_SW_MANAGED) != 0) {
5684 			om = PHYS_TO_VM_PAGE(opa);
5685 
5686 			/*
5687 			 * The pmap lock is sufficient to synchronize with
5688 			 * concurrent calls to pmap_page_test_mappings() and
5689 			 * pmap_ts_referenced().
5690 			 */
5691 			if (pmap_pte_dirty(pmap, orig_l3))
5692 				vm_page_dirty(om);
5693 			if ((orig_l3 & ATTR_AF) != 0) {
5694 				pmap_invalidate_page(pmap, va, true);
5695 				vm_page_aflag_set(om, PGA_REFERENCED);
5696 			}
5697 			CHANGE_PV_LIST_LOCK_TO_VM_PAGE(&lock, om);
5698 			pv = pmap_pvh_remove(&om->md, pmap, va);
5699 			if ((m->oflags & VPO_UNMANAGED) != 0)
5700 				free_pv_entry(pmap, pv);
5701 			if ((om->a.flags & PGA_WRITEABLE) != 0 &&
5702 			    TAILQ_EMPTY(&om->md.pv_list) &&
5703 			    ((om->flags & PG_FICTITIOUS) != 0 ||
5704 			    TAILQ_EMPTY(&page_to_pvh(om)->pv_list)))
5705 				vm_page_aflag_clear(om, PGA_WRITEABLE);
5706 		} else {
5707 			KASSERT((orig_l3 & ATTR_AF) != 0,
5708 			    ("pmap_enter: unmanaged mapping lacks ATTR_AF"));
5709 			pmap_invalidate_page(pmap, va, true);
5710 		}
5711 		orig_l3 = 0;
5712 	} else {
5713 		/*
5714 		 * Increment the counters.
5715 		 */
5716 		if ((new_l3 & ATTR_SW_WIRED) != 0)
5717 			pmap->pm_stats.wired_count++;
5718 		pmap_resident_count_inc(pmap, 1);
5719 	}
5720 	/*
5721 	 * Enter on the PV list if part of our managed memory.
5722 	 */
5723 	if ((m->oflags & VPO_UNMANAGED) == 0) {
5724 		if (pv == NULL) {
5725 			pv = get_pv_entry(pmap, &lock);
5726 			pv->pv_va = va;
5727 		}
5728 		CHANGE_PV_LIST_LOCK_TO_VM_PAGE(&lock, m);
5729 		TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_next);
5730 		m->md.pv_gen++;
5731 		if ((new_l3 & ATTR_SW_DBM) != 0)
5732 			vm_page_aflag_set(m, PGA_WRITEABLE);
5733 	}
5734 
5735 validate:
5736 	if (pmap->pm_stage == PM_STAGE1) {
5737 		/*
5738 		 * Sync icache if exec permission and attribute
5739 		 * VM_MEMATTR_WRITE_BACK is set. Do it now, before the mapping
5740 		 * is stored and made valid for hardware table walk. If done
5741 		 * later, then other can access this page before caches are
5742 		 * properly synced. Don't do it for kernel memory which is
5743 		 * mapped with exec permission even if the memory isn't going
5744 		 * to hold executable code. The only time when icache sync is
5745 		 * needed is after kernel module is loaded and the relocation
5746 		 * info is processed. And it's done in elf_cpu_load_file().
5747 		*/
5748 		if ((prot & VM_PROT_EXECUTE) &&  pmap != kernel_pmap &&
5749 		    m->md.pv_memattr == VM_MEMATTR_WRITE_BACK &&
5750 		    (opa != pa || (orig_l3 & ATTR_S1_XN))) {
5751 			PMAP_ASSERT_STAGE1(pmap);
5752 			cpu_icache_sync_range(PHYS_TO_DMAP(pa), PAGE_SIZE);
5753 		}
5754 	} else {
5755 		cpu_dcache_wb_range(PHYS_TO_DMAP(pa), PAGE_SIZE);
5756 	}
5757 
5758 	/*
5759 	 * Update the L3 entry
5760 	 */
5761 	if (pmap_l3_valid(orig_l3)) {
5762 		KASSERT(opa == pa, ("pmap_enter: invalid update"));
5763 		if ((orig_l3 & ~ATTR_AF) != (new_l3 & ~ATTR_AF)) {
5764 			/* same PA, different attributes */
5765 			if ((orig_l3 & ATTR_CONTIGUOUS) != 0)
5766 				(void)pmap_demote_l3c(pmap, l3, va);
5767 			orig_l3 = pmap_load_store(l3, new_l3);
5768 			pmap_invalidate_page(pmap, va, true);
5769 			if ((orig_l3 & ATTR_SW_MANAGED) != 0 &&
5770 			    pmap_pte_dirty(pmap, orig_l3))
5771 				vm_page_dirty(m);
5772 		} else {
5773 			/*
5774 			 * orig_l3 == new_l3
5775 			 * This can happens if multiple threads simultaneously
5776 			 * access not yet mapped page. This bad for performance
5777 			 * since this can cause full demotion-NOP-promotion
5778 			 * cycle.
5779 			 * Another possible reasons are:
5780 			 * - VM and pmap memory layout are diverged
5781 			 * - tlb flush is missing somewhere and CPU doesn't see
5782 			 *   actual mapping.
5783 			 */
5784 			CTR4(KTR_PMAP, "%s: already mapped page - "
5785 			    "pmap %p va 0x%#lx pte 0x%lx",
5786 			    __func__, pmap, va, new_l3);
5787 		}
5788 	} else {
5789 		/* New mapping */
5790 		pmap_store(l3, new_l3);
5791 		dsb(ishst);
5792 	}
5793 
5794 #if VM_NRESERVLEVEL > 0
5795 	/*
5796 	 * First, attempt L3C promotion, if the virtual and physical addresses
5797 	 * are aligned with each other and an underlying reservation has the
5798 	 * neighboring L3 pages allocated.  The first condition is simply an
5799 	 * optimization that recognizes some eventual promotion failures early
5800 	 * at a lower run-time cost.  Then, if both a level 1 reservation and
5801 	 * the PTP are fully populated, attempt L2 promotion.
5802 	 */
5803 	if ((va & L3C_OFFSET) == (pa & L3C_OFFSET) &&
5804 	    (m->flags & PG_FICTITIOUS) == 0 &&
5805 	    (full_lvl = vm_reserv_level_iffullpop(m)) >= 0 &&
5806 	    pmap_promote_l3c(pmap, l3, va) &&
5807 	    full_lvl == 1 && (mpte == NULL || mpte->ref_count == NL3PG))
5808 		(void)pmap_promote_l2(pmap, pde, va, mpte, &lock);
5809 #endif
5810 
5811 	rv = KERN_SUCCESS;
5812 
5813 	if (in_realm() && (flags & PMAP_ENTER_UNPROTECTED) != 0)
5814 		pmap_set_unprotected(new_l3);
5815 
5816 out:
5817 	if (lock != NULL)
5818 		rw_wunlock(lock);
5819 	PMAP_UNLOCK(pmap);
5820 	return (rv);
5821 }
5822 
5823 /*
5824  * Tries to create a read- and/or execute-only L2 page mapping.  Returns
5825  * KERN_SUCCESS if the mapping was created.  Otherwise, returns an error
5826  * value.  See pmap_enter_l2() for the possible error values when "no sleep",
5827  * "no replace", and "no reclaim" are specified.
5828  */
5829 static int
5830 pmap_enter_l2_rx(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot,
5831     struct rwlock **lockp)
5832 {
5833 	pd_entry_t new_l2;
5834 
5835 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
5836 	PMAP_ASSERT_STAGE1(pmap);
5837 	KASSERT(ADDR_IS_CANONICAL(va),
5838 	    ("%s: Address not in canonical form: %lx", __func__, va));
5839 
5840 	new_l2 = (pd_entry_t)(VM_PAGE_TO_PTE(m) | pmap_sh_attr |
5841 	    ATTR_S1_IDX(m->md.pv_memattr) | ATTR_S1_AP(ATTR_S1_AP_RO) |
5842 	    L2_BLOCK);
5843 	if ((m->oflags & VPO_UNMANAGED) == 0)
5844 		new_l2 |= ATTR_SW_MANAGED;
5845 	else
5846 		new_l2 |= ATTR_AF;
5847 	if ((prot & VM_PROT_EXECUTE) == 0 ||
5848 	    m->md.pv_memattr == VM_MEMATTR_DEVICE)
5849 		new_l2 |= ATTR_S1_XN;
5850 	if (ADDR_IS_USER(va))
5851 		new_l2 |= ATTR_S1_AP(ATTR_S1_AP_USER) | ATTR_S1_PXN;
5852 	else
5853 		new_l2 |= ATTR_S1_UXN;
5854 	if (pmap != kernel_pmap)
5855 		new_l2 |= ATTR_S1_nG;
5856 	return (pmap_enter_l2(pmap, va, new_l2, PMAP_ENTER_NOSLEEP |
5857 	    PMAP_ENTER_NOREPLACE | PMAP_ENTER_NORECLAIM, m, lockp));
5858 }
5859 
5860 /*
5861  * Returns true if every page table entry in the specified page table is
5862  * zero.
5863  */
5864 static bool
5865 pmap_every_pte_zero(vm_paddr_t pa)
5866 {
5867 	pt_entry_t *pt_end, *pte;
5868 
5869 	KASSERT((pa & PAGE_MASK) == 0, ("pa is misaligned"));
5870 	pte = PHYS_TO_DMAP(pa);
5871 	for (pt_end = pte + Ln_ENTRIES; pte < pt_end; pte++) {
5872 		if (*pte != 0)
5873 			return (false);
5874 	}
5875 	return (true);
5876 }
5877 
5878 /*
5879  * Tries to create the specified L2 page mapping.  Returns KERN_SUCCESS if
5880  * the mapping was created, and one of KERN_FAILURE, KERN_NO_SPACE, or
5881  * KERN_RESOURCE_SHORTAGE otherwise.  Returns KERN_FAILURE if
5882  * PMAP_ENTER_NOREPLACE was specified and a base page mapping already exists
5883  * within the L2 virtual address range starting at the specified virtual
5884  * address.  Returns KERN_NO_SPACE if PMAP_ENTER_NOREPLACE was specified and a
5885  * L2 page mapping already exists at the specified virtual address.  Returns
5886  * KERN_RESOURCE_SHORTAGE if either (1) PMAP_ENTER_NOSLEEP was specified and a
5887  * page table page allocation failed or (2) PMAP_ENTER_NORECLAIM was specified
5888  * and a PV entry allocation failed.
5889  */
5890 static int
5891 pmap_enter_l2(pmap_t pmap, vm_offset_t va, pd_entry_t new_l2, u_int flags,
5892     vm_page_t m, struct rwlock **lockp)
5893 {
5894 	struct spglist free;
5895 	pd_entry_t *l2, old_l2;
5896 	vm_page_t l2pg, mt;
5897 	vm_page_t uwptpg;
5898 
5899 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
5900 	KASSERT(ADDR_IS_CANONICAL(va),
5901 	    ("%s: Address not in canonical form: %lx", __func__, va));
5902 	KASSERT((flags & (PMAP_ENTER_NOREPLACE | PMAP_ENTER_NORECLAIM)) !=
5903 	    PMAP_ENTER_NORECLAIM,
5904 	    ("pmap_enter_l2: flags is missing PMAP_ENTER_NOREPLACE"));
5905 
5906 	if ((l2 = pmap_alloc_l2(pmap, va, &l2pg, (flags &
5907 	    PMAP_ENTER_NOSLEEP) != 0 ? NULL : lockp)) == NULL) {
5908 		CTR2(KTR_PMAP, "pmap_enter_l2: failure for va %#lx in pmap %p",
5909 		    va, pmap);
5910 		return (KERN_RESOURCE_SHORTAGE);
5911 	}
5912 
5913 	/*
5914 	 * If bti is not the same for the whole l2 range, return failure
5915 	 * and let vm_fault() cope.  Check after l2 allocation, since
5916 	 * it could sleep.
5917 	 */
5918 	if (!pmap_bti_same(pmap, va, va + L2_SIZE, &new_l2)) {
5919 		KASSERT(l2pg != NULL, ("pmap_enter_l2: missing L2 PTP"));
5920 		pmap_abort_ptp(pmap, va, l2pg);
5921 		return (KERN_PROTECTION_FAILURE);
5922 	}
5923 
5924 	/*
5925 	 * If there are existing mappings, either abort or remove them.
5926 	 */
5927 	if ((old_l2 = pmap_load(l2)) != 0) {
5928 		KASSERT(l2pg == NULL || l2pg->ref_count > 1,
5929 		    ("pmap_enter_l2: l2pg's ref count is too low"));
5930 		if ((flags & PMAP_ENTER_NOREPLACE) != 0) {
5931 			if ((old_l2 & ATTR_DESCR_MASK) == L2_BLOCK) {
5932 				if (l2pg != NULL)
5933 					l2pg->ref_count--;
5934 				CTR2(KTR_PMAP,
5935 				    "pmap_enter_l2: no space for va %#lx"
5936 				    " in pmap %p", va, pmap);
5937 				return (KERN_NO_SPACE);
5938 			} else if (ADDR_IS_USER(va) ||
5939 			    !pmap_every_pte_zero(PTE_TO_PHYS(old_l2))) {
5940 				if (l2pg != NULL)
5941 					l2pg->ref_count--;
5942 				CTR2(KTR_PMAP,
5943 				    "pmap_enter_l2: failure for va %#lx"
5944 				    " in pmap %p", va, pmap);
5945 				return (KERN_FAILURE);
5946 			}
5947 		}
5948 		SLIST_INIT(&free);
5949 		if ((old_l2 & ATTR_DESCR_MASK) == L2_BLOCK) {
5950 			(void)pmap_remove_l2(pmap, l2, va,
5951 			    pmap_load(pmap_l1(pmap, va)), false, &free, lockp);
5952 		} else {
5953 			if (ADDR_IS_KERNEL(va)) {
5954 				/*
5955 				 * Try to save the ptp in the trie
5956 				 * before any changes to mappings are
5957 				 * made.  Abort on failure.
5958 				 */
5959 				mt = PTE_TO_VM_PAGE(old_l2);
5960 				if (pmap_insert_pt_page(pmap, mt, false,
5961 				    false)) {
5962 					CTR1(KTR_PMAP,
5963 			    "pmap_enter_l2: cannot ins kern ptp va %#lx",
5964 					    va);
5965 					return (KERN_RESOURCE_SHORTAGE);
5966 				}
5967 				/*
5968 				 * Both pmap_remove_l2() and
5969 				 * pmap_remove_l3_range() will zero fill
5970 				 * the L3 kernel page table page.
5971 				 */
5972 			}
5973 			pmap_remove_l3_range(pmap, old_l2, va, va + L2_SIZE,
5974 			    &free, lockp);
5975 			if (ADDR_IS_KERNEL(va)) {
5976 				/*
5977 				 * The TLB could have an intermediate
5978 				 * entry for the L3 kernel page table
5979 				 * page, so request an invalidation at
5980 				 * all levels after clearing the
5981 				 * L2_TABLE entry.
5982 				 */
5983 				pmap_clear(l2);
5984 				pmap_s1_invalidate_page(pmap, va, false);
5985 			}
5986 		}
5987 		KASSERT(pmap_load(l2) == 0,
5988 		    ("pmap_enter_l2: non-zero L2 entry %p", l2));
5989 		if (ADDR_IS_USER(va)) {
5990 			vm_page_free_pages_toq(&free, true);
5991 		} else {
5992 			KASSERT(SLIST_EMPTY(&free),
5993 			    ("pmap_enter_l2: freed kernel page table page"));
5994 		}
5995 	}
5996 
5997 	/*
5998 	 * Allocate leaf ptpage for wired userspace pages.
5999 	 */
6000 	uwptpg = NULL;
6001 	if ((new_l2 & ATTR_SW_WIRED) != 0 && pmap != kernel_pmap) {
6002 		uwptpg = vm_page_alloc_noobj(VM_ALLOC_WIRED);
6003 		if (uwptpg == NULL) {
6004 			pmap_abort_ptp(pmap, va, l2pg);
6005 			return (KERN_RESOURCE_SHORTAGE);
6006 		}
6007 		uwptpg->pindex = pmap_l2_pindex(va);
6008 		if (pmap_insert_pt_page(pmap, uwptpg, true, false)) {
6009 			vm_page_unwire_noq(uwptpg);
6010 			vm_page_free(uwptpg);
6011 			pmap_abort_ptp(pmap, va, l2pg);
6012 			return (KERN_RESOURCE_SHORTAGE);
6013 		}
6014 		pmap_resident_count_inc(pmap, 1);
6015 		uwptpg->ref_count = NL3PG;
6016 	}
6017 	if ((new_l2 & ATTR_SW_MANAGED) != 0) {
6018 		/*
6019 		 * Abort this mapping if its PV entry could not be created.
6020 		 */
6021 		if (!pmap_pv_insert_l2(pmap, va, new_l2, flags, lockp)) {
6022 			if (l2pg != NULL)
6023 				pmap_abort_ptp(pmap, va, l2pg);
6024 			else {
6025 				KASSERT(ADDR_IS_KERNEL(va) &&
6026 				    (pmap_load(l2) & ATTR_DESCR_MASK) ==
6027 				    L2_TABLE,
6028 				    ("pmap_enter_l2: invalid kernel L2E"));
6029 				mt = pmap_remove_pt_page(pmap, va);
6030 				KASSERT(mt != NULL,
6031 				    ("pmap_enter_l2: missing kernel PTP"));
6032 			}
6033 			if (uwptpg != NULL) {
6034 				mt = pmap_remove_pt_page(pmap, va);
6035 				KASSERT(mt == uwptpg,
6036 				    ("removed pt page %p, expected %p", mt,
6037 				    uwptpg));
6038 				pmap_resident_count_dec(pmap, 1);
6039 				uwptpg->ref_count = 1;
6040 				vm_page_unwire_noq(uwptpg);
6041 				vm_page_free(uwptpg);
6042 			}
6043 			CTR2(KTR_PMAP,
6044 			    "pmap_enter_l2: failure for va %#lx in pmap %p",
6045 			    va, pmap);
6046 			return (KERN_RESOURCE_SHORTAGE);
6047 		}
6048 		if ((new_l2 & ATTR_SW_DBM) != 0)
6049 			for (mt = m; mt < &m[L2_SIZE / PAGE_SIZE]; mt++)
6050 				vm_page_aflag_set(mt, PGA_WRITEABLE);
6051 	}
6052 
6053 	/*
6054 	 * Increment counters.
6055 	 */
6056 	if ((new_l2 & ATTR_SW_WIRED) != 0)
6057 		pmap->pm_stats.wired_count += L2_SIZE / PAGE_SIZE;
6058 	pmap->pm_stats.resident_count += L2_SIZE / PAGE_SIZE;
6059 
6060 	/*
6061 	 * Conditionally sync the icache.  See pmap_enter() for details.
6062 	 */
6063 	if ((new_l2 & ATTR_S1_XN) == 0 && (PTE_TO_PHYS(new_l2) !=
6064 	    PTE_TO_PHYS(old_l2) || (old_l2 & ATTR_S1_XN) != 0) &&
6065 	    pmap != kernel_pmap && m->md.pv_memattr == VM_MEMATTR_WRITE_BACK) {
6066 		cpu_icache_sync_range(PHYS_TO_DMAP(PTE_TO_PHYS(new_l2)),
6067 		    L2_SIZE);
6068 	}
6069 
6070 	/*
6071 	 * Map the superpage.
6072 	 */
6073 	pmap_store(l2, new_l2);
6074 	dsb(ishst);
6075 
6076 	counter_u64_add(pmap_l2_mappings, 1);
6077 	CTR2(KTR_PMAP, "pmap_enter_l2: success for va %#lx in pmap %p",
6078 	    va, pmap);
6079 
6080 	return (KERN_SUCCESS);
6081 }
6082 
6083 /*
6084  * Tries to create a read- and/or execute-only L3C page mapping.  Returns
6085  * KERN_SUCCESS if the mapping was created.  Otherwise, returns an error
6086  * value.
6087  */
6088 static int
6089 pmap_enter_l3c_rx(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_page_t *ml3p,
6090     vm_prot_t prot, struct rwlock **lockp)
6091 {
6092 	pt_entry_t l3e;
6093 
6094 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
6095 	PMAP_ASSERT_STAGE1(pmap);
6096 	KASSERT(ADDR_IS_CANONICAL(va),
6097 	    ("%s: Address not in canonical form: %lx", __func__, va));
6098 
6099 	l3e = VM_PAGE_TO_PTE(m) | pmap_sh_attr |
6100 	    ATTR_S1_IDX(m->md.pv_memattr) | ATTR_S1_AP(ATTR_S1_AP_RO) |
6101 	    ATTR_CONTIGUOUS | L3_PAGE;
6102 	if ((m->oflags & VPO_UNMANAGED) == 0)
6103 		l3e |= ATTR_SW_MANAGED;
6104 	else
6105 		l3e |= ATTR_AF;
6106 	if ((prot & VM_PROT_EXECUTE) == 0 ||
6107 	    m->md.pv_memattr == VM_MEMATTR_DEVICE)
6108 		l3e |= ATTR_S1_XN;
6109 	if (ADDR_IS_USER(va))
6110 		l3e |= ATTR_S1_AP(ATTR_S1_AP_USER) | ATTR_S1_PXN;
6111 	else
6112 		l3e |= ATTR_S1_UXN;
6113 	if (pmap != kernel_pmap)
6114 		l3e |= ATTR_S1_nG;
6115 	return (pmap_enter_l3c(pmap, va, l3e, PMAP_ENTER_NOSLEEP |
6116 	    PMAP_ENTER_NOREPLACE | PMAP_ENTER_NORECLAIM, m, ml3p, lockp));
6117 }
6118 
6119 static int
6120 pmap_enter_l3c(pmap_t pmap, vm_offset_t va, pt_entry_t l3e, u_int flags,
6121     vm_page_t m, vm_page_t *ml3p, struct rwlock **lockp)
6122 {
6123 	pd_entry_t *l2p, *pde;
6124 	pt_entry_t *l3p, *tl3p;
6125 	vm_page_t mt;
6126 	vm_paddr_t pa;
6127 	vm_pindex_t l2pindex;
6128 	int lvl;
6129 
6130 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
6131 	KASSERT((va & L3C_OFFSET) == 0,
6132 	    ("pmap_enter_l3c: va is not aligned"));
6133 	KASSERT(!VA_IS_CLEANMAP(va) || (l3e & ATTR_SW_MANAGED) == 0,
6134 	    ("pmap_enter_l3c: managed mapping within the clean submap"));
6135 	KASSERT((l3e & ATTR_CONTIGUOUS) != 0,
6136 	    ("pmap_enter_l3c: l3e is missing ATTR_CONTIGUOUS"));
6137 
6138 	/*
6139 	 * If the L3 PTP is not resident, we attempt to create it here.
6140 	 */
6141 	if (ADDR_IS_USER(va)) {
6142 		/*
6143 		 * Were we given the correct L3 PTP?  If so, we can simply
6144 		 * increment its ref count.
6145 		 */
6146 		l2pindex = pmap_l2_pindex(va);
6147 		if (*ml3p != NULL && (*ml3p)->pindex == l2pindex) {
6148 			(*ml3p)->ref_count += L3C_ENTRIES;
6149 		} else {
6150 retry:
6151 			/*
6152 			 * Get the L2 entry.
6153 			 */
6154 			pde = pmap_pde(pmap, va, &lvl);
6155 
6156 			/*
6157 			 * If the L2 entry is a superpage, we either abort or
6158 			 * demote depending on the given flags.
6159 			 */
6160 			if (lvl == 1) {
6161 				l2p = pmap_l1_to_l2(pde, va);
6162 				if ((pmap_load(l2p) & ATTR_DESCR_MASK) ==
6163 				    L2_BLOCK) {
6164 					if ((flags & PMAP_ENTER_NOREPLACE) != 0)
6165 						return (KERN_FAILURE);
6166 					l3p = pmap_demote_l2_locked(pmap, l2p,
6167 					    va, lockp);
6168 					if (l3p != NULL) {
6169 						*ml3p = PTE_TO_VM_PAGE(
6170 						    pmap_load(l2p));
6171 						(*ml3p)->ref_count +=
6172 						    L3C_ENTRIES;
6173 						goto have_l3p;
6174 					}
6175 				}
6176 				/* We need to allocate an L3 PTP. */
6177 			}
6178 
6179 			/*
6180 			 * If the L3 PTP is mapped, we just increment its ref
6181 			 * count.  Otherwise, we attempt to allocate it.
6182 			 */
6183 			if (lvl == 2 && pmap_load(pde) != 0) {
6184 				*ml3p = PTE_TO_VM_PAGE(pmap_load(pde));
6185 				(*ml3p)->ref_count += L3C_ENTRIES;
6186 			} else {
6187 				*ml3p = _pmap_alloc_l3(pmap, l2pindex, (flags &
6188 				    PMAP_ENTER_NOSLEEP) != 0 ? NULL : lockp);
6189 				if (*ml3p == NULL) {
6190 					if ((flags & PMAP_ENTER_NOSLEEP) != 0)
6191 						return (KERN_FAILURE);
6192 
6193 					/*
6194 					 * The page table may have changed
6195 					 * while we slept.
6196 					 */
6197 					goto retry;
6198 				}
6199 				(*ml3p)->ref_count += L3C_ENTRIES - 1;
6200 			}
6201 		}
6202 		l3p = VM_PAGE_TO_DMAP(*ml3p);
6203 	} else {
6204 		*ml3p = NULL;
6205 
6206 		/*
6207 		 * If the L2 entry is a superpage, we either abort or demote
6208 		 * depending on the given flags.
6209 		 */
6210 		pde = pmap_pde(kernel_pmap, va, &lvl);
6211 		if (lvl == 1) {
6212 			l2p = pmap_l1_to_l2(pde, va);
6213 			KASSERT((pmap_load(l2p) & ATTR_DESCR_MASK) == L2_BLOCK,
6214 			    ("pmap_enter_l3c: missing L2 block"));
6215 			if ((flags & PMAP_ENTER_NOREPLACE) != 0)
6216 				return (KERN_FAILURE);
6217 			l3p = pmap_demote_l2_locked(pmap, l2p, va, lockp);
6218 		} else {
6219 			KASSERT(lvl == 2,
6220 			    ("pmap_enter_l3c: Invalid level %d", lvl));
6221 			l3p = PHYS_TO_DMAP(PTE_TO_PHYS(pmap_load(pde)));
6222 		}
6223 	}
6224 have_l3p:
6225 	l3p = &l3p[pmap_l3_index(va)];
6226 
6227 	/*
6228 	 * If bti is not the same for the whole L3C range, return failure
6229 	 * and let vm_fault() cope.  Check after L3 allocation, since
6230 	 * it could sleep.
6231 	 */
6232 	if (!pmap_bti_same(pmap, va, va + L3C_SIZE, &l3e)) {
6233 		KASSERT(*ml3p != NULL, ("pmap_enter_l3c: missing L3 PTP"));
6234 		(*ml3p)->ref_count -= L3C_ENTRIES - 1;
6235 		pmap_abort_ptp(pmap, va, *ml3p);
6236 		*ml3p = NULL;
6237 		return (KERN_PROTECTION_FAILURE);
6238 	}
6239 
6240 	/*
6241 	 * If there are existing mappings, either abort or remove them.
6242 	 */
6243 	if ((flags & PMAP_ENTER_NOREPLACE) != 0) {
6244 		for (tl3p = l3p; tl3p < &l3p[L3C_ENTRIES]; tl3p++) {
6245 			if (pmap_load(tl3p) != 0) {
6246 				if (*ml3p != NULL)
6247 					(*ml3p)->ref_count -= L3C_ENTRIES;
6248 				return (KERN_FAILURE);
6249 			}
6250 		}
6251 	} else {
6252 		/*
6253 		 * Because we increment the L3 page's reference count above,
6254 		 * it is guaranteed not to be freed here and we can pass NULL
6255 		 * instead of a valid free list.
6256 		 */
6257 		pmap_remove_l3_range(pmap, pmap_load(pmap_l2(pmap, va)), va,
6258 		    va + L3C_SIZE, NULL, lockp);
6259 	}
6260 
6261 	/*
6262 	 * Enter on the PV list if part of our managed memory.
6263 	 */
6264 	if ((l3e & ATTR_SW_MANAGED) != 0) {
6265 		if (!pmap_pv_insert_l3c(pmap, va, m, lockp)) {
6266 			if (*ml3p != NULL) {
6267 				(*ml3p)->ref_count -= L3C_ENTRIES - 1;
6268 				pmap_abort_ptp(pmap, va, *ml3p);
6269 				*ml3p = NULL;
6270 			}
6271 			return (KERN_RESOURCE_SHORTAGE);
6272 		}
6273 		if ((l3e & ATTR_SW_DBM) != 0)
6274 			for (mt = m; mt < &m[L3C_ENTRIES]; mt++)
6275 				vm_page_aflag_set(mt, PGA_WRITEABLE);
6276 	}
6277 
6278 	/*
6279 	 * Increment counters.
6280 	 */
6281 	if ((l3e & ATTR_SW_WIRED) != 0)
6282 		pmap->pm_stats.wired_count += L3C_ENTRIES;
6283 	pmap_resident_count_inc(pmap, L3C_ENTRIES);
6284 
6285 	pa = VM_PAGE_TO_PHYS(m);
6286 	KASSERT((pa & L3C_OFFSET) == 0, ("pmap_enter_l3c: pa is not aligned"));
6287 
6288 	/*
6289 	 * Sync the icache before the mapping is stored.
6290 	 */
6291 	if ((l3e & ATTR_S1_XN) == 0 && pmap != kernel_pmap &&
6292 	    m->md.pv_memattr == VM_MEMATTR_WRITE_BACK)
6293 		cpu_icache_sync_range(PHYS_TO_DMAP(pa), L3C_SIZE);
6294 
6295 	/*
6296 	 * Map the superpage.
6297 	 */
6298 	for (tl3p = l3p; tl3p < &l3p[L3C_ENTRIES]; tl3p++) {
6299 		pmap_store(tl3p, l3e);
6300 		l3e += L3_SIZE;
6301 	}
6302 	dsb(ishst);
6303 
6304 	counter_u64_add(pmap_l3c_mappings, 1);
6305 	CTR2(KTR_PMAP, "pmap_enter_l3c: success for va %#lx in pmap %p",
6306 	    va, pmap);
6307 	return (KERN_SUCCESS);
6308 }
6309 
6310 /*
6311  * Maps a sequence of resident pages belonging to the same object.
6312  * The sequence begins with the given page m_start.  This page is
6313  * mapped at the given virtual address start.  Each subsequent page is
6314  * mapped at a virtual address that is offset from start by the same
6315  * amount as the page is offset from m_start within the object.  The
6316  * last page in the sequence is the page with the largest offset from
6317  * m_start that can be mapped at a virtual address less than the given
6318  * virtual address end.  Not every virtual page between start and end
6319  * is mapped; only those for which a resident page exists with the
6320  * corresponding offset from m_start are mapped.
6321  */
6322 void
6323 pmap_enter_object(pmap_t pmap, vm_offset_t start, vm_offset_t end,
6324     vm_page_t m_start, vm_prot_t prot)
6325 {
6326 	struct pctrie_iter pages;
6327 	struct rwlock *lock;
6328 	vm_offset_t va;
6329 	vm_page_t m, mpte;
6330 	int rv;
6331 
6332 	VM_OBJECT_ASSERT_LOCKED(m_start->object);
6333 
6334 	mpte = NULL;
6335 	vm_page_iter_limit_init(&pages, m_start->object,
6336 	    m_start->pindex + atop(end - start));
6337 	m = vm_radix_iter_lookup(&pages, m_start->pindex);
6338 	lock = NULL;
6339 	PMAP_LOCK(pmap);
6340 	while (m != NULL) {
6341 		va = start + ptoa(m->pindex - m_start->pindex);
6342 		if ((va & L2_OFFSET) == 0 && va + L2_SIZE <= end &&
6343 		    m->psind == 2 && pmap_ps_enabled(pmap) &&
6344 		    ((rv = pmap_enter_l2_rx(pmap, va, m, prot, &lock)) ==
6345 		    KERN_SUCCESS || rv == KERN_NO_SPACE)) {
6346 			m = vm_radix_iter_jump(&pages, L2_SIZE / PAGE_SIZE);
6347 		} else if ((va & L3C_OFFSET) == 0 && va + L3C_SIZE <= end &&
6348 		    m->psind >= 1 && pmap_ps_enabled(pmap) &&
6349 		    ((rv = pmap_enter_l3c_rx(pmap, va, m, &mpte, prot,
6350 		    &lock)) == KERN_SUCCESS || rv == KERN_NO_SPACE)) {
6351 			m = vm_radix_iter_jump(&pages, L3C_ENTRIES);
6352 		} else {
6353 			/*
6354 			 * In general, if a superpage mapping were possible,
6355 			 * it would have been created above.  That said, if
6356 			 * start and end are not superpage aligned, then
6357 			 * promotion might be possible at the ends of [start,
6358 			 * end).  However, in practice, those promotion
6359 			 * attempts are so unlikely to succeed that they are
6360 			 * not worth trying.
6361 			 */
6362 			mpte = pmap_enter_quick_locked(pmap, va, m, prot |
6363 			    VM_PROT_NO_PROMOTE, mpte, &lock);
6364 			m = vm_radix_iter_step(&pages);
6365 		}
6366 	}
6367 	if (lock != NULL)
6368 		rw_wunlock(lock);
6369 	PMAP_UNLOCK(pmap);
6370 }
6371 
6372 /*
6373  * this code makes some *MAJOR* assumptions:
6374  * 1. Current pmap & pmap exists.
6375  * 2. Not wired.
6376  * 3. Read access.
6377  * 4. No page table pages.
6378  * but is *MUCH* faster than pmap_enter...
6379  */
6380 
6381 void
6382 pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot)
6383 {
6384 	struct rwlock *lock;
6385 
6386 	lock = NULL;
6387 	PMAP_LOCK(pmap);
6388 	(void)pmap_enter_quick_locked(pmap, va, m, prot, NULL, &lock);
6389 	if (lock != NULL)
6390 		rw_wunlock(lock);
6391 	PMAP_UNLOCK(pmap);
6392 }
6393 
6394 static vm_page_t
6395 pmap_enter_quick_locked(pmap_t pmap, vm_offset_t va, vm_page_t m,
6396     vm_prot_t prot, vm_page_t mpte, struct rwlock **lockp)
6397 {
6398 	pt_entry_t *l1, *l2, *l3, l3_val;
6399 	vm_paddr_t pa;
6400 	int full_lvl, lvl;
6401 
6402 	KASSERT(!VA_IS_CLEANMAP(va) ||
6403 	    (m->oflags & VPO_UNMANAGED) != 0,
6404 	    ("pmap_enter_quick_locked: managed mapping within the clean submap"));
6405 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
6406 	PMAP_ASSERT_STAGE1(pmap);
6407 	KASSERT(ADDR_IS_CANONICAL(va),
6408 	    ("%s: Address not in canonical form: %lx", __func__, va));
6409 	l2 = NULL;
6410 
6411 	CTR2(KTR_PMAP, "pmap_enter_quick_locked: %p %lx", pmap, va);
6412 	/*
6413 	 * In the case that a page table page is not
6414 	 * resident, we are creating it here.
6415 	 */
6416 	if (ADDR_IS_USER(va)) {
6417 		vm_pindex_t l2pindex;
6418 
6419 		/*
6420 		 * Calculate pagetable page index
6421 		 */
6422 		l2pindex = pmap_l2_pindex(va);
6423 		if (mpte && (mpte->pindex == l2pindex)) {
6424 			mpte->ref_count++;
6425 		} else {
6426 			/*
6427 			 * If the page table page is mapped, we just increment
6428 			 * the hold count, and activate it.  Otherwise, we
6429 			 * attempt to allocate a page table page, passing NULL
6430 			 * instead of the PV list lock pointer because we don't
6431 			 * intend to sleep.  If this attempt fails, we don't
6432 			 * retry.  Instead, we give up.
6433 			 */
6434 			l1 = pmap_l1(pmap, va);
6435 			if (l1 != NULL && pmap_load(l1) != 0) {
6436 				if ((pmap_load(l1) & ATTR_DESCR_MASK) ==
6437 				    L1_BLOCK)
6438 					return (NULL);
6439 				l2 = pmap_l1_to_l2(l1, va);
6440 				if (pmap_load(l2) != 0) {
6441 					if ((pmap_load(l2) & ATTR_DESCR_MASK) ==
6442 					    L2_BLOCK)
6443 						return (NULL);
6444 					mpte = PTE_TO_VM_PAGE(pmap_load(l2));
6445 					mpte->ref_count++;
6446 				} else {
6447 					mpte = _pmap_alloc_l3(pmap, l2pindex,
6448 					    NULL);
6449 					if (mpte == NULL)
6450 						return (mpte);
6451 				}
6452 			} else {
6453 				mpte = _pmap_alloc_l3(pmap, l2pindex, NULL);
6454 				if (mpte == NULL)
6455 					return (mpte);
6456 			}
6457 		}
6458 		l3 = VM_PAGE_TO_DMAP(mpte);
6459 		l3 = &l3[pmap_l3_index(va)];
6460 	} else {
6461 		mpte = NULL;
6462 		l2 = pmap_pde(kernel_pmap, va, &lvl);
6463 		KASSERT(l2 != NULL,
6464 		    ("pmap_enter_quick_locked: Invalid page entry, va: 0x%lx",
6465 		     va));
6466 		KASSERT(lvl == 2,
6467 		    ("pmap_enter_quick_locked: Invalid level %d", lvl));
6468 		l3 = pmap_l2_to_l3(l2, va);
6469 	}
6470 
6471 	/*
6472 	 * Abort if a mapping already exists.
6473 	 */
6474 	if (pmap_load(l3) != 0) {
6475 		if (mpte != NULL)
6476 			mpte->ref_count--;
6477 		return (NULL);
6478 	}
6479 
6480 	/*
6481 	 * Enter on the PV list if part of our managed memory.
6482 	 */
6483 	if ((m->oflags & VPO_UNMANAGED) == 0 &&
6484 	    !pmap_try_insert_pv_entry(pmap, va, m, lockp)) {
6485 		if (mpte != NULL)
6486 			pmap_abort_ptp(pmap, va, mpte);
6487 		return (NULL);
6488 	}
6489 
6490 	/*
6491 	 * Increment counters
6492 	 */
6493 	pmap_resident_count_inc(pmap, 1);
6494 
6495 	pa = VM_PAGE_TO_PHYS(m);
6496 	l3_val = PHYS_TO_PTE(pa) | pmap_sh_attr |
6497 	    ATTR_S1_IDX(m->md.pv_memattr) | ATTR_S1_AP(ATTR_S1_AP_RO) | L3_PAGE;
6498 	l3_val |= pmap_pte_bti(pmap, va);
6499 	if ((prot & VM_PROT_EXECUTE) == 0 ||
6500 	    m->md.pv_memattr == VM_MEMATTR_DEVICE)
6501 		l3_val |= ATTR_S1_XN;
6502 	if (ADDR_IS_USER(va))
6503 		l3_val |= ATTR_S1_AP(ATTR_S1_AP_USER) | ATTR_S1_PXN;
6504 	else
6505 		l3_val |= ATTR_S1_UXN;
6506 	if (pmap != kernel_pmap)
6507 		l3_val |= ATTR_S1_nG;
6508 
6509 	/*
6510 	 * Now validate mapping with RO protection
6511 	 */
6512 	if ((m->oflags & VPO_UNMANAGED) == 0)
6513 		l3_val |= ATTR_SW_MANAGED;
6514 	else
6515 		l3_val |= ATTR_AF;
6516 
6517 	/* Sync icache before the mapping is stored to PTE */
6518 	if ((prot & VM_PROT_EXECUTE) && pmap != kernel_pmap &&
6519 	    m->md.pv_memattr == VM_MEMATTR_WRITE_BACK)
6520 		cpu_icache_sync_range(PHYS_TO_DMAP(pa), PAGE_SIZE);
6521 
6522 	pmap_store(l3, l3_val);
6523 	dsb(ishst);
6524 
6525 #if VM_NRESERVLEVEL > 0
6526 	/*
6527 	 * First, attempt L3C promotion, if the virtual and physical addresses
6528 	 * are aligned with each other and an underlying reservation has the
6529 	 * neighboring L3 pages allocated.  The first condition is simply an
6530 	 * optimization that recognizes some eventual promotion failures early
6531 	 * at a lower run-time cost.  Then, attempt L2 promotion, if both a
6532 	 * level 1 reservation and the PTP are fully populated.
6533 	 */
6534 	if ((prot & VM_PROT_NO_PROMOTE) == 0 &&
6535 	    (va & L3C_OFFSET) == (pa & L3C_OFFSET) &&
6536 	    (m->flags & PG_FICTITIOUS) == 0 &&
6537 	    (full_lvl = vm_reserv_level_iffullpop(m)) >= 0 &&
6538 	    pmap_promote_l3c(pmap, l3, va) &&
6539 	    full_lvl == 1 && (mpte == NULL || mpte->ref_count == NL3PG)) {
6540 		if (l2 == NULL)
6541 			l2 = pmap_l2(pmap, va);
6542 
6543 		/*
6544 		 * If promotion succeeds, then the next call to this function
6545 		 * should not be given the unmapped PTP as a hint.
6546 		 */
6547 		if (pmap_promote_l2(pmap, l2, va, mpte, lockp))
6548 			mpte = NULL;
6549 	}
6550 #endif
6551 
6552 	return (mpte);
6553 }
6554 
6555 /*
6556  * This code maps large physical mmap regions into the
6557  * processor address space.  Note that some shortcuts
6558  * are taken, but the code works.
6559  */
6560 void
6561 pmap_object_init_pt(pmap_t pmap, vm_offset_t addr, vm_object_t object,
6562     vm_pindex_t pindex, vm_size_t size)
6563 {
6564 
6565 	VM_OBJECT_ASSERT_WLOCKED(object);
6566 	KASSERT(object->type == OBJT_DEVICE || object->type == OBJT_SG,
6567 	    ("pmap_object_init_pt: non-device object"));
6568 }
6569 
6570 /*
6571  *	Clear the wired attribute from the mappings for the specified range of
6572  *	addresses in the given pmap.  Every valid mapping within that range
6573  *	must have the wired attribute set.  In contrast, invalid mappings
6574  *	cannot have the wired attribute set, so they are ignored.
6575  *
6576  *	The wired attribute of the page table entry is not a hardware feature,
6577  *	so there is no need to invalidate any TLB entries.
6578  */
6579 void
6580 pmap_unwire(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
6581 {
6582 	vm_offset_t va_next;
6583 	pd_entry_t *l0, *l1, *l2;
6584 	pt_entry_t *l3;
6585 	bool partial_l3c;
6586 
6587 	PMAP_LOCK(pmap);
6588 	for (; sva < eva; sva = va_next) {
6589 		l0 = pmap_l0(pmap, sva);
6590 		if (pmap_load(l0) == 0) {
6591 			va_next = (sva + L0_SIZE) & ~L0_OFFSET;
6592 			if (va_next < sva)
6593 				va_next = eva;
6594 			continue;
6595 		}
6596 
6597 		l1 = pmap_l0_to_l1(l0, sva);
6598 		va_next = (sva + L1_SIZE) & ~L1_OFFSET;
6599 		if (va_next < sva)
6600 			va_next = eva;
6601 		if (pmap_load(l1) == 0)
6602 			continue;
6603 
6604 		if ((pmap_load(l1) & ATTR_DESCR_MASK) == L1_BLOCK) {
6605 			PMAP_ASSERT_L1_BLOCKS_SUPPORTED;
6606 			KASSERT(va_next <= eva,
6607 			    ("partial update of non-transparent 1G page "
6608 			    "l1 %#lx sva %#lx eva %#lx va_next %#lx",
6609 			    pmap_load(l1), sva, eva, va_next));
6610 			MPASS(pmap != kernel_pmap);
6611 			MPASS((pmap_load(l1) & (ATTR_SW_MANAGED |
6612 			    ATTR_SW_WIRED)) == ATTR_SW_WIRED);
6613 			pmap_clear_bits(l1, ATTR_SW_WIRED);
6614 			pmap->pm_stats.wired_count -= L1_SIZE / PAGE_SIZE;
6615 			continue;
6616 		}
6617 
6618 		va_next = (sva + L2_SIZE) & ~L2_OFFSET;
6619 		if (va_next < sva)
6620 			va_next = eva;
6621 
6622 		l2 = pmap_l1_to_l2(l1, sva);
6623 		if (pmap_load(l2) == 0)
6624 			continue;
6625 
6626 		if ((pmap_load(l2) & ATTR_DESCR_MASK) == L2_BLOCK) {
6627 			if ((pmap_load(l2) & ATTR_SW_WIRED) == 0)
6628 				panic("pmap_unwire: l2 %#jx is missing "
6629 				    "ATTR_SW_WIRED", (uintmax_t)pmap_load(l2));
6630 
6631 			/*
6632 			 * Are we unwiring the entire large page?  If not,
6633 			 * demote the mapping and fall through.
6634 			 */
6635 			if (sva + L2_SIZE == va_next && eva >= va_next) {
6636 				pmap_clear_bits(l2, ATTR_SW_WIRED);
6637 				pmap->pm_stats.wired_count -= L2_SIZE /
6638 				    PAGE_SIZE;
6639 				continue;
6640 			} else if (pmap_demote_l2(pmap, l2, sva) == NULL)
6641 				panic("pmap_unwire: demotion failed");
6642 		}
6643 		KASSERT((pmap_load(l2) & ATTR_DESCR_MASK) == L2_TABLE,
6644 		    ("pmap_unwire: Invalid l2 entry after demotion"));
6645 
6646 		if (va_next > eva)
6647 			va_next = eva;
6648 		for (partial_l3c = true, l3 = pmap_l2_to_l3(l2, sva);
6649 		    sva != va_next; l3++, sva += L3_SIZE) {
6650 			if (pmap_load(l3) == 0)
6651 				continue;
6652 			if ((pmap_load(l3) & ATTR_CONTIGUOUS) != 0) {
6653 				/*
6654 				 * Avoid demotion for whole-page unwiring.
6655 				 */
6656 				if ((sva & L3C_OFFSET) == 0) {
6657 					/*
6658 					 * Handle the possibility that
6659 					 * "va_next" is zero because of
6660 					 * address wraparound.
6661 					 */
6662 					partial_l3c = sva + L3C_OFFSET >
6663 					    va_next - 1;
6664 				}
6665 				if (partial_l3c)
6666 					(void)pmap_demote_l3c(pmap, l3, sva);
6667 			}
6668 			if ((pmap_load(l3) & ATTR_SW_WIRED) == 0)
6669 				panic("pmap_unwire: l3 %#jx is missing "
6670 				    "ATTR_SW_WIRED", (uintmax_t)pmap_load(l3));
6671 
6672 			/*
6673 			 * ATTR_SW_WIRED must be cleared atomically.  Although
6674 			 * the pmap lock synchronizes access to ATTR_SW_WIRED,
6675 			 * the System MMU may write to the entry concurrently.
6676 			 */
6677 			pmap_clear_bits(l3, ATTR_SW_WIRED);
6678 			pmap->pm_stats.wired_count--;
6679 		}
6680 	}
6681 	PMAP_UNLOCK(pmap);
6682 }
6683 
6684 /*
6685  * This function requires that the caller has already added one to ml3's
6686  * ref_count in anticipation of creating a 4KB page mapping.
6687  */
6688 static bool
6689 pmap_copy_l3c(pmap_t pmap, pt_entry_t *l3p, vm_offset_t va, pt_entry_t l3e,
6690     vm_page_t ml3, struct rwlock **lockp)
6691 {
6692 	pt_entry_t *tl3p;
6693 
6694 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
6695 	KASSERT((va & L3C_OFFSET) == 0,
6696 	    ("pmap_copy_l3c: va is not aligned"));
6697 	KASSERT((l3e & ATTR_SW_MANAGED) != 0,
6698 	    ("pmap_copy_l3c: l3e is not managed"));
6699 
6700 	/*
6701 	 * Abort if a mapping already exists.
6702 	 */
6703 	for (tl3p = l3p; tl3p < &l3p[L3C_ENTRIES]; tl3p++)
6704 		if (pmap_load(tl3p) != 0) {
6705 			if (ml3 != NULL)
6706 				ml3->ref_count--;
6707 			return (false);
6708 		}
6709 
6710 	if (!pmap_pv_insert_l3c(pmap, va, PTE_TO_VM_PAGE(l3e), lockp)) {
6711 		if (ml3 != NULL)
6712 			pmap_abort_ptp(pmap, va, ml3);
6713 		return (false);
6714 	}
6715 	ml3->ref_count += L3C_ENTRIES - 1;
6716 
6717 	/*
6718 	 * Clear the wired and accessed bits.  However, leave the dirty bit
6719 	 * unchanged because read/write superpage mappings are required to be
6720 	 * dirty.
6721 	 */
6722 	l3e &= ~(ATTR_SW_WIRED | ATTR_AF);
6723 
6724 	for (tl3p = l3p; tl3p < &l3p[L3C_ENTRIES]; tl3p++) {
6725 		pmap_store(tl3p, l3e);
6726 		l3e += L3_SIZE;
6727 	}
6728 	pmap_resident_count_inc(pmap, L3C_ENTRIES);
6729 	counter_u64_add(pmap_l3c_mappings, 1);
6730 	CTR2(KTR_PMAP, "pmap_copy_l3c: success for va %#lx in pmap %p",
6731 	    va, pmap);
6732 	return (true);
6733 }
6734 
6735 /*
6736  *	Copy the range specified by src_addr/len
6737  *	from the source map to the range dst_addr/len
6738  *	in the destination map.
6739  *
6740  *	This routine is only advisory and need not do anything.
6741  *
6742  *	Because the executable mappings created by this routine are copied,
6743  *	it should not have to flush the instruction cache.
6744  */
6745 void
6746 pmap_copy(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr, vm_size_t len,
6747     vm_offset_t src_addr)
6748 {
6749 	struct rwlock *lock;
6750 	pd_entry_t *l0, *l1, *l2, srcptepaddr;
6751 	pt_entry_t *dst_pte, mask, nbits, ptetemp, *src_pte;
6752 	vm_offset_t addr, end_addr, va_next;
6753 	vm_page_t dst_m, dstmpte, srcmpte;
6754 
6755 	PMAP_ASSERT_STAGE1(dst_pmap);
6756 	PMAP_ASSERT_STAGE1(src_pmap);
6757 
6758 	if (dst_addr != src_addr)
6759 		return;
6760 	end_addr = src_addr + len;
6761 	lock = NULL;
6762 	if (dst_pmap < src_pmap) {
6763 		PMAP_LOCK(dst_pmap);
6764 		PMAP_LOCK(src_pmap);
6765 	} else {
6766 		PMAP_LOCK(src_pmap);
6767 		PMAP_LOCK(dst_pmap);
6768 	}
6769 	for (addr = src_addr; addr < end_addr; addr = va_next) {
6770 		l0 = pmap_l0(src_pmap, addr);
6771 		if (pmap_load(l0) == 0) {
6772 			va_next = (addr + L0_SIZE) & ~L0_OFFSET;
6773 			if (va_next < addr)
6774 				va_next = end_addr;
6775 			continue;
6776 		}
6777 
6778 		va_next = (addr + L1_SIZE) & ~L1_OFFSET;
6779 		if (va_next < addr)
6780 			va_next = end_addr;
6781 		l1 = pmap_l0_to_l1(l0, addr);
6782 		if (pmap_load(l1) == 0)
6783 			continue;
6784 		if ((pmap_load(l1) & ATTR_DESCR_MASK) == L1_BLOCK) {
6785 			PMAP_ASSERT_L1_BLOCKS_SUPPORTED;
6786 			KASSERT(va_next <= end_addr,
6787 			    ("partial update of non-transparent 1G page "
6788 			    "l1 %#lx addr %#lx end_addr %#lx va_next %#lx",
6789 			    pmap_load(l1), addr, end_addr, va_next));
6790 			srcptepaddr = pmap_load(l1);
6791 			l1 = pmap_l1(dst_pmap, addr);
6792 			if (l1 == NULL) {
6793 				if (_pmap_alloc_l3(dst_pmap,
6794 				    pmap_l0_pindex(addr), NULL) == NULL)
6795 					break;
6796 				l1 = pmap_l1(dst_pmap, addr);
6797 			} else {
6798 				l0 = pmap_l0(dst_pmap, addr);
6799 				dst_m = PTE_TO_VM_PAGE(pmap_load(l0));
6800 				dst_m->ref_count++;
6801 			}
6802 			KASSERT(pmap_load(l1) == 0,
6803 			    ("1G mapping present in dst pmap "
6804 			    "l1 %#lx addr %#lx end_addr %#lx va_next %#lx",
6805 			    pmap_load(l1), addr, end_addr, va_next));
6806 			pmap_store(l1, srcptepaddr & ~ATTR_SW_WIRED);
6807 			pmap_resident_count_inc(dst_pmap, L1_SIZE / PAGE_SIZE);
6808 			continue;
6809 		}
6810 
6811 		va_next = (addr + L2_SIZE) & ~L2_OFFSET;
6812 		if (va_next < addr)
6813 			va_next = end_addr;
6814 		l2 = pmap_l1_to_l2(l1, addr);
6815 		srcptepaddr = pmap_load(l2);
6816 		if (srcptepaddr == 0)
6817 			continue;
6818 		if ((srcptepaddr & ATTR_DESCR_MASK) == L2_BLOCK) {
6819 			/*
6820 			 * We can only virtual copy whole superpages.
6821 			 */
6822 			if ((addr & L2_OFFSET) != 0 ||
6823 			    addr + L2_SIZE > end_addr)
6824 				continue;
6825 			l2 = pmap_alloc_l2(dst_pmap, addr, &dst_m, NULL);
6826 			if (l2 == NULL)
6827 				break;
6828 			if (pmap_load(l2) == 0 &&
6829 			    ((srcptepaddr & ATTR_SW_MANAGED) == 0 ||
6830 			    pmap_pv_insert_l2(dst_pmap, addr, srcptepaddr,
6831 			    PMAP_ENTER_NORECLAIM, &lock))) {
6832 				/*
6833 				 * We leave the dirty bit unchanged because
6834 				 * managed read/write superpage mappings are
6835 				 * required to be dirty.  However, managed
6836 				 * superpage mappings are not required to
6837 				 * have their accessed bit set, so we clear
6838 				 * it because we don't know if this mapping
6839 				 * will be used.
6840 				 */
6841 				srcptepaddr &= ~ATTR_SW_WIRED;
6842 				if ((srcptepaddr & ATTR_SW_MANAGED) != 0)
6843 					srcptepaddr &= ~ATTR_AF;
6844 				pmap_store(l2, srcptepaddr);
6845 				pmap_resident_count_inc(dst_pmap, L2_SIZE /
6846 				    PAGE_SIZE);
6847 				counter_u64_add(pmap_l2_mappings, 1);
6848 			} else
6849 				pmap_abort_ptp(dst_pmap, addr, dst_m);
6850 			continue;
6851 		}
6852 		KASSERT((srcptepaddr & ATTR_DESCR_MASK) == L2_TABLE,
6853 		    ("pmap_copy: invalid L2 entry"));
6854 		srcmpte = PTE_TO_VM_PAGE(srcptepaddr);
6855 		KASSERT(srcmpte->ref_count > 0,
6856 		    ("pmap_copy: source page table page is unused"));
6857 		if (va_next > end_addr)
6858 			va_next = end_addr;
6859 		src_pte = PHYS_TO_DMAP(PTE_TO_PHYS(srcptepaddr));
6860 		src_pte = &src_pte[pmap_l3_index(addr)];
6861 		dstmpte = NULL;
6862 		for (; addr < va_next; addr += PAGE_SIZE, src_pte++) {
6863 			ptetemp = pmap_load(src_pte);
6864 
6865 			/*
6866 			 * We only virtual copy managed pages.
6867 			 */
6868 			if ((ptetemp & ATTR_SW_MANAGED) == 0)
6869 				continue;
6870 
6871 			if (dstmpte != NULL) {
6872 				KASSERT(dstmpte->pindex == pmap_l2_pindex(addr),
6873 				    ("dstmpte pindex/addr mismatch"));
6874 				dstmpte->ref_count++;
6875 			} else if ((dstmpte = pmap_alloc_l3(dst_pmap, addr,
6876 			    NULL)) == NULL)
6877 				goto out;
6878 			dst_pte = VM_PAGE_TO_DMAP(dstmpte);
6879 			dst_pte = &dst_pte[pmap_l3_index(addr)];
6880 			if ((ptetemp & ATTR_CONTIGUOUS) != 0 && (addr &
6881 			    L3C_OFFSET) == 0 && addr + L3C_OFFSET <=
6882 			    va_next - 1) {
6883 				if (!pmap_copy_l3c(dst_pmap, dst_pte, addr,
6884 				    ptetemp, dstmpte, &lock))
6885 					goto out;
6886 				addr += L3C_SIZE - PAGE_SIZE;
6887 				src_pte += L3C_ENTRIES - 1;
6888 			} else if (pmap_load(dst_pte) == 0 &&
6889 			    pmap_try_insert_pv_entry(dst_pmap, addr,
6890 			    PTE_TO_VM_PAGE(ptetemp), &lock)) {
6891 				/*
6892 				 * Clear the wired, contiguous, modified, and
6893 				 * accessed bits from the destination PTE.
6894 				 * The contiguous bit is cleared because we
6895 				 * are not copying the entire L3C superpage.
6896 				 */
6897 				mask = ATTR_SW_WIRED | ATTR_CONTIGUOUS |
6898 				    ATTR_AF;
6899 				nbits = 0;
6900 				if ((ptetemp & ATTR_SW_DBM) != 0)
6901 					nbits |= ATTR_S1_AP_RW_BIT;
6902 				pmap_store(dst_pte, (ptetemp & ~mask) | nbits);
6903 				pmap_resident_count_inc(dst_pmap, 1);
6904 			} else {
6905 				pmap_abort_ptp(dst_pmap, addr, dstmpte);
6906 				goto out;
6907 			}
6908 			/* Have we copied all of the valid mappings? */
6909 			if (dstmpte->ref_count >= srcmpte->ref_count)
6910 				break;
6911 		}
6912 	}
6913 out:
6914 	/*
6915 	 * XXX This barrier may not be needed because the destination pmap is
6916 	 * not active.
6917 	 */
6918 	dsb(ishst);
6919 
6920 	if (lock != NULL)
6921 		rw_wunlock(lock);
6922 	PMAP_UNLOCK(src_pmap);
6923 	PMAP_UNLOCK(dst_pmap);
6924 }
6925 
6926 int
6927 pmap_vmspace_copy(pmap_t dst_pmap, pmap_t src_pmap)
6928 {
6929 	int error;
6930 
6931 	if (dst_pmap->pm_stage != src_pmap->pm_stage)
6932 		return (EINVAL);
6933 
6934 	if (dst_pmap->pm_stage != PM_STAGE1 || src_pmap->pm_bti == NULL)
6935 		return (0);
6936 
6937 	for (;;) {
6938 		if (dst_pmap < src_pmap) {
6939 			PMAP_LOCK(dst_pmap);
6940 			PMAP_LOCK(src_pmap);
6941 		} else {
6942 			PMAP_LOCK(src_pmap);
6943 			PMAP_LOCK(dst_pmap);
6944 		}
6945 		error = pmap_bti_copy(dst_pmap, src_pmap);
6946 		/* Clean up partial copy on failure due to no memory. */
6947 		if (error == ENOMEM)
6948 			pmap_bti_deassign_all(dst_pmap);
6949 		PMAP_UNLOCK(src_pmap);
6950 		PMAP_UNLOCK(dst_pmap);
6951 		if (error != ENOMEM)
6952 			break;
6953 		vm_wait(NULL);
6954 	}
6955 	return (error);
6956 }
6957 
6958 /*
6959  *	pmap_zero_page zeros the specified hardware page by mapping
6960  *	the page into KVM and using bzero to clear its contents.
6961  */
6962 void
6963 pmap_zero_page(vm_page_t m)
6964 {
6965 	void *va = VM_PAGE_TO_DMAP(m);
6966 
6967 	pagezero(va);
6968 	m->md.pv_flags &= ~PV_MTE_TAGGED;
6969 }
6970 
6971 /*
6972  *	pmap_zero_page_area zeros the specified hardware page by mapping
6973  *	the page into KVM and using bzero to clear its contents.
6974  *
6975  *	off and size may not cover an area beyond a single hardware page.
6976  */
6977 void
6978 pmap_zero_page_area(vm_page_t m, int off, int size)
6979 {
6980 	void *va = VM_PAGE_TO_DMAP(m);
6981 
6982 	if (off == 0 && size == PAGE_SIZE)
6983 		pagezero(va);
6984 	else
6985 		bzero((char *)va + off, size);
6986 }
6987 
6988 /*
6989  *	pmap_copy_page copies the specified (machine independent)
6990  *	page by mapping the page into virtual memory and using
6991  *	memcpy to copy the page, one machine dependent page at a
6992  *	time.
6993  */
6994 void
6995 pmap_copy_page(vm_page_t msrc, vm_page_t mdst)
6996 {
6997 	void *src = VM_PAGE_TO_DMAP(msrc);
6998 	void *dst = VM_PAGE_TO_DMAP(mdst);
6999 
7000 	/*
7001 	 * On a page copy, check whether the src page is tagged. If it is,
7002 	 * we must copy the tags before copying the contents of the page.
7003 	 */
7004 	if ((msrc->md.pv_flags & PV_MTE_TAGGED) != 0)
7005 		mte_copy_tags(msrc, mdst, src, dst);
7006 	else
7007 		mdst->md.pv_flags &= ~PV_MTE_TAGGED;
7008 
7009 	pagecopy(src, dst);
7010 }
7011 
7012 int unmapped_buf_allowed = 1;
7013 
7014 void
7015 pmap_copy_pages(vm_page_t ma[], vm_offset_t a_offset, vm_page_t mb[],
7016     vm_offset_t b_offset, int xfersize)
7017 {
7018 	void *a_cp, *b_cp;
7019 	vm_page_t m_a, m_b;
7020 	vm_paddr_t p_a, p_b;
7021 	vm_offset_t a_pg_offset, b_pg_offset;
7022 	int cnt;
7023 
7024 	while (xfersize > 0) {
7025 		KASSERT(ADDR_IS_CANONICAL(a_offset),
7026 		    ("%s: Address not in canonical form: %lx", __func__, a_offset));
7027 
7028 		a_pg_offset = a_offset & PAGE_MASK;
7029 		m_a = ma[a_offset >> PAGE_SHIFT];
7030 		p_a = m_a->phys_addr;
7031 		b_pg_offset = b_offset & PAGE_MASK;
7032 		m_b = mb[b_offset >> PAGE_SHIFT];
7033 		p_b = m_b->phys_addr;
7034 		cnt = min(xfersize, PAGE_SIZE - a_pg_offset);
7035 		cnt = min(cnt, PAGE_SIZE - b_pg_offset);
7036 		if (__predict_false(!PHYS_IN_DMAP(p_a))) {
7037 			panic("!DMAP a %lx", p_a);
7038 		} else {
7039 			a_cp = (char *)PHYS_TO_DMAP(p_a) + a_pg_offset;
7040 		}
7041 		if (__predict_false(!PHYS_IN_DMAP(p_b))) {
7042 			panic("!DMAP b %lx", p_b);
7043 		} else {
7044 			b_cp = (char *)PHYS_TO_DMAP(p_b) + b_pg_offset;
7045 		}
7046 		memcpy(b_cp, a_cp, cnt);
7047 		a_offset += cnt;
7048 		b_offset += cnt;
7049 		xfersize -= cnt;
7050 	}
7051 }
7052 
7053 void *
7054 pmap_quick_enter_page(vm_page_t m)
7055 {
7056 
7057 	return (VM_PAGE_TO_DMAP(m));
7058 }
7059 
7060 void
7061 pmap_quick_remove_page(void *addr)
7062 {
7063 }
7064 
7065 /*
7066  * Returns true if the pmap's pv is one of the first
7067  * 16 pvs linked to from this page.  This count may
7068  * be changed upwards or downwards in the future; it
7069  * is only necessary that true be returned for a small
7070  * subset of pmaps for proper page aging.
7071  */
7072 bool
7073 pmap_page_exists_quick(pmap_t pmap, vm_page_t m)
7074 {
7075 	struct md_page *pvh;
7076 	struct rwlock *lock;
7077 	pv_entry_t pv;
7078 	int loops = 0;
7079 	bool rv;
7080 
7081 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
7082 	    ("pmap_page_exists_quick: page %p is not managed", m));
7083 	rv = false;
7084 	lock = VM_PAGE_TO_PV_LIST_LOCK(m);
7085 	rw_rlock(lock);
7086 	TAILQ_FOREACH(pv, &m->md.pv_list, pv_next) {
7087 		if (PV_PMAP(pv) == pmap) {
7088 			rv = true;
7089 			break;
7090 		}
7091 		loops++;
7092 		if (loops >= 16)
7093 			break;
7094 	}
7095 	if (!rv && loops < 16 && (m->flags & PG_FICTITIOUS) == 0) {
7096 		pvh = page_to_pvh(m);
7097 		TAILQ_FOREACH(pv, &pvh->pv_list, pv_next) {
7098 			if (PV_PMAP(pv) == pmap) {
7099 				rv = true;
7100 				break;
7101 			}
7102 			loops++;
7103 			if (loops >= 16)
7104 				break;
7105 		}
7106 	}
7107 	rw_runlock(lock);
7108 	return (rv);
7109 }
7110 
7111 /*
7112  *	pmap_page_wired_mappings:
7113  *
7114  *	Return the number of managed mappings to the given physical page
7115  *	that are wired.
7116  */
7117 int
7118 pmap_page_wired_mappings(vm_page_t m)
7119 {
7120 	struct rwlock *lock;
7121 	struct md_page *pvh;
7122 	pmap_t pmap;
7123 	pt_entry_t *pte;
7124 	pv_entry_t pv;
7125 	int count, md_gen, pvh_gen;
7126 
7127 	if ((m->oflags & VPO_UNMANAGED) != 0)
7128 		return (0);
7129 	lock = VM_PAGE_TO_PV_LIST_LOCK(m);
7130 	rw_rlock(lock);
7131 restart:
7132 	count = 0;
7133 	TAILQ_FOREACH(pv, &m->md.pv_list, pv_next) {
7134 		pmap = PV_PMAP(pv);
7135 		if (!PMAP_TRYLOCK(pmap)) {
7136 			md_gen = m->md.pv_gen;
7137 			rw_runlock(lock);
7138 			PMAP_LOCK(pmap);
7139 			rw_rlock(lock);
7140 			if (md_gen != m->md.pv_gen) {
7141 				PMAP_UNLOCK(pmap);
7142 				goto restart;
7143 			}
7144 		}
7145 		pte = pmap_pte_exists(pmap, pv->pv_va, 3, __func__);
7146 		if ((pmap_load(pte) & ATTR_SW_WIRED) != 0)
7147 			count++;
7148 		PMAP_UNLOCK(pmap);
7149 	}
7150 	if ((m->flags & PG_FICTITIOUS) == 0) {
7151 		pvh = page_to_pvh(m);
7152 		TAILQ_FOREACH(pv, &pvh->pv_list, pv_next) {
7153 			pmap = PV_PMAP(pv);
7154 			if (!PMAP_TRYLOCK(pmap)) {
7155 				md_gen = m->md.pv_gen;
7156 				pvh_gen = pvh->pv_gen;
7157 				rw_runlock(lock);
7158 				PMAP_LOCK(pmap);
7159 				rw_rlock(lock);
7160 				if (md_gen != m->md.pv_gen ||
7161 				    pvh_gen != pvh->pv_gen) {
7162 					PMAP_UNLOCK(pmap);
7163 					goto restart;
7164 				}
7165 			}
7166 			pte = pmap_pte_exists(pmap, pv->pv_va, 2, __func__);
7167 			if ((pmap_load(pte) & ATTR_SW_WIRED) != 0)
7168 				count++;
7169 			PMAP_UNLOCK(pmap);
7170 		}
7171 	}
7172 	rw_runlock(lock);
7173 	return (count);
7174 }
7175 
7176 /*
7177  * Returns true if the given page is mapped individually or as part of
7178  * a 2mpage.  Otherwise, returns false.
7179  */
7180 bool
7181 pmap_page_is_mapped(vm_page_t m)
7182 {
7183 	struct rwlock *lock;
7184 	bool rv;
7185 
7186 	if ((m->oflags & VPO_UNMANAGED) != 0)
7187 		return (false);
7188 	lock = VM_PAGE_TO_PV_LIST_LOCK(m);
7189 	rw_rlock(lock);
7190 	rv = !TAILQ_EMPTY(&m->md.pv_list) ||
7191 	    ((m->flags & PG_FICTITIOUS) == 0 &&
7192 	    !TAILQ_EMPTY(&page_to_pvh(m)->pv_list));
7193 	rw_runlock(lock);
7194 	return (rv);
7195 }
7196 
7197 /*
7198  * Destroy all managed, non-wired mappings in the given user-space
7199  * pmap.  This pmap cannot be active on any processor besides the
7200  * caller.
7201  *
7202  * This function cannot be applied to the kernel pmap.  Moreover, it
7203  * is not intended for general use.  It is only to be used during
7204  * process termination.  Consequently, it can be implemented in ways
7205  * that make it faster than pmap_remove().  First, it can more quickly
7206  * destroy mappings by iterating over the pmap's collection of PV
7207  * entries, rather than searching the page table.  Second, it doesn't
7208  * have to test and clear the page table entries atomically, because
7209  * no processor is currently accessing the user address space.  In
7210  * particular, a page table entry's dirty bit won't change state once
7211  * this function starts.
7212  */
7213 void
7214 pmap_remove_pages(pmap_t pmap)
7215 {
7216 	pd_entry_t *pde;
7217 	pt_entry_t *pte, tpte;
7218 	struct spglist free;
7219 	struct pv_chunklist free_chunks[PMAP_MEMDOM];
7220 	vm_page_t m, ml3, mt;
7221 	pv_entry_t pv;
7222 	struct md_page *pvh;
7223 	struct pv_chunk *pc, *npc;
7224 	struct rwlock *lock;
7225 	int64_t bit;
7226 	uint64_t inuse, bitmask;
7227 	int allfree, field, i, idx, lvl;
7228 	int freed __pvused;
7229 	vm_paddr_t pa;
7230 
7231 	lock = NULL;
7232 
7233 	for (i = 0; i < PMAP_MEMDOM; i++)
7234 		TAILQ_INIT(&free_chunks[i]);
7235 	SLIST_INIT(&free);
7236 	PMAP_LOCK(pmap);
7237 	TAILQ_FOREACH_SAFE(pc, &pmap->pm_pvchunk, pc_list, npc) {
7238 		allfree = 1;
7239 		freed = 0;
7240 		for (field = 0; field < _NPCM; field++) {
7241 			inuse = ~pc->pc_map[field] & pc_freemask[field];
7242 			while (inuse != 0) {
7243 				bit = ffsl(inuse) - 1;
7244 				bitmask = 1UL << bit;
7245 				idx = field * 64 + bit;
7246 				pv = &pc->pc_pventry[idx];
7247 				inuse &= ~bitmask;
7248 
7249 				pde = pmap_pde(pmap, pv->pv_va, &lvl);
7250 				KASSERT(pde != NULL,
7251 				    ("Attempting to remove an unmapped page"));
7252 
7253 				switch(lvl) {
7254 				case 1:
7255 					pte = pmap_l1_to_l2(pde, pv->pv_va);
7256 					tpte = pmap_load(pte);
7257 					KASSERT((tpte & ATTR_DESCR_MASK) ==
7258 					    L2_BLOCK,
7259 					    ("Attempting to remove an invalid "
7260 					    "block: %lx", tpte));
7261 					break;
7262 				case 2:
7263 					pte = pmap_l2_to_l3(pde, pv->pv_va);
7264 					tpte = pmap_load(pte);
7265 					KASSERT((tpte & ATTR_DESCR_MASK) ==
7266 					    L3_PAGE,
7267 					    ("Attempting to remove an invalid "
7268 					     "page: %lx", tpte));
7269 					break;
7270 				default:
7271 					panic(
7272 					    "Invalid page directory level: %d",
7273 					    lvl);
7274 				}
7275 
7276 				/*
7277 				 * We cannot remove wired mappings at this time.
7278 				 *
7279 				 * For L3C superpages, all of the constituent PTEs
7280 				 * should have the wired bit set, so we don't
7281 				 * check for ATTR_CONTIGUOUS here.
7282 				 */
7283 				if (tpte & ATTR_SW_WIRED) {
7284 					allfree = 0;
7285 					continue;
7286 				}
7287 
7288 				/* Mark free */
7289 				pc->pc_map[field] |= bitmask;
7290 
7291 				/*
7292 				 * Because this pmap is not active on other
7293 				 * processors, the dirty bit cannot have
7294 				 * changed state since we last loaded pte.
7295 				 */
7296 				pmap_clear(pte);
7297 
7298 				pa = PTE_TO_PHYS(tpte);
7299 
7300 				m = PHYS_TO_VM_PAGE(pa);
7301 				KASSERT(m->phys_addr == pa,
7302 				    ("vm_page_t %p phys_addr mismatch %016jx %016jx",
7303 				    m, (uintmax_t)m->phys_addr,
7304 				    (uintmax_t)tpte));
7305 
7306 				KASSERT((m->flags & PG_FICTITIOUS) != 0 ||
7307 				    m < &vm_page_array[vm_page_array_size],
7308 				    ("pmap_remove_pages: bad pte %#jx",
7309 				    (uintmax_t)tpte));
7310 
7311 				/*
7312 				 * Update the vm_page_t clean/reference bits.
7313 				 *
7314 				 * We don't check for ATTR_CONTIGUOUS here
7315 				 * because writeable L3C superpages are expected
7316 				 * to be dirty, i.e., every constituent PTE
7317 				 * should be dirty.
7318 				 */
7319 				if (pmap_pte_dirty(pmap, tpte)) {
7320 					switch (lvl) {
7321 					case 1:
7322 						for (mt = m; mt < &m[L2_SIZE / PAGE_SIZE]; mt++)
7323 							vm_page_dirty(mt);
7324 						break;
7325 					case 2:
7326 						vm_page_dirty(m);
7327 						break;
7328 					}
7329 				}
7330 
7331 				CHANGE_PV_LIST_LOCK_TO_VM_PAGE(&lock, m);
7332 
7333 				switch (lvl) {
7334 				case 1:
7335 					pmap_resident_count_dec(pmap,
7336 					    L2_SIZE / PAGE_SIZE);
7337 					pvh = page_to_pvh(m);
7338 					TAILQ_REMOVE(&pvh->pv_list, pv,pv_next);
7339 					pvh->pv_gen++;
7340 					if (TAILQ_EMPTY(&pvh->pv_list)) {
7341 						for (mt = m; mt < &m[L2_SIZE / PAGE_SIZE]; mt++)
7342 							if ((mt->a.flags & PGA_WRITEABLE) != 0 &&
7343 							    TAILQ_EMPTY(&mt->md.pv_list))
7344 								vm_page_aflag_clear(mt, PGA_WRITEABLE);
7345 					}
7346 					ml3 = pmap_remove_pt_page(pmap,
7347 					    pv->pv_va);
7348 					if (ml3 != NULL) {
7349 						KASSERT(vm_page_any_valid(ml3),
7350 						    ("pmap_remove_pages: l3 page not promoted"));
7351 						pmap_resident_count_dec(pmap,1);
7352 						KASSERT(ml3->ref_count == NL3PG,
7353 						    ("pmap_remove_pages: l3 page ref count error"));
7354 						ml3->ref_count = 0;
7355 						pmap_add_delayed_free_list(ml3,
7356 						    &free, false);
7357 					}
7358 					break;
7359 				case 2:
7360 					pmap_resident_count_dec(pmap, 1);
7361 					TAILQ_REMOVE(&m->md.pv_list, pv,
7362 					    pv_next);
7363 					m->md.pv_gen++;
7364 					if ((m->a.flags & PGA_WRITEABLE) != 0 &&
7365 					    TAILQ_EMPTY(&m->md.pv_list) &&
7366 					    (m->flags & PG_FICTITIOUS) == 0) {
7367 						pvh = page_to_pvh(m);
7368 						if (TAILQ_EMPTY(&pvh->pv_list))
7369 							vm_page_aflag_clear(m,
7370 							    PGA_WRITEABLE);
7371 					}
7372 					break;
7373 				}
7374 				pmap_unuse_pt(pmap, pv->pv_va, pmap_load(pde),
7375 				    &free);
7376 				freed++;
7377 			}
7378 		}
7379 		PV_STAT(atomic_add_long(&pv_entry_frees, freed));
7380 		PV_STAT(atomic_add_int(&pv_entry_spare, freed));
7381 		PV_STAT(atomic_subtract_long(&pv_entry_count, freed));
7382 		if (allfree) {
7383 			TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
7384 			TAILQ_INSERT_TAIL(&free_chunks[pc_to_domain(pc)], pc,
7385 			    pc_list);
7386 		}
7387 	}
7388 	if (lock != NULL)
7389 		rw_wunlock(lock);
7390 	pmap_invalidate_all(pmap);
7391 	pmap_bti_deassign_all(pmap);
7392 	free_pv_chunk_batch(free_chunks);
7393 	PMAP_UNLOCK(pmap);
7394 	vm_page_free_pages_toq(&free, true);
7395 }
7396 
7397 /*
7398  * This is used to check if a page has been accessed or modified.
7399  */
7400 static bool
7401 pmap_page_test_mappings(vm_page_t m, bool accessed, bool modified)
7402 {
7403 	struct rwlock *lock;
7404 	pv_entry_t pv;
7405 	struct md_page *pvh;
7406 	pt_entry_t l3e, mask, *pte, value;
7407 	pmap_t pmap;
7408 	int md_gen, pvh_gen;
7409 	bool rv;
7410 
7411 	rv = false;
7412 	lock = VM_PAGE_TO_PV_LIST_LOCK(m);
7413 	rw_rlock(lock);
7414 restart:
7415 	TAILQ_FOREACH(pv, &m->md.pv_list, pv_next) {
7416 		pmap = PV_PMAP(pv);
7417 		PMAP_ASSERT_STAGE1(pmap);
7418 		if (!PMAP_TRYLOCK(pmap)) {
7419 			md_gen = m->md.pv_gen;
7420 			rw_runlock(lock);
7421 			PMAP_LOCK(pmap);
7422 			rw_rlock(lock);
7423 			if (md_gen != m->md.pv_gen) {
7424 				PMAP_UNLOCK(pmap);
7425 				goto restart;
7426 			}
7427 		}
7428 		pte = pmap_pte_exists(pmap, pv->pv_va, 3, __func__);
7429 		mask = 0;
7430 		value = 0;
7431 		if (modified) {
7432 			mask |= ATTR_S1_AP_RW_BIT;
7433 			value |= ATTR_S1_AP(ATTR_S1_AP_RW);
7434 		}
7435 		if (accessed) {
7436 			mask |= ATTR_AF | ATTR_DESCR_MASK;
7437 			value |= ATTR_AF | L3_PAGE;
7438 		}
7439 		l3e = pmap_load(pte);
7440 		if ((l3e & ATTR_CONTIGUOUS) != 0)
7441 			l3e = pmap_load_l3c(pte);
7442 		PMAP_UNLOCK(pmap);
7443 		rv = (l3e & mask) == value;
7444 		if (rv)
7445 			goto out;
7446 	}
7447 	if ((m->flags & PG_FICTITIOUS) == 0) {
7448 		pvh = page_to_pvh(m);
7449 		TAILQ_FOREACH(pv, &pvh->pv_list, pv_next) {
7450 			pmap = PV_PMAP(pv);
7451 			PMAP_ASSERT_STAGE1(pmap);
7452 			if (!PMAP_TRYLOCK(pmap)) {
7453 				md_gen = m->md.pv_gen;
7454 				pvh_gen = pvh->pv_gen;
7455 				rw_runlock(lock);
7456 				PMAP_LOCK(pmap);
7457 				rw_rlock(lock);
7458 				if (md_gen != m->md.pv_gen ||
7459 				    pvh_gen != pvh->pv_gen) {
7460 					PMAP_UNLOCK(pmap);
7461 					goto restart;
7462 				}
7463 			}
7464 			pte = pmap_pte_exists(pmap, pv->pv_va, 2, __func__);
7465 			mask = 0;
7466 			value = 0;
7467 			if (modified) {
7468 				mask |= ATTR_S1_AP_RW_BIT;
7469 				value |= ATTR_S1_AP(ATTR_S1_AP_RW);
7470 			}
7471 			if (accessed) {
7472 				mask |= ATTR_AF | ATTR_DESCR_MASK;
7473 				value |= ATTR_AF | L2_BLOCK;
7474 			}
7475 			rv = (pmap_load(pte) & mask) == value;
7476 			PMAP_UNLOCK(pmap);
7477 			if (rv)
7478 				goto out;
7479 		}
7480 	}
7481 out:
7482 	rw_runlock(lock);
7483 	return (rv);
7484 }
7485 
7486 /*
7487  *	pmap_is_modified:
7488  *
7489  *	Return whether or not the specified physical page was modified
7490  *	in any physical maps.
7491  */
7492 bool
7493 pmap_is_modified(vm_page_t m)
7494 {
7495 
7496 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
7497 	    ("pmap_is_modified: page %p is not managed", m));
7498 
7499 	/*
7500 	 * If the page is not busied then this check is racy.
7501 	 */
7502 	if (!pmap_page_is_write_mapped(m))
7503 		return (false);
7504 	return (pmap_page_test_mappings(m, false, true));
7505 }
7506 
7507 /*
7508  *	pmap_is_prefaultable:
7509  *
7510  *	Return whether or not the specified virtual address is eligible
7511  *	for prefault.
7512  */
7513 bool
7514 pmap_is_prefaultable(pmap_t pmap, vm_offset_t addr)
7515 {
7516 	pd_entry_t *pde;
7517 	pt_entry_t *pte;
7518 	bool rv;
7519 	int lvl;
7520 
7521 	/*
7522 	 * Return true if and only if the L3 entry for the specified virtual
7523 	 * address is allocated but invalid.
7524 	 */
7525 	rv = false;
7526 	PMAP_LOCK(pmap);
7527 	pde = pmap_pde(pmap, addr, &lvl);
7528 	if (pde != NULL && lvl == 2) {
7529 		pte = pmap_l2_to_l3(pde, addr);
7530 		rv = pmap_load(pte) == 0;
7531 	}
7532 	PMAP_UNLOCK(pmap);
7533 	return (rv);
7534 }
7535 
7536 /*
7537  *	pmap_is_referenced:
7538  *
7539  *	Return whether or not the specified physical page was referenced
7540  *	in any physical maps.
7541  */
7542 bool
7543 pmap_is_referenced(vm_page_t m)
7544 {
7545 
7546 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
7547 	    ("pmap_is_referenced: page %p is not managed", m));
7548 	return (pmap_page_test_mappings(m, true, false));
7549 }
7550 
7551 /*
7552  * Clear the write and modified bits in each of the given page's mappings.
7553  */
7554 void
7555 pmap_remove_write(vm_page_t m)
7556 {
7557 	struct md_page *pvh;
7558 	pmap_t pmap;
7559 	struct rwlock *lock;
7560 	pv_entry_t next_pv, pv;
7561 	pt_entry_t oldpte, *pte, set, clear, mask, val;
7562 	vm_offset_t va;
7563 	int md_gen, pvh_gen;
7564 
7565 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
7566 	    ("pmap_remove_write: page %p is not managed", m));
7567 	vm_page_assert_busied(m);
7568 
7569 	if (!pmap_page_is_write_mapped(m))
7570 		return;
7571 	lock = VM_PAGE_TO_PV_LIST_LOCK(m);
7572 	pvh = (m->flags & PG_FICTITIOUS) != 0 ? &pv_dummy : page_to_pvh(m);
7573 	rw_wlock(lock);
7574 retry:
7575 	TAILQ_FOREACH_SAFE(pv, &pvh->pv_list, pv_next, next_pv) {
7576 		pmap = PV_PMAP(pv);
7577 		PMAP_ASSERT_STAGE1(pmap);
7578 		if (!PMAP_TRYLOCK(pmap)) {
7579 			pvh_gen = pvh->pv_gen;
7580 			rw_wunlock(lock);
7581 			PMAP_LOCK(pmap);
7582 			rw_wlock(lock);
7583 			if (pvh_gen != pvh->pv_gen) {
7584 				PMAP_UNLOCK(pmap);
7585 				goto retry;
7586 			}
7587 		}
7588 		va = pv->pv_va;
7589 		pte = pmap_pte_exists(pmap, va, 2, __func__);
7590 		if ((pmap_load(pte) & ATTR_SW_DBM) != 0)
7591 			(void)pmap_demote_l2_locked(pmap, pte, va, &lock);
7592 		KASSERT(lock == VM_PAGE_TO_PV_LIST_LOCK(m),
7593 		    ("inconsistent pv lock %p %p for page %p",
7594 		    lock, VM_PAGE_TO_PV_LIST_LOCK(m), m));
7595 		PMAP_UNLOCK(pmap);
7596 	}
7597 	TAILQ_FOREACH(pv, &m->md.pv_list, pv_next) {
7598 		pmap = PV_PMAP(pv);
7599 		if (!PMAP_TRYLOCK(pmap)) {
7600 			pvh_gen = pvh->pv_gen;
7601 			md_gen = m->md.pv_gen;
7602 			rw_wunlock(lock);
7603 			PMAP_LOCK(pmap);
7604 			rw_wlock(lock);
7605 			if (pvh_gen != pvh->pv_gen ||
7606 			    md_gen != m->md.pv_gen) {
7607 				PMAP_UNLOCK(pmap);
7608 				goto retry;
7609 			}
7610 		}
7611 		pte = pmap_pte_exists(pmap, pv->pv_va, 3, __func__);
7612 		oldpte = pmap_load(pte);
7613 		if ((oldpte & ATTR_SW_DBM) != 0) {
7614 			if ((oldpte & ATTR_CONTIGUOUS) != 0) {
7615 				(void)pmap_demote_l3c(pmap, pte, pv->pv_va);
7616 
7617 				/*
7618 				 * The L3 entry's accessed bit may have
7619 				 * changed.
7620 				 */
7621 				oldpte = pmap_load(pte);
7622 			}
7623 			if (pmap->pm_stage == PM_STAGE1) {
7624 				set = ATTR_S1_AP_RW_BIT;
7625 				clear = 0;
7626 				mask = ATTR_S1_AP_RW_BIT;
7627 				val = ATTR_S1_AP(ATTR_S1_AP_RW);
7628 			} else {
7629 				set = 0;
7630 				clear = ATTR_S2_S2AP(ATTR_S2_S2AP_WRITE);
7631 				mask = ATTR_S2_S2AP(ATTR_S2_S2AP_WRITE);
7632 				val = ATTR_S2_S2AP(ATTR_S2_S2AP_WRITE);
7633 			}
7634 			clear |= ATTR_SW_DBM;
7635 			while (!atomic_fcmpset_64(pte, &oldpte,
7636 			    (oldpte | set) & ~clear))
7637 				cpu_spinwait();
7638 
7639 			if ((oldpte & mask) == val)
7640 				vm_page_dirty(m);
7641 			pmap_invalidate_page(pmap, pv->pv_va, true);
7642 		}
7643 		PMAP_UNLOCK(pmap);
7644 	}
7645 	rw_wunlock(lock);
7646 	vm_page_aflag_clear(m, PGA_WRITEABLE);
7647 }
7648 
7649 /*
7650  *	pmap_ts_referenced:
7651  *
7652  *	Return a count of reference bits for a page, clearing those bits.
7653  *	It is not necessary for every reference bit to be cleared, but it
7654  *	is necessary that 0 only be returned when there are truly no
7655  *	reference bits set.
7656  *
7657  *	As an optimization, update the page's dirty field if a modified bit is
7658  *	found while counting reference bits.  This opportunistic update can be
7659  *	performed at low cost and can eliminate the need for some future calls
7660  *	to pmap_is_modified().  However, since this function stops after
7661  *	finding PMAP_TS_REFERENCED_MAX reference bits, it may not detect some
7662  *	dirty pages.  Those dirty pages will only be detected by a future call
7663  *	to pmap_is_modified().
7664  */
7665 int
7666 pmap_ts_referenced(vm_page_t m)
7667 {
7668 	struct md_page *pvh;
7669 	pv_entry_t pv, pvf;
7670 	pmap_t pmap;
7671 	struct rwlock *lock;
7672 	pt_entry_t *pte, tpte;
7673 	vm_offset_t va;
7674 	vm_paddr_t pa;
7675 	int cleared, md_gen, not_cleared, pvh_gen;
7676 	struct spglist free;
7677 
7678 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
7679 	    ("pmap_ts_referenced: page %p is not managed", m));
7680 	SLIST_INIT(&free);
7681 	cleared = 0;
7682 	pvh = (m->flags & PG_FICTITIOUS) != 0 ? &pv_dummy : page_to_pvh(m);
7683 	lock = VM_PAGE_TO_PV_LIST_LOCK(m);
7684 	rw_wlock(lock);
7685 retry:
7686 	not_cleared = 0;
7687 	if ((pvf = TAILQ_FIRST(&pvh->pv_list)) == NULL)
7688 		goto small_mappings;
7689 	pv = pvf;
7690 	do {
7691 		if (pvf == NULL)
7692 			pvf = pv;
7693 		pmap = PV_PMAP(pv);
7694 		if (!PMAP_TRYLOCK(pmap)) {
7695 			pvh_gen = pvh->pv_gen;
7696 			rw_wunlock(lock);
7697 			PMAP_LOCK(pmap);
7698 			rw_wlock(lock);
7699 			if (pvh_gen != pvh->pv_gen) {
7700 				PMAP_UNLOCK(pmap);
7701 				goto retry;
7702 			}
7703 		}
7704 		va = pv->pv_va;
7705 		pte = pmap_pte_exists(pmap, va, 2, __func__);
7706 		tpte = pmap_load(pte);
7707 		if (pmap_pte_dirty(pmap, tpte)) {
7708 			/*
7709 			 * Although "tpte" is mapping a 2MB page, because
7710 			 * this function is called at a 4KB page granularity,
7711 			 * we only update the 4KB page under test.
7712 			 */
7713 			vm_page_dirty(m);
7714 		}
7715 		if ((tpte & ATTR_AF) != 0) {
7716 			pa = VM_PAGE_TO_PHYS(m);
7717 
7718 			/*
7719 			 * Since this reference bit is shared by 512 4KB pages,
7720 			 * it should not be cleared every time it is tested.
7721 			 * Apply a simple "hash" function on the physical page
7722 			 * number, the virtual superpage number, and the pmap
7723 			 * address to select one 4KB page out of the 512 on
7724 			 * which testing the reference bit will result in
7725 			 * clearing that reference bit.  This function is
7726 			 * designed to avoid the selection of the same 4KB page
7727 			 * for every 2MB page mapping.
7728 			 *
7729 			 * On demotion, a mapping that hasn't been referenced
7730 			 * is simply destroyed.  To avoid the possibility of a
7731 			 * subsequent page fault on a demoted wired mapping,
7732 			 * always leave its reference bit set.  Moreover,
7733 			 * since the superpage is wired, the current state of
7734 			 * its reference bit won't affect page replacement.
7735 			 */
7736 			if ((((pa >> PAGE_SHIFT) ^ (va >> L2_SHIFT) ^
7737 			    (uintptr_t)pmap) & (Ln_ENTRIES - 1)) == 0 &&
7738 			    (tpte & ATTR_SW_WIRED) == 0) {
7739 				pmap_clear_bits(pte, ATTR_AF);
7740 				pmap_invalidate_page(pmap, va, true);
7741 				cleared++;
7742 			} else
7743 				not_cleared++;
7744 		}
7745 		PMAP_UNLOCK(pmap);
7746 		/* Rotate the PV list if it has more than one entry. */
7747 		if (TAILQ_NEXT(pv, pv_next) != NULL) {
7748 			TAILQ_REMOVE(&pvh->pv_list, pv, pv_next);
7749 			TAILQ_INSERT_TAIL(&pvh->pv_list, pv, pv_next);
7750 			pvh->pv_gen++;
7751 		}
7752 		if (cleared + not_cleared >= PMAP_TS_REFERENCED_MAX)
7753 			goto out;
7754 	} while ((pv = TAILQ_FIRST(&pvh->pv_list)) != pvf);
7755 small_mappings:
7756 	if ((pvf = TAILQ_FIRST(&m->md.pv_list)) == NULL)
7757 		goto out;
7758 	pv = pvf;
7759 	do {
7760 		if (pvf == NULL)
7761 			pvf = pv;
7762 		pmap = PV_PMAP(pv);
7763 		if (!PMAP_TRYLOCK(pmap)) {
7764 			pvh_gen = pvh->pv_gen;
7765 			md_gen = m->md.pv_gen;
7766 			rw_wunlock(lock);
7767 			PMAP_LOCK(pmap);
7768 			rw_wlock(lock);
7769 			if (pvh_gen != pvh->pv_gen || md_gen != m->md.pv_gen) {
7770 				PMAP_UNLOCK(pmap);
7771 				goto retry;
7772 			}
7773 		}
7774 		pte = pmap_pte_exists(pmap, pv->pv_va, 3, __func__);
7775 		tpte = pmap_load(pte);
7776 		if (pmap_pte_dirty(pmap, tpte))
7777 			vm_page_dirty(m);
7778 		if ((tpte & ATTR_AF) != 0) {
7779 			if ((tpte & ATTR_SW_WIRED) == 0) {
7780 				/*
7781 				 * Clear the accessed bit in this L3 entry
7782 				 * regardless of the contiguous bit.
7783 				 */
7784 				pmap_clear_bits(pte, ATTR_AF);
7785 				pmap_invalidate_page(pmap, pv->pv_va, true);
7786 				cleared++;
7787 			} else
7788 				not_cleared++;
7789 		} else if ((tpte & ATTR_CONTIGUOUS) != 0 &&
7790 		    (pmap_load_l3c(pte) & ATTR_AF) != 0) {
7791 			/*
7792 			 * An L3C superpage mapping is regarded as accessed
7793 			 * until the accessed bit has been cleared in all
7794 			 * of its constituent entries.
7795 			 */
7796 			not_cleared++;
7797 		}
7798 		PMAP_UNLOCK(pmap);
7799 		/* Rotate the PV list if it has more than one entry. */
7800 		if (TAILQ_NEXT(pv, pv_next) != NULL) {
7801 			TAILQ_REMOVE(&m->md.pv_list, pv, pv_next);
7802 			TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_next);
7803 			m->md.pv_gen++;
7804 		}
7805 	} while ((pv = TAILQ_FIRST(&m->md.pv_list)) != pvf && cleared +
7806 	    not_cleared < PMAP_TS_REFERENCED_MAX);
7807 out:
7808 	rw_wunlock(lock);
7809 	vm_page_free_pages_toq(&free, true);
7810 	return (cleared + not_cleared);
7811 }
7812 
7813 /*
7814  *	Apply the given advice to the specified range of addresses within the
7815  *	given pmap.  Depending on the advice, clear the referenced and/or
7816  *	modified flags in each mapping and set the mapped page's dirty field.
7817  */
7818 void
7819 pmap_advise(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, int advice)
7820 {
7821 	struct rwlock *lock;
7822 	vm_offset_t va, va_next, dva;
7823 	vm_page_t m;
7824 	pd_entry_t *l0, *l1, *l2, oldl2;
7825 	pt_entry_t *l3, *dl3, oldl3;
7826 
7827 	PMAP_ASSERT_STAGE1(pmap);
7828 
7829 	if (advice != MADV_DONTNEED && advice != MADV_FREE)
7830 		return;
7831 
7832 	PMAP_LOCK(pmap);
7833 	for (; sva < eva; sva = va_next) {
7834 		l0 = pmap_l0(pmap, sva);
7835 		if (pmap_load(l0) == 0) {
7836 			va_next = (sva + L0_SIZE) & ~L0_OFFSET;
7837 			if (va_next < sva)
7838 				va_next = eva;
7839 			continue;
7840 		}
7841 
7842 		va_next = (sva + L1_SIZE) & ~L1_OFFSET;
7843 		if (va_next < sva)
7844 			va_next = eva;
7845 		l1 = pmap_l0_to_l1(l0, sva);
7846 		if (pmap_load(l1) == 0)
7847 			continue;
7848 		if ((pmap_load(l1) & ATTR_DESCR_MASK) == L1_BLOCK) {
7849 			PMAP_ASSERT_L1_BLOCKS_SUPPORTED;
7850 			continue;
7851 		}
7852 
7853 		va_next = (sva + L2_SIZE) & ~L2_OFFSET;
7854 		if (va_next < sva)
7855 			va_next = eva;
7856 		l2 = pmap_l1_to_l2(l1, sva);
7857 		oldl2 = pmap_load(l2);
7858 		if (oldl2 == 0)
7859 			continue;
7860 		if ((oldl2 & ATTR_DESCR_MASK) == L2_BLOCK) {
7861 			if ((oldl2 & ATTR_SW_MANAGED) == 0)
7862 				continue;
7863 			lock = NULL;
7864 			if (!pmap_demote_l2_locked(pmap, l2, sva, &lock)) {
7865 				if (lock != NULL)
7866 					rw_wunlock(lock);
7867 
7868 				/*
7869 				 * The 2MB page mapping was destroyed.
7870 				 */
7871 				continue;
7872 			}
7873 
7874 			/*
7875 			 * Unless the page mappings are wired, remove the
7876 			 * mapping to a single page so that a subsequent
7877 			 * access may repromote.  Choosing the last page
7878 			 * within the address range [sva, min(va_next, eva))
7879 			 * generally results in more repromotions.  Since the
7880 			 * underlying page table page is fully populated, this
7881 			 * removal never frees a page table page.
7882 			 */
7883 			if ((oldl2 & ATTR_SW_WIRED) == 0) {
7884 				va = eva;
7885 				if (va > va_next)
7886 					va = va_next;
7887 				va -= PAGE_SIZE;
7888 				KASSERT(va >= sva,
7889 				    ("pmap_advise: no address gap"));
7890 				l3 = pmap_l2_to_l3(l2, va);
7891 				KASSERT(pmap_load(l3) != 0,
7892 				    ("pmap_advise: invalid PTE"));
7893 				pmap_remove_l3(pmap, l3, va, pmap_load(l2),
7894 				    NULL, &lock);
7895 			}
7896 			if (lock != NULL)
7897 				rw_wunlock(lock);
7898 		}
7899 		KASSERT((pmap_load(l2) & ATTR_DESCR_MASK) == L2_TABLE,
7900 		    ("pmap_advise: invalid L2 entry after demotion"));
7901 		if (va_next > eva)
7902 			va_next = eva;
7903 		va = va_next;
7904 		for (l3 = pmap_l2_to_l3(l2, sva); sva != va_next; l3++,
7905 		    sva += L3_SIZE) {
7906 			oldl3 = pmap_load(l3);
7907 			if ((oldl3 & (ATTR_SW_MANAGED | ATTR_DESCR_MASK)) !=
7908 			    (ATTR_SW_MANAGED | L3_PAGE))
7909 				goto maybe_invlrng;
7910 			else if (pmap_pte_dirty(pmap, oldl3)) {
7911 				if (advice == MADV_DONTNEED) {
7912 					/*
7913 					 * Future calls to pmap_is_modified()
7914 					 * can be avoided by making the page
7915 					 * dirty now.
7916 					 */
7917 					m = PTE_TO_VM_PAGE(oldl3);
7918 					vm_page_dirty(m);
7919 				}
7920 				if ((oldl3 & ATTR_CONTIGUOUS) != 0) {
7921 					/*
7922 					 * Unconditionally demote the L3C
7923 					 * superpage because we do not allow
7924 					 * writeable, clean superpages.
7925 					 */
7926 					(void)pmap_demote_l3c(pmap, l3, sva);
7927 
7928 					/*
7929                                          * Destroy the final mapping before the
7930                                          * next L3C boundary or va_next,
7931 					 * whichever comes first, so that a
7932 					 * subsequent access may act as a
7933 					 * repromotion trigger.
7934 					 */
7935                                         if ((oldl3 & ATTR_SW_WIRED) == 0) {
7936 						dva = MIN((sva & ~L3C_OFFSET) +
7937 						    L3C_SIZE - PAGE_SIZE,
7938 						    va_next - PAGE_SIZE);
7939 						dl3 = pmap_l2_to_l3(l2, dva);
7940 						KASSERT(pmap_load(dl3) != 0,
7941 						    ("pmap_advise: invalid PTE"));
7942 						lock = NULL;
7943 						pmap_remove_l3(pmap, dl3, dva,
7944 						    pmap_load(l2), NULL, &lock);
7945 						if (lock != NULL)
7946 							rw_wunlock(lock);
7947 					}
7948 
7949 					/*
7950 					 * The L3 entry's accessed bit may have
7951 					 * changed.
7952 					 */
7953 					oldl3 = pmap_load(l3);
7954 				}
7955 
7956 				/*
7957 				 * Check that we did not just destroy this entry so
7958 				 * we avoid corrupting the page able.
7959 				 */
7960 				if (oldl3 != 0) {
7961 					while (!atomic_fcmpset_long(l3, &oldl3,
7962 					    (oldl3 & ~ATTR_AF) |
7963 					    ATTR_S1_AP(ATTR_S1_AP_RO)))
7964 						cpu_spinwait();
7965 				}
7966 			} else if ((oldl3 & ATTR_AF) != 0) {
7967 				/*
7968 				 * Clear the accessed bit in this L3 entry
7969 				 * regardless of the contiguous bit.
7970 				 */
7971 				pmap_clear_bits(l3, ATTR_AF);
7972 			} else
7973 				goto maybe_invlrng;
7974 			if (va == va_next)
7975 				va = sva;
7976 			continue;
7977 maybe_invlrng:
7978 			if (va != va_next) {
7979 				pmap_s1_invalidate_range(pmap, va, sva, true);
7980 				va = va_next;
7981 			}
7982 		}
7983 		if (va != va_next)
7984 			pmap_s1_invalidate_range(pmap, va, sva, true);
7985 	}
7986 	PMAP_UNLOCK(pmap);
7987 }
7988 
7989 /*
7990  *	Clear the modify bits on the specified physical page.
7991  */
7992 void
7993 pmap_clear_modify(vm_page_t m)
7994 {
7995 	struct md_page *pvh;
7996 	struct rwlock *lock;
7997 	pmap_t pmap;
7998 	pv_entry_t next_pv, pv;
7999 	pd_entry_t *l2, oldl2;
8000 	pt_entry_t *l3, oldl3;
8001 	vm_offset_t va;
8002 	int md_gen, pvh_gen;
8003 
8004 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
8005 	    ("pmap_clear_modify: page %p is not managed", m));
8006 	vm_page_assert_busied(m);
8007 
8008 	if (!pmap_page_is_write_mapped(m))
8009 		return;
8010 	pvh = (m->flags & PG_FICTITIOUS) != 0 ? &pv_dummy : page_to_pvh(m);
8011 	lock = VM_PAGE_TO_PV_LIST_LOCK(m);
8012 	rw_wlock(lock);
8013 restart:
8014 	TAILQ_FOREACH_SAFE(pv, &pvh->pv_list, pv_next, next_pv) {
8015 		pmap = PV_PMAP(pv);
8016 		PMAP_ASSERT_STAGE1(pmap);
8017 		if (!PMAP_TRYLOCK(pmap)) {
8018 			pvh_gen = pvh->pv_gen;
8019 			rw_wunlock(lock);
8020 			PMAP_LOCK(pmap);
8021 			rw_wlock(lock);
8022 			if (pvh_gen != pvh->pv_gen) {
8023 				PMAP_UNLOCK(pmap);
8024 				goto restart;
8025 			}
8026 		}
8027 		va = pv->pv_va;
8028 		l2 = pmap_l2(pmap, va);
8029 		oldl2 = pmap_load(l2);
8030 		/* If oldl2 has ATTR_SW_DBM set, then it is also dirty. */
8031 		if ((oldl2 & ATTR_SW_DBM) != 0 &&
8032 		    pmap_demote_l2_locked(pmap, l2, va, &lock) &&
8033 		    (oldl2 & ATTR_SW_WIRED) == 0) {
8034 			/*
8035 			 * Write protect the mapping to a single page so that
8036 			 * a subsequent write access may repromote.
8037 			 */
8038 			va += VM_PAGE_TO_PHYS(m) - PTE_TO_PHYS(oldl2);
8039 			l3 = pmap_l2_to_l3(l2, va);
8040 			oldl3 = pmap_load(l3);
8041 			while (!atomic_fcmpset_long(l3, &oldl3,
8042 			    (oldl3 & ~ATTR_SW_DBM) | ATTR_S1_AP(ATTR_S1_AP_RO)))
8043 				cpu_spinwait();
8044 			vm_page_dirty(m);
8045 			pmap_s1_invalidate_page(pmap, va, true);
8046 		}
8047 		PMAP_UNLOCK(pmap);
8048 	}
8049 	TAILQ_FOREACH(pv, &m->md.pv_list, pv_next) {
8050 		pmap = PV_PMAP(pv);
8051 		PMAP_ASSERT_STAGE1(pmap);
8052 		if (!PMAP_TRYLOCK(pmap)) {
8053 			md_gen = m->md.pv_gen;
8054 			pvh_gen = pvh->pv_gen;
8055 			rw_wunlock(lock);
8056 			PMAP_LOCK(pmap);
8057 			rw_wlock(lock);
8058 			if (pvh_gen != pvh->pv_gen || md_gen != m->md.pv_gen) {
8059 				PMAP_UNLOCK(pmap);
8060 				goto restart;
8061 			}
8062 		}
8063 		l2 = pmap_l2(pmap, pv->pv_va);
8064 		l3 = pmap_l2_to_l3(l2, pv->pv_va);
8065 		oldl3 = pmap_load(l3);
8066 		KASSERT((oldl3 & ATTR_CONTIGUOUS) == 0 ||
8067 		    (oldl3 & (ATTR_SW_DBM | ATTR_S1_AP_RW_BIT)) !=
8068 		    (ATTR_SW_DBM | ATTR_S1_AP(ATTR_S1_AP_RO)),
8069 		    ("writeable L3C superpage not dirty"));
8070 		if ((oldl3 & (ATTR_S1_AP_RW_BIT | ATTR_SW_DBM)) == ATTR_SW_DBM) {
8071 			if ((oldl3 & ATTR_CONTIGUOUS) != 0)
8072 				(void)pmap_demote_l3c(pmap, l3, pv->pv_va);
8073 			pmap_set_bits(l3, ATTR_S1_AP(ATTR_S1_AP_RO));
8074 			pmap_s1_invalidate_page(pmap, pv->pv_va, true);
8075 		}
8076 		PMAP_UNLOCK(pmap);
8077 	}
8078 	rw_wunlock(lock);
8079 }
8080 
8081 void *
8082 pmap_mapbios(vm_paddr_t pa, vm_size_t size)
8083 {
8084 	struct pmap_preinit_mapping *ppim;
8085 	vm_offset_t va, offset;
8086 	pd_entry_t old_l2e, *pde;
8087 	pt_entry_t *l2;
8088 	int i, lvl, l2_blocks, free_l2_count, start_idx;
8089 
8090 	/* Use the DMAP region if we can */
8091 	if (PHYS_IN_DMAP(pa) && PHYS_IN_DMAP(pa + size - 1) &&
8092 	    pmap_kmapped_range(PHYS_TO_DMAP(pa), size))
8093 		return (PHYS_TO_DMAP(pa));
8094 
8095 	if (!vm_initialized) {
8096 		/*
8097 		 * No L3 ptables so map entire L2 blocks where start VA is:
8098 		 * 	preinit_map_va + start_idx * L2_SIZE
8099 		 * There may be duplicate mappings (multiple VA -> same PA) but
8100 		 * ARM64 dcache is always PIPT so that's acceptable.
8101 		 */
8102 		 if (size == 0)
8103 			 return (NULL);
8104 
8105 		 /* Calculate how many L2 blocks are needed for the mapping */
8106 		l2_blocks = (roundup2(pa + size, L2_SIZE) -
8107 		    rounddown2(pa, L2_SIZE)) >> L2_SHIFT;
8108 
8109 		offset = pa & L2_OFFSET;
8110 
8111 		if (preinit_map_va == 0)
8112 			return (NULL);
8113 
8114 		/* Map 2MiB L2 blocks from reserved VA space */
8115 
8116 		free_l2_count = 0;
8117 		start_idx = -1;
8118 		/* Find enough free contiguous VA space */
8119 		for (i = 0; i < PMAP_PREINIT_MAPPING_COUNT; i++) {
8120 			ppim = pmap_preinit_mapping + i;
8121 			if (free_l2_count > 0 && ppim->pa != 0) {
8122 				/* Not enough space here */
8123 				free_l2_count = 0;
8124 				start_idx = -1;
8125 				continue;
8126 			}
8127 
8128 			if (ppim->pa == 0) {
8129 				/* Free L2 block */
8130 				if (start_idx == -1)
8131 					start_idx = i;
8132 				free_l2_count++;
8133 				if (free_l2_count == l2_blocks)
8134 					break;
8135 			}
8136 		}
8137 		if (free_l2_count != l2_blocks)
8138 			panic("%s: too many preinit mappings", __func__);
8139 
8140 		va = preinit_map_va + (start_idx * L2_SIZE);
8141 		for (i = start_idx; i < start_idx + l2_blocks; i++) {
8142 			/* Mark entries as allocated */
8143 			ppim = pmap_preinit_mapping + i;
8144 			ppim->pa = pa;
8145 			ppim->va = (char *)va + offset;
8146 			ppim->size = size;
8147 		}
8148 
8149 		/* Map L2 blocks */
8150 		pa = rounddown2(pa, L2_SIZE);
8151 		old_l2e = 0;
8152 		for (i = 0; i < l2_blocks; i++) {
8153 			pde = pmap_pde(kernel_pmap, va, &lvl);
8154 			KASSERT(pde != NULL,
8155 			    ("pmap_mapbios: Invalid page entry, va: 0x%lx",
8156 			    va));
8157 			KASSERT(lvl == 1,
8158 			    ("pmap_mapbios: Invalid level %d", lvl));
8159 
8160 			/* Insert L2_BLOCK */
8161 			l2 = pmap_l1_to_l2(pde, va);
8162 			old_l2e |= pmap_load_store(l2,
8163 			    PHYS_TO_PTE(pa) | ATTR_AF | pmap_sh_attr |
8164 			    ATTR_S1_XN | ATTR_KERN_GP |
8165 			    ATTR_S1_IDX(VM_MEMATTR_WRITE_BACK) | L2_BLOCK);
8166 
8167 			va += L2_SIZE;
8168 			pa += L2_SIZE;
8169 		}
8170 		if ((old_l2e & ATTR_DESCR_VALID) != 0)
8171 			pmap_s1_invalidate_all_kernel();
8172 		else {
8173 			/*
8174 			 * Because the old entries were invalid and the new
8175 			 * mappings are not executable, an isb is not required.
8176 			 */
8177 			dsb(ishst);
8178 		}
8179 
8180 		va = preinit_map_va + (start_idx * L2_SIZE);
8181 
8182 	} else {
8183 		/* kva_alloc may be used to map the pages */
8184 		offset = pa & PAGE_MASK;
8185 		size = round_page(offset + size);
8186 
8187 		va = (vm_offset_t)kva_alloc(size);
8188 		if (va == 0)
8189 			panic("%s: Couldn't allocate KVA", __func__);
8190 
8191 		pde = pmap_pde(kernel_pmap, va, &lvl);
8192 		KASSERT(lvl == 2, ("pmap_mapbios: Invalid level %d", lvl));
8193 
8194 		/* L3 table is linked */
8195 		va = trunc_page(va);
8196 		pa = trunc_page(pa);
8197 		pmap_kenter(va, size, pa, memory_mapping_mode(pa));
8198 	}
8199 
8200 	return ((void *)(va + offset));
8201 }
8202 
8203 void
8204 pmap_unmapbios(void *p, vm_size_t size)
8205 {
8206 	struct pmap_preinit_mapping *ppim;
8207 	char *va;
8208 	vm_offset_t offset, va_trunc;
8209 	pd_entry_t *pde;
8210 	pt_entry_t *l2;
8211 	int error __diagused, i, lvl, l2_blocks, block;
8212 	bool preinit_map;
8213 
8214 	va = p;
8215 	if (VIRT_IN_DMAP(va)) {
8216 		KASSERT(VIRT_IN_DMAP(va + size - 1),
8217 		    ("%s: End address not in DMAP region: %p", __func__,
8218 		    va + size - 1));
8219 		/* Ensure the attributes are as expected for the DMAP region */
8220 		PMAP_LOCK(kernel_pmap);
8221 		error = pmap_change_props_locked(va, size,
8222 		    PROT_READ | PROT_WRITE, VM_MEMATTR_DEFAULT, -1, false);
8223 		PMAP_UNLOCK(kernel_pmap);
8224 		KASSERT(error == 0, ("%s: Failed to reset DMAP attributes: %d",
8225 		    __func__, error));
8226 
8227 		return;
8228 	}
8229 
8230 	l2_blocks =
8231 	   (roundup2(va + size, L2_SIZE) - rounddown2(va, L2_SIZE)) >> L2_SHIFT;
8232 	KASSERT(l2_blocks > 0, ("pmap_unmapbios: invalid size %lx", size));
8233 
8234 	/* Remove preinit mapping */
8235 	preinit_map = false;
8236 	block = 0;
8237 	for (i = 0; i < PMAP_PREINIT_MAPPING_COUNT; i++) {
8238 		ppim = pmap_preinit_mapping + i;
8239 		if (ppim->va == va) {
8240 			KASSERT(ppim->size == size,
8241 			    ("pmap_unmapbios: size mismatch"));
8242 			ppim->va = NULL;
8243 			ppim->pa = 0;
8244 			ppim->size = 0;
8245 			preinit_map = true;
8246 			offset = block * L2_SIZE;
8247 			va_trunc = rounddown2((vm_offset_t)va, L2_SIZE) +
8248 			    offset;
8249 
8250 			/* Remove L2_BLOCK */
8251 			pde = pmap_pde(kernel_pmap, va_trunc, &lvl);
8252 			KASSERT(pde != NULL,
8253 			    ("pmap_unmapbios: Invalid page entry, va: 0x%lx",
8254 			    va_trunc));
8255 			l2 = pmap_l1_to_l2(pde, va_trunc);
8256 			pmap_clear(l2);
8257 
8258 			if (block == (l2_blocks - 1))
8259 				break;
8260 			block++;
8261 		}
8262 	}
8263 	if (preinit_map) {
8264 		pmap_s1_invalidate_all_kernel();
8265 		return;
8266 	}
8267 
8268 	/* Unmap the pages reserved with kva_alloc. */
8269 	if (vm_initialized) {
8270 		offset = (vm_offset_t)va & PAGE_MASK;
8271 		size = round_page(offset + size);
8272 		va = trunc_page(va);
8273 
8274 		/* Unmap and invalidate the pages */
8275 		pmap_kremove_device((vm_offset_t)va, size);
8276 
8277 		kva_free(va, size);
8278 	}
8279 }
8280 
8281 /*
8282  * Sets the memory attribute for the specified page.
8283  */
8284 void
8285 pmap_page_set_memattr(vm_page_t m, vm_memattr_t ma)
8286 {
8287 	if (m->md.pv_memattr == ma)
8288 		return;
8289 
8290 	m->md.pv_memattr = ma;
8291 
8292 	/*
8293 	 * If "m" is a normal page, update its direct mapping.  This update
8294 	 * can be relied upon to perform any cache operations that are
8295 	 * required for data coherence.
8296 	 */
8297 	if ((m->flags & PG_FICTITIOUS) == 0 &&
8298 	    pmap_change_attr(VM_PAGE_TO_DMAP(m), PAGE_SIZE,
8299 	    m->md.pv_memattr) != 0)
8300 		panic("memory attribute change on the direct map failed");
8301 }
8302 
8303 /*
8304  * Changes the specified virtual address range's memory type to that given by
8305  * the parameter "mode".  The specified virtual address range must be
8306  * completely contained within either the direct map or the kernel map.  If
8307  * the virtual address range is contained within the kernel map, then the
8308  * memory type for each of the corresponding ranges of the direct map is also
8309  * changed.  (The corresponding ranges of the direct map are those ranges that
8310  * map the same physical pages as the specified virtual address range.)  These
8311  * changes to the direct map are necessary because Intel describes the
8312  * behavior of their processors as "undefined" if two or more mappings to the
8313  * same physical page have different memory types.
8314  *
8315  * Returns zero if the change completed successfully, and either EINVAL or
8316  * ENOMEM if the change failed.  Specifically, EINVAL is returned if some part
8317  * of the virtual address range was not mapped, and ENOMEM is returned if
8318  * there was insufficient memory available to complete the change.  In the
8319  * latter case, the memory type may have been changed on some part of the
8320  * virtual address range or the direct map.
8321  */
8322 int
8323 pmap_change_attr(void *va, vm_size_t size, int mode)
8324 {
8325 	int error;
8326 
8327 	PMAP_LOCK(kernel_pmap);
8328 	error = pmap_change_props_locked(va, size, PROT_NONE, mode, -1, false);
8329 	PMAP_UNLOCK(kernel_pmap);
8330 	return (error);
8331 }
8332 
8333 int
8334 pmap_change_dmap_attr(int mode)
8335 {
8336 	int error;
8337 
8338 	KASSERT(mode == VM_MEMATTR_WRITE_BACK ||
8339 	    mode == VM_MEMATTR_TAGGED,
8340 	    ("%s: mode %d must be compatible with write-back", __func__, mode));
8341 
8342 	PMAP_LOCK(kernel_pmap);
8343 	error = pmap_change_props_locked((void *)DMAP_MIN_ADDRESS,
8344 	    dmap_max_addr - DMAP_MIN_ADDRESS, PROT_NONE, mode, dmap_attr, true);
8345 	if (error == 0)
8346 		dmap_attr = mode;
8347 	PMAP_UNLOCK(kernel_pmap);
8348 	return (error);
8349 }
8350 
8351 /*
8352  * Changes the specified virtual address range's protections to those
8353  * specified by "prot".  Like pmap_change_attr(), protections for aliases
8354  * in the direct map are updated as well.  Protections on aliasing mappings may
8355  * be a subset of the requested protections; for example, mappings in the direct
8356  * map are never executable.
8357  */
8358 int
8359 pmap_change_prot(void *va, vm_size_t size, vm_prot_t prot)
8360 {
8361 	int error;
8362 
8363 	/* Only supported within the kernel map. */
8364 	if ((vm_offset_t)va < VM_MIN_KERNEL_ADDRESS)
8365 		return (EINVAL);
8366 
8367 	PMAP_LOCK(kernel_pmap);
8368 	error = pmap_change_props_locked(va, size, prot, -1, -1, false);
8369 	PMAP_UNLOCK(kernel_pmap);
8370 	return (error);
8371 }
8372 
8373 static int
8374 pmap_change_props_locked(void *addr, vm_size_t size, vm_prot_t prot,
8375     int mode, int old_mode, bool skip_unmapped)
8376 {
8377 	vm_offset_t base, offset, tmpva, va;
8378 	vm_size_t pte_size;
8379 	vm_paddr_t pa;
8380 	pt_entry_t pte, *ptep, *newpte;
8381 	pt_entry_t bits, mask, old_mode_bits, old_mode_mask;
8382 	char *tmpptep;
8383 	int lvl, rv;
8384 
8385 	PMAP_LOCK_ASSERT(kernel_pmap, MA_OWNED);
8386 	va = (vm_offset_t)addr;
8387 	base = trunc_page(va);
8388 	offset = va & PAGE_MASK;
8389 	size = round_page(offset + size);
8390 
8391 	if (!VIRT_IN_DMAP(base) &&
8392 	    !(base >= VM_MIN_KERNEL_ADDRESS && base < VM_MAX_KERNEL_ADDRESS))
8393 		return (EINVAL);
8394 
8395 	bits = old_mode_bits = 0;
8396 	mask = old_mode_mask = 0;
8397 	if (mode != -1) {
8398 		bits = ATTR_S1_IDX(mode);
8399 		mask = ATTR_S1_IDX_MASK;
8400 		if (mode == VM_MEMATTR_DEVICE) {
8401 			mask |= ATTR_S1_XN;
8402 			bits |= ATTR_S1_XN;
8403 		}
8404 	}
8405 	if (old_mode != -1) {
8406 		old_mode_bits = ATTR_S1_IDX(old_mode);
8407 		old_mode_mask = ATTR_S1_IDX_MASK;
8408 	}
8409 	if (prot != VM_PROT_NONE) {
8410 		/* Don't mark the DMAP as executable. It never is on arm64. */
8411 		if (VIRT_IN_DMAP(base)) {
8412 			prot &= ~VM_PROT_EXECUTE;
8413 			/*
8414 			 * XXX Mark the DMAP as writable for now. We rely
8415 			 * on this in ddb & dtrace to insert breakpoint
8416 			 * instructions.
8417 			 */
8418 			prot |= VM_PROT_WRITE;
8419 		}
8420 
8421 		if ((prot & VM_PROT_WRITE) == 0) {
8422 			bits |= ATTR_S1_AP(ATTR_S1_AP_RO);
8423 		}
8424 		if ((prot & VM_PROT_EXECUTE) == 0) {
8425 			bits |= ATTR_S1_PXN;
8426 		}
8427 		bits |= ATTR_S1_UXN;
8428 		mask |= ATTR_S1_AP_MASK | ATTR_S1_XN;
8429 	}
8430 
8431 	for (tmpva = base; tmpva < base + size; ) {
8432 		ptep = pmap_pte(kernel_pmap, tmpva, &lvl);
8433 		if (ptep == NULL && !skip_unmapped) {
8434 			return (EINVAL);
8435 		} else if ((ptep == NULL && skip_unmapped) ||
8436 		    (pmap_load(ptep) & mask) == bits ||
8437 		    (pmap_load(ptep) & old_mode_mask) != old_mode_bits) {
8438 			/*
8439 			 * We already have one of the following meaning
8440 			 * we can skip this memory region::
8441 			 *  - No memory mapped at this address
8442 			 *  - The new attributes are already set
8443 			 *  - The expected attributes are incorrect
8444 			 */
8445 			switch (lvl) {
8446 			default:
8447 				panic("Invalid DMAP table level: %d\n", lvl);
8448 			case 1:
8449 				tmpva = (tmpva & ~L1_OFFSET) + L1_SIZE;
8450 				break;
8451 			case 2:
8452 				tmpva = (tmpva & ~L2_OFFSET) + L2_SIZE;
8453 				break;
8454 			case 3:
8455 				tmpva += PAGE_SIZE;
8456 				break;
8457 			}
8458 		} else {
8459 			/* We can't demote/promote this entry */
8460 			MPASS((pmap_load(ptep) & ATTR_SW_NO_PROMOTE) == 0);
8461 
8462 			/*
8463 			 * Find the entry and demote it if the requested change
8464 			 * only applies to part of the address range mapped by
8465 			 * the entry.
8466 			 */
8467 			switch (lvl) {
8468 			default:
8469 				panic("Invalid DMAP table level: %d\n", lvl);
8470 			case 1:
8471 				PMAP_ASSERT_L1_BLOCKS_SUPPORTED;
8472 				if ((tmpva & L1_OFFSET) == 0 &&
8473 				    (base + size - tmpva) >= L1_SIZE) {
8474 					pte_size = L1_SIZE;
8475 					break;
8476 				}
8477 				newpte = pmap_demote_l1(kernel_pmap, ptep,
8478 				    tmpva & ~L1_OFFSET);
8479 				if (newpte == NULL)
8480 					return (EINVAL);
8481 				ptep = pmap_l1_to_l2(ptep, tmpva);
8482 				/* FALLTHROUGH */
8483 			case 2:
8484 				if ((pmap_load(ptep) & ATTR_CONTIGUOUS) != 0) {
8485 					if ((tmpva & L2C_OFFSET) == 0 &&
8486 					    (base + size - tmpva) >= L2C_SIZE) {
8487 						pte_size = L2C_SIZE;
8488 						break;
8489 					}
8490 					if (!pmap_demote_l2c(kernel_pmap, ptep,
8491 					    tmpva))
8492 						return (EINVAL);
8493 				}
8494 				if ((tmpva & L2_OFFSET) == 0 &&
8495 				    (base + size - tmpva) >= L2_SIZE) {
8496 					pte_size = L2_SIZE;
8497 					break;
8498 				}
8499 				newpte = pmap_demote_l2(kernel_pmap, ptep,
8500 				    tmpva);
8501 				if (newpte == NULL)
8502 					return (EINVAL);
8503 				ptep = pmap_l2_to_l3(ptep, tmpva);
8504 				/* FALLTHROUGH */
8505 			case 3:
8506 				if ((pmap_load(ptep) & ATTR_CONTIGUOUS) != 0) {
8507 					if ((tmpva & L3C_OFFSET) == 0 &&
8508 					    (base + size - tmpva) >= L3C_SIZE) {
8509 						pte_size = L3C_SIZE;
8510 						break;
8511 					}
8512 					if (!pmap_demote_l3c(kernel_pmap, ptep,
8513 					    tmpva))
8514 						return (EINVAL);
8515 				}
8516 				pte_size = PAGE_SIZE;
8517 				break;
8518 			}
8519 
8520 			tmpptep = 0;
8521 			if (tmpva <= (vm_offset_t)ptep &&
8522 			    tmpva + pte_size > (vm_offset_t)ptep) {
8523 				vm_paddr_t pte_pa;
8524 
8525 				mtx_lock(&cmap_lock);
8526 				tmpptep = cmap1_addr;
8527 				pte_pa = DMAP_TO_PHYS((vm_offset_t)ptep);
8528 				pmap_store(cmap1_pte, ATTR_AF |
8529 				    pmap_sh_attr | ATTR_S1_AP(ATTR_S1_AP_RW) |
8530 				    ATTR_S1_XN | ATTR_KERN_GP |
8531 				    ATTR_S1_IDX(VM_MEMATTR_WRITE_BACK) |
8532 				    PHYS_TO_PTE(pte_pa &~L3_OFFSET) | L3_PAGE);
8533 				dsb(ishst);
8534 				ptep = (pt_entry_t *)(tmpptep +
8535 				    ((vm_offset_t)ptep & PAGE_MASK));
8536 			}
8537 
8538 			/* Update the entry */
8539 			pte = pmap_load(ptep);
8540 			pte &= ~mask;
8541 			pte |= bits;
8542 
8543 			switch (pte_size) {
8544 			case L2C_SIZE:
8545 				pmap_update_strided(kernel_pmap, ptep, ptep +
8546 				    L2C_ENTRIES, pte, tmpva, L2_SIZE, L2C_SIZE);
8547 				break;
8548 			case L3C_SIZE:
8549 				pmap_update_strided(kernel_pmap, ptep, ptep +
8550 				    L3C_ENTRIES, pte, tmpva, L3_SIZE, L3C_SIZE);
8551 				break;
8552 			default:
8553 				/*
8554 				 * We are updating a single block or page entry,
8555 				 * so regardless of pte_size pass PAGE_SIZE in
8556 				 * order that a single TLB invalidation is
8557 				 * performed.
8558 				 */
8559 				pmap_update_entry(kernel_pmap, ptep, pte, tmpva,
8560 				    PAGE_SIZE);
8561 				break;
8562 			}
8563 
8564 			if (tmpptep != 0) {
8565 				pmap_clear(cmap1_pte);
8566 				pmap_s1_invalidate_page(kernel_pmap,
8567 				    (vm_offset_t)tmpptep, true);
8568 				mtx_unlock(&cmap_lock);
8569 			}
8570 
8571 			pa = PTE_TO_PHYS(pte);
8572 			if (!VIRT_IN_DMAP(tmpva) && PHYS_IN_DMAP(pa)) {
8573 				int dmap_mode;
8574 
8575 				/*
8576 				 * When booting on HW with MTE enabled we may
8577 				 * need to swap to a tagged type for the DMAP
8578 				 * to allow tags to be set through it.
8579 				 */
8580 				if (mode == VM_MEMATTR_WRITE_BACK)
8581 					dmap_mode = dmap_attr;
8582 				else
8583 					dmap_mode = mode;
8584 
8585 				/*
8586 				 * Keep the DMAP memory in sync.
8587 				 */
8588 				rv = pmap_change_props_locked(
8589 				    PHYS_TO_DMAP(pa), pte_size,
8590 				    prot, dmap_mode, old_mode, true);
8591 				if (rv != 0)
8592 					return (rv);
8593 			}
8594 
8595 			/*
8596 			 * If moving to a non-cacheable entry flush
8597 			 * the cache.
8598 			 */
8599 			if (mode == VM_MEMATTR_UNCACHEABLE)
8600 				cpu_dcache_wbinv_range((void *)tmpva, pte_size);
8601 			tmpva += pte_size;
8602 		}
8603 	}
8604 
8605 	return (0);
8606 }
8607 
8608 /*
8609  * Create an L2 table to map all addresses within an L1 mapping.
8610  */
8611 static pt_entry_t *
8612 pmap_demote_l1(pmap_t pmap, pt_entry_t *l1, vm_offset_t va)
8613 {
8614 	pt_entry_t *l2, newl2, oldl1;
8615 	char *tmpl1;
8616 	vm_paddr_t l2phys, phys;
8617 	vm_page_t ml2;
8618 	int i;
8619 
8620 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
8621 	oldl1 = pmap_load(l1);
8622 	PMAP_ASSERT_L1_BLOCKS_SUPPORTED;
8623 	KASSERT((oldl1 & ATTR_DESCR_MASK) == L1_BLOCK,
8624 	    ("pmap_demote_l1: Demoting a non-block entry"));
8625 	KASSERT((va & L1_OFFSET) == 0,
8626 	    ("pmap_demote_l1: Invalid virtual address %#lx", va));
8627 	KASSERT((oldl1 & ATTR_SW_MANAGED) == 0,
8628 	    ("pmap_demote_l1: Level 1 table shouldn't be managed"));
8629 	KASSERT((oldl1 & ATTR_SW_NO_PROMOTE) == 0,
8630 	    ("pmap_demote_l1: Demoting entry with no-demote flag set"));
8631 
8632 	tmpl1 = NULL;
8633 	if (va <= (vm_offset_t)l1 && va + L1_SIZE > (vm_offset_t)l1) {
8634 		tmpl1 = kva_alloc(PAGE_SIZE);
8635 		if (tmpl1 == NULL)
8636 			return (NULL);
8637 	}
8638 
8639 	if ((ml2 = vm_page_alloc_noobj(VM_ALLOC_INTERRUPT | VM_ALLOC_WIRED)) ==
8640 	    NULL) {
8641 		CTR2(KTR_PMAP, "pmap_demote_l1: failure for va %#lx"
8642 		    " in pmap %p", va, pmap);
8643 		l2 = NULL;
8644 		goto fail;
8645 	}
8646 
8647 	l2phys = VM_PAGE_TO_PHYS(ml2);
8648 	l2 = PHYS_TO_DMAP(l2phys);
8649 
8650 	/* Address the range points at */
8651 	phys = PTE_TO_PHYS(oldl1);
8652 	/* The attributed from the old l1 table to be copied */
8653 	newl2 = oldl1 & ATTR_MASK;
8654 
8655 	/* Create the new entries */
8656 	newl2 |= ATTR_CONTIGUOUS;
8657 	for (i = 0; i < Ln_ENTRIES; i++) {
8658 		l2[i] = newl2 | phys;
8659 		phys += L2_SIZE;
8660 	}
8661 	KASSERT(l2[0] == (ATTR_CONTIGUOUS | (oldl1 & ~ATTR_DESCR_MASK) |
8662 	    L2_BLOCK), ("Invalid l2 page (%lx != %lx)", l2[0],
8663 	    ATTR_CONTIGUOUS | (oldl1 & ~ATTR_DESCR_MASK) | L2_BLOCK));
8664 
8665 	if (tmpl1 != NULL) {
8666 		pmap_kenter((vm_offset_t)tmpl1, PAGE_SIZE,
8667 		    DMAP_TO_PHYS(l1) & ~L3_OFFSET,
8668 		    VM_MEMATTR_WRITE_BACK);
8669 		l1 = (pt_entry_t *)(tmpl1 + ((vm_offset_t)l1 & PAGE_MASK));
8670 	}
8671 
8672 	pmap_update_entry(pmap, l1, l2phys | L1_TABLE, va, PAGE_SIZE);
8673 
8674 	counter_u64_add(pmap_l1_demotions, 1);
8675 fail:
8676 	if (tmpl1 != NULL) {
8677 		pmap_kremove((vm_offset_t)tmpl1);
8678 		kva_free(tmpl1, PAGE_SIZE);
8679 	}
8680 
8681 	return (l2);
8682 }
8683 
8684 static void
8685 pmap_fill_l3(pt_entry_t *firstl3, pt_entry_t newl3)
8686 {
8687 	pt_entry_t *l3;
8688 
8689 	for (l3 = firstl3; l3 - firstl3 < Ln_ENTRIES; l3++) {
8690 		*l3 = newl3;
8691 		newl3 += L3_SIZE;
8692 	}
8693 }
8694 
8695 static void
8696 pmap_demote_l2_check(pt_entry_t *firstl3p __unused, pt_entry_t newl3e __unused)
8697 {
8698 #ifdef INVARIANTS
8699 #ifdef DIAGNOSTIC
8700 	pt_entry_t *xl3p, *yl3p;
8701 
8702 	for (xl3p = firstl3p; xl3p < firstl3p + Ln_ENTRIES;
8703 	    xl3p++, newl3e += PAGE_SIZE) {
8704 		if (PTE_TO_PHYS(pmap_load(xl3p)) != PTE_TO_PHYS(newl3e)) {
8705 			printf("pmap_demote_l2: xl3e %zd and newl3e map "
8706 			    "different pages: found %#lx, expected %#lx\n",
8707 			    xl3p - firstl3p, pmap_load(xl3p), newl3e);
8708 			printf("page table dump\n");
8709 			for (yl3p = firstl3p; yl3p < firstl3p + Ln_ENTRIES;
8710 			    yl3p++) {
8711 				printf("%zd %#lx\n", yl3p - firstl3p,
8712 				    pmap_load(yl3p));
8713 			}
8714 			panic("firstpte");
8715 		}
8716 	}
8717 #else
8718 	KASSERT(PTE_TO_PHYS(pmap_load(firstl3p)) == PTE_TO_PHYS(newl3e),
8719 	    ("pmap_demote_l2: firstl3 and newl3e map different physical"
8720 	    " addresses"));
8721 #endif
8722 #endif
8723 }
8724 
8725 static void
8726 pmap_demote_l2_abort(pmap_t pmap, vm_offset_t va, pt_entry_t *l2,
8727     struct rwlock **lockp)
8728 {
8729 	struct spglist free;
8730 
8731 	SLIST_INIT(&free);
8732 	(void)pmap_remove_l2(pmap, l2, va, pmap_load(pmap_l1(pmap, va)), true,
8733 	    &free, lockp);
8734 	vm_page_free_pages_toq(&free, true);
8735 }
8736 
8737 /*
8738  * Create an L3 table to map all addresses within an L2 mapping.
8739  */
8740 static pt_entry_t *
8741 pmap_demote_l2_locked(pmap_t pmap, pt_entry_t *l2, vm_offset_t va,
8742     struct rwlock **lockp)
8743 {
8744 	pt_entry_t *l3, newl3, oldl2;
8745 	char *tmpl2;
8746 	vm_paddr_t l3phys;
8747 	vm_page_t ml3;
8748 
8749 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
8750 	PMAP_ASSERT_STAGE1(pmap);
8751 	KASSERT(ADDR_IS_CANONICAL(va),
8752 	    ("%s: Address not in canonical form: %lx", __func__, va));
8753 
8754 	l3 = NULL;
8755 	oldl2 = pmap_load(l2);
8756 	KASSERT((oldl2 & ATTR_DESCR_MASK) == L2_BLOCK,
8757 	    ("pmap_demote_l2: Demoting a non-block entry"));
8758 	KASSERT((oldl2 & ATTR_SW_NO_PROMOTE) == 0,
8759 	    ("pmap_demote_l2: Demoting entry with no-demote flag set"));
8760 	va &= ~L2_OFFSET;
8761 
8762 	tmpl2 = NULL;
8763 	if (va <= (vm_offset_t)l2 && va + L2_SIZE > (vm_offset_t)l2) {
8764 		tmpl2 = kva_alloc(PAGE_SIZE);
8765 		if (tmpl2 == NULL)
8766 			return (NULL);
8767 	}
8768 
8769 	/*
8770 	 * Invalidate the 2MB page mapping and return "failure" if the
8771 	 * mapping was never accessed and not wired.
8772 	 */
8773 	if ((oldl2 & ATTR_AF) == 0) {
8774 		if ((oldl2 & ATTR_SW_WIRED) == 0) {
8775 			pmap_demote_l2_abort(pmap, va, l2, lockp);
8776 			CTR2(KTR_PMAP,
8777 			    "pmap_demote_l2: failure for va %#lx in pmap %p",
8778 			    va, pmap);
8779 			goto fail;
8780 		}
8781 		ml3 = pmap_remove_pt_page(pmap, va);
8782 		/* Fill the PTP with L3Es that have ATTR_AF cleared. */
8783 		ml3->valid = 0;
8784 	} else if ((ml3 = pmap_remove_pt_page(pmap, va)) == NULL) {
8785 		KASSERT((oldl2 & ATTR_SW_WIRED) == 0,
8786 		    ("pmap_demote_l2: page table page for a wired mapping"
8787 		    " is missing"));
8788 
8789 		/*
8790 		 * If the page table page is missing and the mapping
8791 		 * is for a kernel address, the mapping must belong to
8792 		 * either the direct map or the early kernel memory.
8793 		 * Page table pages are preallocated for every other
8794 		 * part of the kernel address space, so the direct map
8795 		 * region and early kernel memory are the only parts of the
8796 		 * kernel address space that must be handled here.
8797 		 */
8798 		KASSERT(ADDR_IS_USER(va) || VIRT_IN_DMAP(va) ||
8799 		    (va >= VM_MIN_KERNEL_ADDRESS && va < kernel_vm_end),
8800 		    ("pmap_demote_l2: No saved mpte for va %#lx", va));
8801 
8802 		/*
8803 		 * If the 2MB page mapping belongs to the direct map
8804 		 * region of the kernel's address space, then the page
8805 		 * allocation request specifies the highest possible
8806 		 * priority (VM_ALLOC_INTERRUPT).  Otherwise, the
8807 		 * priority is normal.
8808 		 */
8809 		ml3 = vm_page_alloc_noobj(
8810 		    (VIRT_IN_DMAP(va) ? VM_ALLOC_INTERRUPT : 0) |
8811 		    VM_ALLOC_WIRED);
8812 
8813 		/*
8814 		 * If the allocation of the new page table page fails,
8815 		 * invalidate the 2MB page mapping and return "failure".
8816 		 */
8817 		if (ml3 == NULL) {
8818 			pmap_demote_l2_abort(pmap, va, l2, lockp);
8819 			CTR2(KTR_PMAP, "pmap_demote_l2: failure for va %#lx"
8820 			    " in pmap %p", va, pmap);
8821 			goto fail;
8822 		}
8823 		ml3->pindex = pmap_l2_pindex(va);
8824 
8825 		if (ADDR_IS_USER(va)) {
8826 			ml3->ref_count = NL3PG;
8827 			pmap_resident_count_inc(pmap, 1);
8828 		}
8829 	}
8830 	l3phys = VM_PAGE_TO_PHYS(ml3);
8831 	l3 = PHYS_TO_DMAP(l3phys);
8832 	newl3 = ATTR_CONTIGUOUS | (oldl2 & ~ATTR_DESCR_MASK) | L3_PAGE;
8833 	KASSERT((oldl2 & (ATTR_S1_AP_RW_BIT | ATTR_SW_DBM)) !=
8834 	    (ATTR_S1_AP(ATTR_S1_AP_RO) | ATTR_SW_DBM),
8835 	    ("pmap_demote_l2: L2 entry is writeable but not dirty"));
8836 
8837 	/*
8838 	 * If the PTP is not leftover from an earlier promotion or it does not
8839 	 * have ATTR_AF set in every L3E, then fill it.  The new L3Es will all
8840 	 * have ATTR_AF set, unless this is a wired mapping with ATTR_AF clear.
8841 	 *
8842 	 * When pmap_update_entry() clears the old L2 mapping, it (indirectly)
8843 	 * performs a dsb().  That dsb() ensures that the stores for filling
8844 	 * "l3" are visible before "l3" is added to the page table.
8845 	 */
8846 	if (!vm_page_all_valid(ml3))
8847 		pmap_fill_l3(l3, newl3);
8848 
8849 	pmap_demote_l2_check(l3, newl3);
8850 
8851 	/*
8852 	 * If the mapping has changed attributes, update the L3Es.
8853 	 */
8854 	if ((pmap_load(l3) & ATTR_PROMOTE) != (newl3 & ATTR_PROMOTE))
8855 		pmap_fill_l3(l3, newl3);
8856 
8857 	/*
8858 	 * Map the temporary page so we don't lose access to the l2 table.
8859 	 */
8860 	if (tmpl2 != NULL) {
8861 		pmap_kenter((vm_offset_t)tmpl2, PAGE_SIZE,
8862 		    DMAP_TO_PHYS(l2) & ~L3_OFFSET,
8863 		    VM_MEMATTR_WRITE_BACK);
8864 		l2 = (pt_entry_t *)(tmpl2 + ((vm_offset_t)l2 & PAGE_MASK));
8865 	}
8866 
8867 	/*
8868 	 * The spare PV entries must be reserved prior to demoting the
8869 	 * mapping, that is, prior to changing the PDE.  Otherwise, the state
8870 	 * of the L2 and the PV lists will be inconsistent, which can result
8871 	 * in reclaim_pv_chunk() attempting to remove a PV entry from the
8872 	 * wrong PV list and pmap_pv_demote_l2() failing to find the expected
8873 	 * PV entry for the 2MB page mapping that is being demoted.
8874 	 */
8875 	if ((oldl2 & ATTR_SW_MANAGED) != 0)
8876 		reserve_pv_entries(pmap, Ln_ENTRIES - 1, lockp);
8877 
8878 	/*
8879 	 * Pass PAGE_SIZE so that a single TLB invalidation is performed on
8880 	 * the 2MB page mapping.
8881 	 */
8882 	pmap_update_entry(pmap, l2, l3phys | L2_TABLE, va, PAGE_SIZE);
8883 
8884 	/*
8885 	 * Demote the PV entry.
8886 	 */
8887 	if ((oldl2 & ATTR_SW_MANAGED) != 0)
8888 		pmap_pv_demote_l2(pmap, va, PTE_TO_PHYS(oldl2), lockp);
8889 
8890 	counter_u64_add(pmap_l2_demotions, 1);
8891 	CTR3(KTR_PMAP, "pmap_demote_l2: success for va %#lx"
8892 	    " in pmap %p %lx", va, pmap, l3[0]);
8893 
8894 fail:
8895 	if (tmpl2 != NULL) {
8896 		pmap_kremove((vm_offset_t)tmpl2);
8897 		kva_free(tmpl2, PAGE_SIZE);
8898 	}
8899 
8900 	return (l3);
8901 
8902 }
8903 
8904 static pt_entry_t *
8905 pmap_demote_l2(pmap_t pmap, pt_entry_t *l2, vm_offset_t va)
8906 {
8907 	struct rwlock *lock;
8908 	pt_entry_t *l3;
8909 
8910 	lock = NULL;
8911 	l3 = pmap_demote_l2_locked(pmap, l2, va, &lock);
8912 	if (lock != NULL)
8913 		rw_wunlock(lock);
8914 	return (l3);
8915 }
8916 
8917 /*
8918  * Demote an L2C superpage mapping to L2C_ENTRIES L2 block mappings.
8919  */
8920 static bool
8921 pmap_demote_l2c(pmap_t pmap, pt_entry_t *l2p, vm_offset_t va)
8922 {
8923 	pd_entry_t *l2c_end, *l2c_start, l2e, mask, nbits, *tl2p;
8924 	char *tmpl3;
8925 	register_t intr;
8926 
8927 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
8928 	PMAP_ASSERT_STAGE1(pmap);
8929 	l2c_start = (pd_entry_t *)((uintptr_t)l2p & ~((L2C_ENTRIES *
8930 	    sizeof(pd_entry_t)) - 1));
8931 	l2c_end = l2c_start + L2C_ENTRIES;
8932 	tmpl3 = NULL;
8933 	if ((va & ~L2C_OFFSET) < (vm_offset_t)l2c_end &&
8934 	    (vm_offset_t)l2c_start < (va & ~L2C_OFFSET) + L2C_SIZE) {
8935 		tmpl3 = kva_alloc(PAGE_SIZE);
8936 		if (tmpl3 == NULL)
8937 			return (false);
8938 		pmap_kenter((vm_offset_t)tmpl3, PAGE_SIZE,
8939 		    DMAP_TO_PHYS(l2c_start) & ~L3_OFFSET,
8940 		    VM_MEMATTR_WRITE_BACK);
8941 		l2c_start = (pd_entry_t *)(tmpl3 +
8942 		    ((vm_offset_t)l2c_start & PAGE_MASK));
8943 		l2c_end = (pd_entry_t *)(tmpl3 +
8944 		    ((vm_offset_t)l2c_end & PAGE_MASK));
8945 	}
8946 	mask = 0;
8947 	nbits = ATTR_DESCR_VALID;
8948 	intr = intr_disable();
8949 
8950 	/*
8951 	 * Break the mappings.
8952 	 */
8953 	for (tl2p = l2c_start; tl2p < l2c_end; tl2p++) {
8954 		/*
8955 		 * Clear the mapping's contiguous and valid bits, but leave
8956 		 * the rest of the entry unchanged, so that a lockless,
8957 		 * concurrent pmap_kextract() can still lookup the physical
8958 		 * address.
8959 		 */
8960 		l2e = pmap_load(tl2p);
8961 		KASSERT((l2e & ATTR_CONTIGUOUS) != 0,
8962 		    ("pmap_demote_l2c: missing ATTR_CONTIGUOUS"));
8963 		KASSERT((l2e & (ATTR_SW_DBM | ATTR_S1_AP_RW_BIT)) !=
8964 		    (ATTR_SW_DBM | ATTR_S1_AP(ATTR_S1_AP_RO)),
8965 		    ("pmap_demote_l2c: missing ATTR_S1_AP_RW"));
8966 		while (!atomic_fcmpset_64(tl2p, &l2e, l2e & ~(ATTR_CONTIGUOUS |
8967 		    ATTR_DESCR_VALID)))
8968 			cpu_spinwait();
8969 
8970 		/*
8971 		 * Hardware accessed and dirty bit maintenance might only
8972 		 * update a single L2 entry, so we must combine the accessed
8973 		 * and dirty bits from this entire set of contiguous L2
8974 		 * entries.
8975 		 */
8976 		if ((l2e & (ATTR_S1_AP_RW_BIT | ATTR_SW_DBM)) ==
8977 		    (ATTR_S1_AP(ATTR_S1_AP_RW) | ATTR_SW_DBM))
8978 			mask = ATTR_S1_AP_RW_BIT;
8979 		nbits |= l2e & ATTR_AF;
8980 	}
8981 	if ((nbits & ATTR_AF) != 0) {
8982 		pmap_s1_invalidate_strided(pmap, va & ~L2C_OFFSET, (va +
8983 		    L2C_SIZE) & ~L2C_OFFSET, L2_SIZE, true);
8984 	}
8985 
8986 	/*
8987 	 * Remake the mappings, updating the accessed and dirty bits.
8988 	 */
8989 	l2e = (pmap_load(l2c_start) & ~mask) | nbits;
8990 	for (tl2p = l2c_start; tl2p < l2c_end; tl2p++) {
8991 		pmap_store(tl2p, l2e);
8992 		l2e += L2_SIZE;
8993 	}
8994 	dsb(ishst);
8995 
8996 	intr_restore(intr);
8997 	if (tmpl3 != NULL) {
8998 		pmap_kremove((vm_offset_t)tmpl3);
8999 		kva_free(tmpl3, PAGE_SIZE);
9000 	}
9001 	counter_u64_add(pmap_l2c_demotions, 1);
9002 	CTR2(KTR_PMAP, "pmap_demote_l2c: success for va %#lx in pmap %p",
9003 	    va, pmap);
9004 	return (true);
9005 }
9006 
9007 /*
9008  * Demote a L3C superpage mapping to L3C_ENTRIES 4KB page mappings.
9009  */
9010 static bool
9011 pmap_demote_l3c(pmap_t pmap, pt_entry_t *l3p, vm_offset_t va)
9012 {
9013 	pt_entry_t *l3c_end, *l3c_start, l3e, mask, nbits, *tl3p;
9014 	char *tmpl3;
9015 	register_t intr;
9016 
9017 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
9018 	l3c_start = (pt_entry_t *)((uintptr_t)l3p & ~((L3C_ENTRIES *
9019 	    sizeof(pt_entry_t)) - 1));
9020 	l3c_end = l3c_start + L3C_ENTRIES;
9021 	tmpl3 = NULL;
9022 	if ((va & ~L3C_OFFSET) < (vm_offset_t)l3c_end &&
9023 	    (vm_offset_t)l3c_start < (va & ~L3C_OFFSET) + L3C_SIZE) {
9024 		tmpl3 = kva_alloc(PAGE_SIZE);
9025 		if (tmpl3 == NULL)
9026 			return (false);
9027 		pmap_kenter((vm_offset_t)tmpl3, PAGE_SIZE,
9028 		    DMAP_TO_PHYS(l3c_start) & ~L3_OFFSET,
9029 		    VM_MEMATTR_WRITE_BACK);
9030 		l3c_start = (pt_entry_t *)(tmpl3 +
9031 		    ((vm_offset_t)l3c_start & PAGE_MASK));
9032 		l3c_end = (pt_entry_t *)(tmpl3 +
9033 		    ((vm_offset_t)l3c_end & PAGE_MASK));
9034 	}
9035 	mask = 0;
9036 	nbits = ATTR_DESCR_VALID;
9037 	intr = intr_disable();
9038 
9039 	/*
9040 	 * Break the mappings.
9041 	 */
9042 	for (tl3p = l3c_start; tl3p < l3c_end; tl3p++) {
9043 		/*
9044 		 * Clear the mapping's contiguous and valid bits, but leave
9045 		 * the rest of the entry unchanged, so that a lockless,
9046 		 * concurrent pmap_kextract() can still lookup the physical
9047 		 * address.
9048 		 */
9049 		l3e = pmap_load(tl3p);
9050 		KASSERT((l3e & ATTR_CONTIGUOUS) != 0,
9051 		    ("pmap_demote_l3c: missing ATTR_CONTIGUOUS"));
9052 		KASSERT((l3e & (ATTR_SW_DBM | ATTR_S1_AP_RW_BIT)) !=
9053 		    (ATTR_SW_DBM | ATTR_S1_AP(ATTR_S1_AP_RO)),
9054 		    ("pmap_demote_l3c: missing ATTR_S1_AP_RW"));
9055 		while (!atomic_fcmpset_64(tl3p, &l3e, l3e & ~(ATTR_CONTIGUOUS |
9056 		    ATTR_DESCR_VALID)))
9057 			cpu_spinwait();
9058 
9059 		/*
9060 		 * Hardware accessed and dirty bit maintenance might only
9061 		 * update a single L3 entry, so we must combine the accessed
9062 		 * and dirty bits from this entire set of contiguous L3
9063 		 * entries.
9064 		 */
9065 		if ((l3e & (ATTR_S1_AP_RW_BIT | ATTR_SW_DBM)) ==
9066 		    (ATTR_S1_AP(ATTR_S1_AP_RW) | ATTR_SW_DBM))
9067 			mask = ATTR_S1_AP_RW_BIT;
9068 		nbits |= l3e & ATTR_AF;
9069 	}
9070 	if ((nbits & ATTR_AF) != 0) {
9071 		pmap_invalidate_range(pmap, va & ~L3C_OFFSET, (va + L3C_SIZE) &
9072 		    ~L3C_OFFSET, true);
9073 	}
9074 
9075 	/*
9076 	 * Remake the mappings, updating the accessed and dirty bits.
9077 	 */
9078 	l3e = (pmap_load(l3c_start) & ~mask) | nbits;
9079 	for (tl3p = l3c_start; tl3p < l3c_end; tl3p++) {
9080 		pmap_store(tl3p, l3e);
9081 		l3e += L3_SIZE;
9082 	}
9083 	dsb(ishst);
9084 
9085 	intr_restore(intr);
9086 	if (tmpl3 != NULL) {
9087 		pmap_kremove((vm_offset_t)tmpl3);
9088 		kva_free(tmpl3, PAGE_SIZE);
9089 	}
9090 	counter_u64_add(pmap_l3c_demotions, 1);
9091 	CTR2(KTR_PMAP, "pmap_demote_l3c: success for va %#lx in pmap %p",
9092 	    va, pmap);
9093 	return (true);
9094 }
9095 
9096 /*
9097  * Accumulate the accessed and dirty bits within a L3C superpage and
9098  * return the specified PTE with them applied correctly.
9099  */
9100 static pt_entry_t
9101 pmap_load_l3c(pt_entry_t *l3p)
9102 {
9103 	pt_entry_t *l3c_end, *l3c_start, l3e, mask, nbits, *tl3p;
9104 
9105 	l3c_start = (pt_entry_t *)((uintptr_t)l3p & ~((L3C_ENTRIES *
9106 	    sizeof(pt_entry_t)) - 1));
9107 	l3c_end = l3c_start + L3C_ENTRIES;
9108 	mask = 0;
9109 	nbits = 0;
9110 	/* Iterate over each mapping in the superpage. */
9111 	for (tl3p = l3c_start; tl3p < l3c_end; tl3p++) {
9112 		l3e = pmap_load(tl3p);
9113 		KASSERT((l3e & ATTR_CONTIGUOUS) != 0,
9114 		    ("pmap_load_l3c: missing ATTR_CONTIGUOUS"));
9115 		/* Update mask if the current page has its dirty bit set. */
9116 		if ((l3e & (ATTR_S1_AP_RW_BIT | ATTR_SW_DBM)) ==
9117 		    (ATTR_S1_AP(ATTR_S1_AP_RW) | ATTR_SW_DBM))
9118 			mask = ATTR_S1_AP_RW_BIT;
9119 		/* Update nbits if the accessed bit is set. */
9120 		nbits |= l3e & ATTR_AF;
9121 	}
9122 	return ((pmap_load(l3p) & ~mask) | nbits);
9123 }
9124 
9125 /*
9126  * Perform the pmap work for mincore(2).  If the page is not both referenced and
9127  * modified by this pmap, returns its physical address so that the caller can
9128  * find other mappings.
9129  */
9130 int
9131 pmap_mincore(pmap_t pmap, vm_offset_t addr, vm_paddr_t *pap)
9132 {
9133 	pt_entry_t *pte, tpte;
9134 	vm_paddr_t mask, pa;
9135 	int lvl, psind, val;
9136 	bool managed;
9137 
9138 	PMAP_ASSERT_STAGE1(pmap);
9139 	PMAP_LOCK(pmap);
9140 	pte = pmap_pte(pmap, addr, &lvl);
9141 	if (pte != NULL) {
9142 		tpte = pmap_load(pte);
9143 
9144 		switch (lvl) {
9145 		case 3:
9146 			mask = L3_OFFSET;
9147 			psind = (tpte & ATTR_CONTIGUOUS) != 0 ? 1 : 0;
9148 			break;
9149 		case 2:
9150 			mask = L2_OFFSET;
9151 			psind = 2;
9152 			break;
9153 		case 1:
9154 			mask = L1_OFFSET;
9155 			psind = 3;
9156 			break;
9157 		default:
9158 			panic("pmap_mincore: invalid level %d", lvl);
9159 		}
9160 
9161 		managed = (tpte & ATTR_SW_MANAGED) != 0;
9162 		val = MINCORE_INCORE | MINCORE_PSIND(psind);
9163 		if ((managed && pmap_pte_dirty(pmap, tpte)) || (!managed &&
9164 		    (tpte & ATTR_S1_AP_RW_BIT) == ATTR_S1_AP(ATTR_S1_AP_RW)))
9165 			val |= MINCORE_MODIFIED | MINCORE_MODIFIED_OTHER;
9166 		if ((tpte & ATTR_AF) == ATTR_AF)
9167 			val |= MINCORE_REFERENCED | MINCORE_REFERENCED_OTHER;
9168 
9169 		pa = PTE_TO_PHYS(tpte) | (addr & mask);
9170 	} else {
9171 		managed = false;
9172 		val = 0;
9173 	}
9174 
9175 	if ((val & (MINCORE_MODIFIED_OTHER | MINCORE_REFERENCED_OTHER)) !=
9176 	    (MINCORE_MODIFIED_OTHER | MINCORE_REFERENCED_OTHER) && managed) {
9177 		*pap = pa;
9178 	}
9179 	PMAP_UNLOCK(pmap);
9180 	return (val);
9181 }
9182 
9183 /*
9184  * Garbage collect every ASID that is neither active on a processor nor
9185  * reserved.
9186  */
9187 static void
9188 pmap_reset_asid_set(pmap_t pmap)
9189 {
9190 	pmap_t curpmap;
9191 	int asid, cpuid, epoch;
9192 	struct asid_set *set;
9193 	enum pmap_stage stage;
9194 
9195 	set = pmap->pm_asid_set;
9196 	stage = pmap->pm_stage;
9197 
9198 	set = pmap->pm_asid_set;
9199 	KASSERT(set != NULL, ("%s: NULL asid set", __func__));
9200 	mtx_assert(&set->asid_set_mutex, MA_OWNED);
9201 
9202 	/*
9203 	 * Ensure that the store to asid_epoch is globally visible before the
9204 	 * loads from pc_curpmap are performed.
9205 	 */
9206 	epoch = set->asid_epoch + 1;
9207 	if (epoch == INT_MAX)
9208 		epoch = 0;
9209 	set->asid_epoch = epoch;
9210 	dsb(ishst);
9211 	if (stage == PM_STAGE1) {
9212 		__asm __volatile("tlbi vmalle1is");
9213 	} else {
9214 		KASSERT(pmap_clean_stage2_tlbi != NULL,
9215 		    ("%s: Unset stage 2 tlb invalidation callback\n",
9216 		    __func__));
9217 		pmap_clean_stage2_tlbi();
9218 	}
9219 	dsb(ish);
9220 	bit_nclear(set->asid_set, ASID_FIRST_AVAILABLE,
9221 	    set->asid_set_size - 1);
9222 	CPU_FOREACH(cpuid) {
9223 		if (cpuid == curcpu)
9224 			continue;
9225 		if (stage == PM_STAGE1) {
9226 			curpmap = pcpu_find(cpuid)->pc_curpmap;
9227 			PMAP_ASSERT_STAGE1(pmap);
9228 		} else {
9229 			curpmap = pcpu_find(cpuid)->pc_curvmpmap;
9230 			if (curpmap == NULL)
9231 				continue;
9232 			PMAP_ASSERT_STAGE2(pmap);
9233 		}
9234 		KASSERT(curpmap->pm_asid_set == set, ("Incorrect set"));
9235 		asid = COOKIE_TO_ASID(curpmap->pm_cookie);
9236 		if (asid == -1)
9237 			continue;
9238 		bit_set(set->asid_set, asid);
9239 		curpmap->pm_cookie = COOKIE_FROM(asid, epoch);
9240 	}
9241 }
9242 
9243 /*
9244  * Allocate a new ASID for the specified pmap.
9245  */
9246 static void
9247 pmap_alloc_asid(pmap_t pmap)
9248 {
9249 	struct asid_set *set;
9250 	int new_asid;
9251 
9252 	set = pmap->pm_asid_set;
9253 	KASSERT(set != NULL, ("%s: NULL asid set", __func__));
9254 
9255 	mtx_lock_spin(&set->asid_set_mutex);
9256 
9257 	/*
9258 	 * While this processor was waiting to acquire the asid set mutex,
9259 	 * pmap_reset_asid_set() running on another processor might have
9260 	 * updated this pmap's cookie to the current epoch.  In which case, we
9261 	 * don't need to allocate a new ASID.
9262 	 */
9263 	if (COOKIE_TO_EPOCH(pmap->pm_cookie) == set->asid_epoch)
9264 		goto out;
9265 
9266 	bit_ffc_at(set->asid_set, set->asid_next, set->asid_set_size,
9267 	    &new_asid);
9268 	if (new_asid == -1) {
9269 		bit_ffc_at(set->asid_set, ASID_FIRST_AVAILABLE,
9270 		    set->asid_next, &new_asid);
9271 		if (new_asid == -1) {
9272 			pmap_reset_asid_set(pmap);
9273 			bit_ffc_at(set->asid_set, ASID_FIRST_AVAILABLE,
9274 			    set->asid_set_size, &new_asid);
9275 			KASSERT(new_asid != -1, ("ASID allocation failure"));
9276 		}
9277 	}
9278 	bit_set(set->asid_set, new_asid);
9279 	set->asid_next = new_asid + 1;
9280 	pmap->pm_cookie = COOKIE_FROM(new_asid, set->asid_epoch);
9281 out:
9282 	mtx_unlock_spin(&set->asid_set_mutex);
9283 }
9284 
9285 static uint64_t __read_mostly ttbr_flags;
9286 
9287 /*
9288  * Compute the value that should be stored in ttbr0 to activate the specified
9289  * pmap.  This value may change from time to time.
9290  */
9291 uint64_t
9292 pmap_to_ttbr0(pmap_t pmap)
9293 {
9294 	uint64_t ttbr;
9295 
9296 	ttbr = pmap->pm_ttbr;
9297 	ttbr |= ASID_TO_OPERAND(COOKIE_TO_ASID(pmap->pm_cookie));
9298 	ttbr |= ttbr_flags;
9299 
9300 	return (ttbr);
9301 }
9302 
9303 static void
9304 pmap_set_cnp(void *arg)
9305 {
9306 	uint64_t ttbr0, ttbr1;
9307 	u_int cpuid;
9308 
9309 	cpuid = *(u_int *)arg;
9310 	if (cpuid == curcpu) {
9311 		/*
9312 		 * Set the flags while all CPUs are handling the
9313 		 * smp_rendezvous so will not call pmap_to_ttbr0. Any calls
9314 		 * to pmap_to_ttbr0 after this will have the CnP flag set.
9315 		 * The dsb after invalidating the TLB will act as a barrier
9316 		 * to ensure all CPUs can observe this change.
9317 		 */
9318 		ttbr_flags |= TTBR_CnP;
9319 	}
9320 
9321 	ttbr0 = READ_SPECIALREG(ttbr0_el1);
9322 	ttbr0 |= TTBR_CnP;
9323 
9324 	ttbr1 = READ_SPECIALREG(ttbr1_el1);
9325 	ttbr1 |= TTBR_CnP;
9326 
9327 	/* Update ttbr{0,1}_el1 with the CnP flag */
9328 	WRITE_SPECIALREG(ttbr0_el1, ttbr0);
9329 	WRITE_SPECIALREG(ttbr1_el1, ttbr1);
9330 	isb();
9331 	__asm __volatile("tlbi vmalle1is");
9332 	dsb(ish);
9333 	isb();
9334 }
9335 
9336 /*
9337  * Defer enabling some features until we have read the ID registers to know
9338  * if they are supported on all CPUs.
9339  */
9340 static void
9341 pmap_init_mp(void *dummy __unused)
9342 {
9343 	uint64_t reg;
9344 
9345 	get_kernel_reg(ID_AA64PFR1_EL1, &reg);
9346 	if (ID_AA64PFR1_BT_VAL(reg) != ID_AA64PFR1_BT_NONE) {
9347 		if (bootverbose)
9348 			printf("Enabling BTI\n");
9349 		pmap_bti_support = true;
9350 
9351 		pmap_bti_ranges_zone = uma_zcreate("BTI ranges",
9352 		    sizeof(struct rs_el), NULL, NULL, NULL, NULL,
9353 		    UMA_ALIGN_PTR, 0);
9354 	}
9355 }
9356 SYSINIT(pmap_init_mp, SI_SUB_CPU, SI_ORDER_ANY, pmap_init_mp, NULL);
9357 
9358 /*
9359  * Defer enabling CnP until we have read the ID registers to know if it's
9360  * supported on all CPUs.
9361  */
9362 static void
9363 pmap_init_cnp(void *dummy __unused)
9364 {
9365 	uint64_t reg;
9366 	u_int cpuid;
9367 
9368 	get_kernel_reg(ID_AA64MMFR2_EL1, &reg);
9369 	if (ID_AA64MMFR2_CnP_VAL(reg) != ID_AA64MMFR2_CnP_NONE) {
9370 		if (bootverbose)
9371 			printf("Enabling CnP\n");
9372 		cpuid = curcpu;
9373 		smp_rendezvous(NULL, pmap_set_cnp, NULL, &cpuid);
9374 	}
9375 
9376 }
9377 SYSINIT(pmap_init_cnp, SI_SUB_SMP, SI_ORDER_ANY, pmap_init_cnp, NULL);
9378 
9379 static bool
9380 pmap_activate_int(struct thread *td, pmap_t pmap)
9381 {
9382 	struct asid_set *set;
9383 	int epoch;
9384 
9385 	KASSERT(PCPU_GET(curpmap) != NULL, ("no active pmap"));
9386 	KASSERT(pmap != kernel_pmap, ("kernel pmap activation"));
9387 
9388 	if ((pmap->pm_stage == PM_STAGE1 && pmap == PCPU_GET(curpmap)) ||
9389 	    (pmap->pm_stage == PM_STAGE2 && pmap == PCPU_GET(curvmpmap))) {
9390 		/*
9391 		 * Handle the possibility that the old thread was preempted
9392 		 * after an "ic" or "tlbi" instruction but before it performed
9393 		 * a "dsb" instruction.  If the old thread migrates to a new
9394 		 * processor, its completion of a "dsb" instruction on that
9395 		 * new processor does not guarantee that the "ic" or "tlbi"
9396 		 * instructions performed on the old processor have completed.
9397 		 */
9398 		dsb(ish);
9399 		return (false);
9400 	}
9401 
9402 	set = pmap->pm_asid_set;
9403 	KASSERT(set != NULL, ("%s: NULL asid set", __func__));
9404 
9405 	/*
9406 	 * Ensure that the store to curpmap is globally visible before the
9407 	 * load from asid_epoch is performed.
9408 	 */
9409 	if (pmap->pm_stage == PM_STAGE1)
9410 		PCPU_SET(curpmap, pmap);
9411 	else
9412 		PCPU_SET(curvmpmap, pmap);
9413 	dsb(ish);
9414 	epoch = COOKIE_TO_EPOCH(pmap->pm_cookie);
9415 	if (epoch >= 0 && epoch != set->asid_epoch)
9416 		pmap_alloc_asid(pmap);
9417 
9418 	if (pmap->pm_stage == PM_STAGE1) {
9419 		uint64_t new_tcr, tcr;
9420 
9421 		new_tcr = td->td_proc->p_md.md_tcr;
9422 		tcr = READ_SPECIALREG(tcr_el1);
9423 		if ((tcr & MD_TCR_FIELDS) != new_tcr) {
9424 			tcr &= ~MD_TCR_FIELDS;
9425 			tcr |= new_tcr;
9426 			WRITE_SPECIALREG(tcr_el1, tcr);
9427 		}
9428 		set_ttbr0(pmap_to_ttbr0(pmap));
9429 		if (PCPU_GET(bcast_tlbi_workaround) != 0)
9430 			invalidate_local_icache();
9431 	}
9432 	return (true);
9433 }
9434 
9435 void
9436 pmap_activate_vm(pmap_t pmap)
9437 {
9438 
9439 	PMAP_ASSERT_STAGE2(pmap);
9440 
9441 	(void)pmap_activate_int(NULL, pmap);
9442 }
9443 
9444 void
9445 pmap_activate(struct thread *td)
9446 {
9447 	pmap_t	pmap;
9448 
9449 	pmap = vmspace_pmap(td->td_proc->p_vmspace);
9450 	PMAP_ASSERT_STAGE1(pmap);
9451 	critical_enter();
9452 	(void)pmap_activate_int(td, pmap);
9453 	critical_exit();
9454 }
9455 
9456 /*
9457  * Activate the thread we are switching to.
9458  * To simplify the assembly in cpu_throw return the new threads pcb.
9459  */
9460 struct pcb *
9461 pmap_switch(struct thread *new)
9462 {
9463 	pcpu_bp_harden bp_harden;
9464 	struct pcb *pcb;
9465 	uint64_t sctlr;
9466 
9467 	/* Store the new curthread */
9468 	PCPU_SET(curthread, new);
9469 
9470 	/* And the new pcb */
9471 	pcb = new->td_pcb;
9472 	PCPU_SET(curpcb, pcb);
9473 
9474 	if ((new->td_proc->p_flag & P_KPROC) == 0) {
9475 		sctlr = READ_SPECIALREG(sctlr_el1);
9476 		if ((sctlr & SCTLR_USER_MASK) != new->td_md.md_sctlr) {
9477 			sctlr &= ~SCTLR_USER_MASK;
9478 			sctlr |= new->td_md.md_sctlr;
9479 			WRITE_SPECIALREG(sctlr_el1, sctlr);
9480 			isb();
9481 		}
9482 	}
9483 
9484 	/*
9485 	 * TODO: We may need to flush the cache here if switching
9486 	 * to a user process.
9487 	 */
9488 
9489 	if (pmap_activate_int(new, vmspace_pmap(new->td_proc->p_vmspace))) {
9490 		/*
9491 		 * Stop userspace from training the branch predictor against
9492 		 * other processes. This will call into a CPU specific
9493 		 * function that clears the branch predictor state.
9494 		 */
9495 		bp_harden = PCPU_GET(bp_harden);
9496 		if (bp_harden != NULL)
9497 			bp_harden();
9498 	}
9499 
9500 	return (pcb);
9501 }
9502 
9503 void
9504 pmap_sync_icache(pmap_t pmap, vm_offset_t va, vm_size_t sz)
9505 {
9506 
9507 	PMAP_ASSERT_STAGE1(pmap);
9508 	KASSERT(ADDR_IS_CANONICAL(va),
9509 	    ("%s: Address not in canonical form: %lx", __func__, va));
9510 
9511 	if (ADDR_IS_KERNEL(va)) {
9512 		cpu_icache_sync_range((void *)va, sz);
9513 	} else {
9514 		u_int len, offset;
9515 		vm_paddr_t pa;
9516 
9517 		/* Find the length of data in this page to flush */
9518 		offset = va & PAGE_MASK;
9519 		len = imin(PAGE_SIZE - offset, sz);
9520 
9521 		while (sz != 0) {
9522 			/* Extract the physical address & find it in the DMAP */
9523 			pa = pmap_extract(pmap, va);
9524 			if (pa != 0)
9525 				cpu_icache_sync_range(PHYS_TO_DMAP(pa), len);
9526 
9527 			/* Move to the next page */
9528 			sz -= len;
9529 			va += len;
9530 			/* Set the length for the next iteration */
9531 			len = imin(PAGE_SIZE, sz);
9532 		}
9533 	}
9534 }
9535 
9536 static int
9537 pmap_stage2_fault(pmap_t pmap, uint64_t esr, uint64_t far)
9538 {
9539 	pd_entry_t *pdep;
9540 	pt_entry_t *ptep, pte;
9541 	int rv, lvl, dfsc;
9542 
9543 	PMAP_ASSERT_STAGE2(pmap);
9544 	rv = KERN_FAILURE;
9545 
9546 	/* Data and insn aborts use same encoding for FSC field. */
9547 	dfsc = esr & ISS_DATA_DFSC_MASK;
9548 	switch (dfsc) {
9549 	case ISS_DATA_DFSC_TF_L0:
9550 	case ISS_DATA_DFSC_TF_L1:
9551 	case ISS_DATA_DFSC_TF_L2:
9552 	case ISS_DATA_DFSC_TF_L3:
9553 		PMAP_LOCK(pmap);
9554 		pdep = pmap_pde(pmap, far, &lvl);
9555 		if (pdep == NULL || lvl != (dfsc - ISS_DATA_DFSC_TF_L1)) {
9556 			PMAP_UNLOCK(pmap);
9557 			break;
9558 		}
9559 
9560 		switch (lvl) {
9561 		case 0:
9562 			ptep = pmap_l0_to_l1(pdep, far);
9563 			break;
9564 		case 1:
9565 			ptep = pmap_l1_to_l2(pdep, far);
9566 			break;
9567 		case 2:
9568 			ptep = pmap_l2_to_l3(pdep, far);
9569 			break;
9570 		default:
9571 			panic("%s: Invalid pde level %d", __func__,lvl);
9572 		}
9573 		goto fault_exec;
9574 
9575 	case ISS_DATA_DFSC_AFF_L1:
9576 	case ISS_DATA_DFSC_AFF_L2:
9577 	case ISS_DATA_DFSC_AFF_L3:
9578 		PMAP_LOCK(pmap);
9579 		ptep = pmap_pte(pmap, far, &lvl);
9580 fault_exec:
9581 		if (ptep != NULL && (pte = pmap_load(ptep)) != 0) {
9582 			/*
9583 			 * If accessing an executable page invalidate
9584 			 * the I-cache so it will be valid when we
9585 			 * continue execution in the guest. The D-cache
9586 			 * is assumed to already be clean to the Point
9587 			 * of Coherency.
9588 			 */
9589 			if ((pte & ATTR_S2_XN_MASK) !=
9590 			    ATTR_S2_XN(ATTR_S2_XN_NONE)) {
9591 				invalidate_icache();
9592 			}
9593 			pmap_set_bits(ptep, ATTR_AF | ATTR_DESCR_VALID);
9594 			rv = KERN_SUCCESS;
9595 		}
9596 		PMAP_UNLOCK(pmap);
9597 		break;
9598 	}
9599 
9600 	return (rv);
9601 }
9602 
9603 int
9604 pmap_fault(pmap_t pmap, uint64_t esr, uint64_t far)
9605 {
9606 	pt_entry_t pte, *ptep;
9607 	register_t intr;
9608 	uint64_t ec, par;
9609 	int lvl, rv;
9610 
9611 	rv = KERN_FAILURE;
9612 
9613 	ec = ESR_ELx_EXCEPTION(esr);
9614 	switch (ec) {
9615 	case EXCP_INSN_ABORT_L:
9616 	case EXCP_INSN_ABORT:
9617 	case EXCP_DATA_ABORT_L:
9618 	case EXCP_DATA_ABORT:
9619 		break;
9620 	default:
9621 		return (rv);
9622 	}
9623 
9624 	if (pmap->pm_stage == PM_STAGE2)
9625 		return (pmap_stage2_fault(pmap, esr, far));
9626 
9627 	/* Data and insn aborts use same encoding for FSC field. */
9628 	switch (esr & ISS_DATA_DFSC_MASK) {
9629 	case ISS_DATA_DFSC_AFF_L1:
9630 	case ISS_DATA_DFSC_AFF_L2:
9631 	case ISS_DATA_DFSC_AFF_L3:
9632 		PMAP_LOCK(pmap);
9633 		ptep = pmap_pte(pmap, far, &lvl);
9634 		if (ptep != NULL) {
9635 			pmap_set_bits(ptep, ATTR_AF);
9636 			rv = KERN_SUCCESS;
9637 			/*
9638 			 * XXXMJ as an optimization we could mark the entry
9639 			 * dirty if this is a write fault.
9640 			 */
9641 		}
9642 		PMAP_UNLOCK(pmap);
9643 		break;
9644 	case ISS_DATA_DFSC_PF_L1:
9645 	case ISS_DATA_DFSC_PF_L2:
9646 	case ISS_DATA_DFSC_PF_L3:
9647 		if ((ec != EXCP_DATA_ABORT_L && ec != EXCP_DATA_ABORT) ||
9648 		    (esr & ISS_DATA_WnR) == 0)
9649 			return (rv);
9650 		PMAP_LOCK(pmap);
9651 		ptep = pmap_pte(pmap, far, &lvl);
9652 		if (ptep != NULL &&
9653 		    ((pte = pmap_load(ptep)) & ATTR_SW_DBM) != 0) {
9654 			if ((pte & ATTR_S1_AP_RW_BIT) ==
9655 			    ATTR_S1_AP(ATTR_S1_AP_RO)) {
9656 				pmap_clear_bits(ptep, ATTR_S1_AP_RW_BIT);
9657 				pmap_s1_invalidate_page(pmap, far, true);
9658 			}
9659 			rv = KERN_SUCCESS;
9660 		}
9661 		PMAP_UNLOCK(pmap);
9662 		break;
9663 	case ISS_DATA_DFSC_TF_L0:
9664 	case ISS_DATA_DFSC_TF_L1:
9665 	case ISS_DATA_DFSC_TF_L2:
9666 	case ISS_DATA_DFSC_TF_L3:
9667 		/*
9668 		 * Retry the translation.  A break-before-make sequence can
9669 		 * produce a transient fault.
9670 		 */
9671 		if (pmap == kernel_pmap) {
9672 			/*
9673 			 * The translation fault may have occurred within a
9674 			 * critical section.  Therefore, we must check the
9675 			 * address without acquiring the kernel pmap's lock.
9676 			 */
9677 			if (pmap_klookup(far, NULL))
9678 				rv = KERN_SUCCESS;
9679 		} else {
9680 			bool owned;
9681 
9682 			/*
9683 			 * In the EFIRT driver we lock the pmap before
9684 			 * calling into the runtime service. As the lock
9685 			 * is already owned by the current thread skip
9686 			 * locking it again.
9687 			 */
9688 			owned = PMAP_OWNED(pmap);
9689 			if (!owned)
9690 				PMAP_LOCK(pmap);
9691 			/* Ask the MMU to check the address. */
9692 			intr = intr_disable();
9693 			par = arm64_address_translate_s1e0r(far);
9694 			intr_restore(intr);
9695 			if (!owned)
9696 				PMAP_UNLOCK(pmap);
9697 
9698 			/*
9699 			 * If the translation was successful, then we can
9700 			 * return success to the trap handler.
9701 			 */
9702 			if (PAR_SUCCESS(par))
9703 				rv = KERN_SUCCESS;
9704 		}
9705 		break;
9706 	}
9707 
9708 	return (rv);
9709 }
9710 
9711 /*
9712  *	Increase the starting virtual address of the given mapping if a
9713  *	different alignment might result in more superpage mappings.
9714  */
9715 void
9716 pmap_align_superpage(vm_object_t object, vm_ooffset_t offset,
9717     vm_offset_t *addr, vm_size_t size)
9718 {
9719 	vm_offset_t superpage_offset;
9720 
9721 	if (size < L3C_SIZE)
9722 		return;
9723 	if (object != NULL && (object->flags & OBJ_COLORED) != 0)
9724 		offset += ptoa(object->pg_color);
9725 
9726 	/*
9727 	 * Considering the object's physical alignment, is the mapping large
9728 	 * enough to encompass an L2 (2MB/32MB) superpage ...
9729 	 */
9730 	superpage_offset = offset & L2_OFFSET;
9731 	if (size - ((L2_SIZE - superpage_offset) & L2_OFFSET) >= L2_SIZE) {
9732 		/*
9733 		 * If the virtual and physical alignments differ, then
9734 		 * increase the virtual address so that the alignments match.
9735 		 */
9736 		if ((*addr & L2_OFFSET) < superpage_offset)
9737 			*addr = (*addr & ~L2_OFFSET) + superpage_offset;
9738 		else if ((*addr & L2_OFFSET) > superpage_offset)
9739 			*addr = ((*addr + L2_OFFSET) & ~L2_OFFSET) +
9740 			    superpage_offset;
9741 		return;
9742 	}
9743 	/* ... or an L3C (64KB/2MB) superpage? */
9744 	superpage_offset = offset & L3C_OFFSET;
9745 	if (size - ((L3C_SIZE - superpage_offset) & L3C_OFFSET) >= L3C_SIZE) {
9746 		if ((*addr & L3C_OFFSET) < superpage_offset)
9747 			*addr = (*addr & ~L3C_OFFSET) + superpage_offset;
9748 		else if ((*addr & L3C_OFFSET) > superpage_offset)
9749 			*addr = ((*addr + L3C_OFFSET) & ~L3C_OFFSET) +
9750 			    superpage_offset;
9751 	}
9752 }
9753 
9754 /**
9755  * Get the kernel virtual address of a set of physical pages. If there are
9756  * physical addresses not covered by the DMAP perform a transient mapping
9757  * that will be removed when calling pmap_unmap_io_transient.
9758  *
9759  * \param page        The pages the caller wishes to obtain the virtual
9760  *                    address on the kernel memory map.
9761  * \param vaddr       On return contains the kernel virtual memory address
9762  *                    of the pages passed in the page parameter.
9763  * \param count       Number of pages passed in.
9764  * \param can_fault   true if the thread using the mapped pages can take
9765  *                    page faults, false otherwise.
9766  *
9767  * \returns true if the caller must call pmap_unmap_io_transient when
9768  *          finished or false otherwise.
9769  *
9770  */
9771 bool
9772 pmap_map_io_transient(vm_page_t page[], void *vaddr[], int count,
9773     bool can_fault)
9774 {
9775 	vm_paddr_t paddr;
9776 	vmem_addr_t addr;
9777 	bool needs_mapping;
9778 	int error __diagused, i;
9779 
9780 	/*
9781 	 * Allocate any KVA space that we need, this is done in a separate
9782 	 * loop to prevent calling vmem_alloc while pinned.
9783 	 */
9784 	needs_mapping = false;
9785 	for (i = 0; i < count; i++) {
9786 		paddr = VM_PAGE_TO_PHYS(page[i]);
9787 		if (__predict_false(!PHYS_IN_DMAP(paddr))) {
9788 			error = vmem_alloc(kernel_arena, PAGE_SIZE,
9789 			    M_BESTFIT | M_WAITOK, &addr);
9790 			KASSERT(error == 0, ("vmem_alloc failed: %d", error));
9791 			vaddr[i] = (void *)addr;
9792 			needs_mapping = true;
9793 		} else {
9794 			vaddr[i] = PHYS_TO_DMAP(paddr);
9795 		}
9796 	}
9797 
9798 	/* Exit early if everything is covered by the DMAP */
9799 	if (!needs_mapping)
9800 		return (false);
9801 
9802 	if (!can_fault)
9803 		sched_pin();
9804 	for (i = 0; i < count; i++) {
9805 		paddr = VM_PAGE_TO_PHYS(page[i]);
9806 		if (!PHYS_IN_DMAP(paddr)) {
9807 			panic(
9808 			   "pmap_map_io_transient: TODO: Map out of DMAP data");
9809 		}
9810 	}
9811 
9812 	return (needs_mapping);
9813 }
9814 
9815 void
9816 pmap_unmap_io_transient(vm_page_t page[], void *vaddr[], int count,
9817     bool can_fault)
9818 {
9819 	vm_paddr_t paddr;
9820 	int i;
9821 
9822 	if (!can_fault)
9823 		sched_unpin();
9824 	for (i = 0; i < count; i++) {
9825 		paddr = VM_PAGE_TO_PHYS(page[i]);
9826 		if (!PHYS_IN_DMAP(paddr)) {
9827 			panic("ARM64TODO: pmap_unmap_io_transient: Unmap data");
9828 		}
9829 	}
9830 }
9831 
9832 bool
9833 pmap_is_valid_memattr(pmap_t pmap __unused, vm_memattr_t mode)
9834 {
9835 
9836 	return (mode >= 0 && mode < VM_MEMATTR_END);
9837 }
9838 
9839 static void *
9840 bti_dup_range(void *ctx __unused, void *data)
9841 {
9842 	struct rs_el *node, *new_node;
9843 
9844 	new_node = uma_zalloc(pmap_bti_ranges_zone, M_NOWAIT);
9845 	if (new_node == NULL)
9846 		return (NULL);
9847 	node = data;
9848 	memcpy(new_node, node, sizeof(*node));
9849 	return (new_node);
9850 }
9851 
9852 static void
9853 bti_free_range(void *ctx __unused, void *node)
9854 {
9855 
9856 	uma_zfree(pmap_bti_ranges_zone, node);
9857 }
9858 
9859 static int
9860 pmap_bti_assign(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
9861 {
9862 	struct rs_el *rs;
9863 	int error;
9864 
9865 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
9866 	PMAP_ASSERT_STAGE1(pmap);
9867 	MPASS(pmap->pm_bti != NULL);
9868 	rs = uma_zalloc(pmap_bti_ranges_zone, M_NOWAIT);
9869 	if (rs == NULL)
9870 		return (ENOMEM);
9871 	error = rangeset_insert(pmap->pm_bti, sva, eva, rs);
9872 	if (error != 0)
9873 		uma_zfree(pmap_bti_ranges_zone, rs);
9874 	return (error);
9875 }
9876 
9877 static void
9878 pmap_bti_deassign_all(pmap_t pmap)
9879 {
9880 
9881 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
9882 	if (pmap->pm_bti != NULL)
9883 		rangeset_remove_all(pmap->pm_bti);
9884 }
9885 
9886 /*
9887  * Returns true if the BTI setting is the same across the specified address
9888  * range, and false otherwise.  When returning true, updates the referenced PTE
9889  * to reflect the BTI setting.
9890  *
9891  * Only stage 1 pmaps support BTI.  The kernel pmap is always a stage 1 pmap
9892  * that has the same BTI setting implicitly across its entire address range.
9893  */
9894 static bool
9895 pmap_bti_same(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, pt_entry_t *pte)
9896 {
9897 	struct rs_el *rs;
9898 	vm_offset_t va;
9899 
9900 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
9901 	KASSERT(ADDR_IS_CANONICAL(sva),
9902 	    ("%s: Start address not in canonical form: %lx", __func__, sva));
9903 	KASSERT(ADDR_IS_CANONICAL(eva),
9904 	    ("%s: End address not in canonical form: %lx", __func__, eva));
9905 	KASSERT((*pte & ATTR_S1_GP) == 0,
9906 	    ("%s: pte %lx has ATTR_S1_GP preset", __func__, *pte));
9907 
9908 	if (pmap == kernel_pmap) {
9909 		*pte |= ATTR_KERN_GP;
9910 		return (true);
9911 	}
9912 	if (pmap->pm_bti == NULL)
9913 		return (true);
9914 	PMAP_ASSERT_STAGE1(pmap);
9915 	rs = rangeset_containing(pmap->pm_bti, sva);
9916 	if (rs == NULL)
9917 		return (rangeset_empty(pmap->pm_bti, sva, eva));
9918 	while ((va = rs->re_end) < eva) {
9919 		if ((rs = rangeset_beginning(pmap->pm_bti, va)) == NULL)
9920 			return (false);
9921 	}
9922 	*pte |= ATTR_S1_GP;
9923 	return (true);
9924 }
9925 
9926 static pt_entry_t
9927 pmap_pte_bti(pmap_t pmap, vm_offset_t va)
9928 {
9929 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
9930 	MPASS(ADDR_IS_CANONICAL(va));
9931 
9932 	if (pmap->pm_stage != PM_STAGE1)
9933 		return (0);
9934 	if (pmap == kernel_pmap)
9935 		return (ATTR_KERN_GP);
9936 	if (pmap->pm_bti != NULL &&
9937 	    rangeset_containing(pmap->pm_bti, va) != NULL)
9938 		return (ATTR_S1_GP);
9939 	return (0);
9940 }
9941 
9942 static void
9943 pmap_bti_on_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
9944 {
9945 
9946 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
9947 	if (pmap->pm_bti != NULL)
9948 		rangeset_remove(pmap->pm_bti, sva, eva);
9949 }
9950 
9951 static int
9952 pmap_bti_copy(pmap_t dst_pmap, pmap_t src_pmap)
9953 {
9954 
9955 	PMAP_LOCK_ASSERT(dst_pmap, MA_OWNED);
9956 	PMAP_LOCK_ASSERT(src_pmap, MA_OWNED);
9957 	MPASS(src_pmap->pm_stage == dst_pmap->pm_stage);
9958 	MPASS(src_pmap->pm_bti != NULL);
9959 	MPASS(dst_pmap->pm_bti != NULL);
9960 	if (src_pmap->pm_bti->rs_data_ctx == NULL)
9961 		return (0);
9962 	return (rangeset_copy(dst_pmap->pm_bti, src_pmap->pm_bti));
9963 }
9964 
9965 static void
9966 pmap_bti_update_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, bool set)
9967 {
9968 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
9969 	PMAP_ASSERT_STAGE1(pmap);
9970 
9971 	pmap_mask_set_locked(pmap, sva, eva, ATTR_S1_GP, set ? ATTR_S1_GP : 0,
9972 	    true);
9973 }
9974 
9975 int
9976 pmap_bti_set(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
9977 {
9978 	int error;
9979 
9980 	if (pmap->pm_bti == NULL)
9981 		return (0);
9982 	if (!ADDR_IS_CANONICAL(sva) || !ADDR_IS_CANONICAL(eva))
9983 		return (EINVAL);
9984 	if (pmap->pm_stage != PM_STAGE1)
9985 		return (EINVAL);
9986 	if (eva <= sva || ADDR_IS_KERNEL(eva))
9987 		return (EFAULT);
9988 
9989 	sva = trunc_page(sva);
9990 	eva = round_page(eva);
9991 	for (;;) {
9992 		PMAP_LOCK(pmap);
9993 		error = pmap_bti_assign(pmap, sva, eva);
9994 		if (error == 0)
9995 			pmap_bti_update_range(pmap, sva, eva, true);
9996 		PMAP_UNLOCK(pmap);
9997 		if (error != ENOMEM)
9998 			break;
9999 		vm_wait(NULL);
10000 	}
10001 	return (error);
10002 }
10003 
10004 #if defined(KASAN) || defined(KMSAN)
10005 static pd_entry_t	*pmap_san_early_l2;
10006 
10007 #define	SAN_BOOTSTRAP_L2_SIZE	(1 * L2_SIZE)
10008 #define	SAN_BOOTSTRAP_SIZE	(2 * PAGE_SIZE)
10009 static vm_offset_t __nosanitizeaddress
10010 pmap_san_enter_bootstrap_alloc_l2(void)
10011 {
10012 	static uint8_t bootstrap_data[SAN_BOOTSTRAP_L2_SIZE] __aligned(L2_SIZE);
10013 	static size_t offset = 0;
10014 	vm_offset_t addr;
10015 
10016 	if (offset + L2_SIZE > sizeof(bootstrap_data)) {
10017 		panic("%s: out of memory for the bootstrap shadow map L2 entries",
10018 		    __func__);
10019 	}
10020 
10021 	addr = (uintptr_t)&bootstrap_data[offset];
10022 	offset += L2_SIZE;
10023 	return (addr);
10024 }
10025 
10026 /*
10027  * SAN L1 + L2 pages, maybe L3 entries later?
10028  */
10029 static vm_offset_t __nosanitizeaddress
10030 pmap_san_enter_bootstrap_alloc_pages(int npages)
10031 {
10032 	static uint8_t bootstrap_data[SAN_BOOTSTRAP_SIZE] __aligned(PAGE_SIZE);
10033 	static size_t offset = 0;
10034 	vm_offset_t addr;
10035 
10036 	if (offset + (npages * PAGE_SIZE) > sizeof(bootstrap_data)) {
10037 		panic("%s: out of memory for the bootstrap shadow map",
10038 		    __func__);
10039 	}
10040 
10041 	addr = (uintptr_t)&bootstrap_data[offset];
10042 	offset += (npages * PAGE_SIZE);
10043 	return (addr);
10044 }
10045 
10046 static void __nosanitizeaddress
10047 pmap_san_enter_bootstrap(void)
10048 {
10049 	vm_offset_t freemempos;
10050 
10051 	/* L1, L2 */
10052 	freemempos = pmap_san_enter_bootstrap_alloc_pages(2);
10053 	bs_state.freemempos = freemempos;
10054 	bs_state.va = KASAN_MIN_ADDRESS;
10055 	pmap_bootstrap_l1_table(&bs_state);
10056 	pmap_san_early_l2 = bs_state.l2;
10057 }
10058 
10059 static vm_page_t
10060 pmap_san_enter_alloc_l3(void)
10061 {
10062 	vm_page_t m;
10063 
10064 	m = vm_page_alloc_noobj(VM_ALLOC_INTERRUPT | VM_ALLOC_WIRED |
10065 	    VM_ALLOC_ZERO);
10066 	if (m == NULL)
10067 		panic("%s: no memory to grow shadow map", __func__);
10068 	return (m);
10069 }
10070 
10071 static vm_page_t
10072 pmap_san_enter_alloc_l2(void)
10073 {
10074 	return (vm_page_alloc_noobj_contig(VM_ALLOC_WIRED | VM_ALLOC_ZERO,
10075 	    Ln_ENTRIES, 0, ~0ul, L2_SIZE, 0, VM_MEMATTR_DEFAULT));
10076 }
10077 
10078 void __nosanitizeaddress __nosanitizememory
10079 pmap_san_enter(vm_offset_t va)
10080 {
10081 	pd_entry_t *l1, *l2;
10082 	pt_entry_t *l3;
10083 	vm_page_t m;
10084 
10085 	if (virtual_avail == 0) {
10086 		vm_offset_t block;
10087 		int slot;
10088 		bool first;
10089 
10090 		/* Temporary shadow map prior to pmap_bootstrap(). */
10091 		first = pmap_san_early_l2 == NULL;
10092 		if (first)
10093 			pmap_san_enter_bootstrap();
10094 
10095 		l2 = pmap_san_early_l2;
10096 		slot = pmap_l2_index(va);
10097 
10098 		if ((pmap_load(&l2[slot]) & ATTR_DESCR_VALID) == 0) {
10099 			MPASS(first);
10100 			block = pmap_san_enter_bootstrap_alloc_l2();
10101 			pmap_store(&l2[slot],
10102 			    PHYS_TO_PTE(pmap_early_vtophys(block)) |
10103 			    PMAP_SAN_PTE_BITS | L2_BLOCK);
10104 			dmb(ishst);
10105 		}
10106 
10107 		return;
10108 	}
10109 
10110 	mtx_assert(&kernel_map->system_mtx, MA_OWNED);
10111 	l1 = pmap_l1(kernel_pmap, va);
10112 	MPASS(l1 != NULL);
10113 	if ((pmap_load(l1) & ATTR_DESCR_VALID) == 0) {
10114 		m = pmap_san_enter_alloc_l3();
10115 		pmap_store(l1, VM_PAGE_TO_PTE(m) | L1_TABLE);
10116 	}
10117 	l2 = pmap_l1_to_l2(l1, va);
10118 	if ((pmap_load(l2) & ATTR_DESCR_VALID) == 0) {
10119 		m = pmap_san_enter_alloc_l2();
10120 		if (m != NULL) {
10121 			pmap_store(l2, VM_PAGE_TO_PTE(m) |
10122 			    PMAP_SAN_PTE_BITS | L2_BLOCK);
10123 		} else {
10124 			m = pmap_san_enter_alloc_l3();
10125 			pmap_store(l2, VM_PAGE_TO_PTE(m) | L2_TABLE);
10126 		}
10127 		dmb(ishst);
10128 	}
10129 	if ((pmap_load(l2) & ATTR_DESCR_MASK) == L2_BLOCK)
10130 		return;
10131 	l3 = pmap_l2_to_l3(l2, va);
10132 	if ((pmap_load(l3) & ATTR_DESCR_VALID) != 0)
10133 		return;
10134 	m = pmap_san_enter_alloc_l3();
10135 	pmap_store(l3, VM_PAGE_TO_PTE(m) | PMAP_SAN_PTE_BITS | L3_PAGE);
10136 	dmb(ishst);
10137 }
10138 #endif /* KASAN || KMSAN */
10139 
10140 /*
10141  * Track a range of the kernel's virtual address space that is contiguous
10142  * in various mapping attributes.
10143  */
10144 struct pmap_kernel_map_range {
10145 	vm_offset_t sva;
10146 	pt_entry_t attrs;
10147 	int l3pages;
10148 	int l3contig;
10149 	int l2blocks;
10150 	int l2contig;
10151 	int l1blocks;
10152 };
10153 
10154 static void
10155 sysctl_kmaps_dump(struct sbuf *sb, struct pmap_kernel_map_range *range,
10156     vm_offset_t eva)
10157 {
10158 	const char *mode;
10159 	int index;
10160 
10161 	if (eva <= range->sva)
10162 		return;
10163 
10164 	index = range->attrs & ATTR_S1_IDX_MASK;
10165 	switch (index) {
10166 	case ATTR_S1_IDX(VM_MEMATTR_DEVICE_NP):
10167 		mode = "DEV-NP";
10168 		break;
10169 	case ATTR_S1_IDX(VM_MEMATTR_DEVICE):
10170 		mode = "DEV";
10171 		break;
10172 	case ATTR_S1_IDX(VM_MEMATTR_UNCACHEABLE):
10173 		mode = "UC";
10174 		break;
10175 	case ATTR_S1_IDX(VM_MEMATTR_WRITE_BACK):
10176 		mode = "WB";
10177 		break;
10178 	case ATTR_S1_IDX(VM_MEMATTR_WRITE_THROUGH):
10179 		mode = "WT";
10180 		break;
10181 	case ATTR_S1_IDX(VM_MEMATTR_TAGGED):
10182 		mode = "TAGGED";
10183 		break;
10184 	default:
10185 		printf(
10186 		    "%s: unknown memory type %x for range 0x%016lx-0x%016lx\n",
10187 		    __func__, index, range->sva, eva);
10188 		mode = "??";
10189 		break;
10190 	}
10191 
10192 	sbuf_printf(sb, "0x%016lx-0x%016lx r%c%c%c%c%c %6s %d %d %d %d %d\n",
10193 	    range->sva, eva,
10194 	    (range->attrs & ATTR_S1_AP_RW_BIT) == ATTR_S1_AP_RW ? 'w' : '-',
10195 	    (range->attrs & ATTR_S1_PXN) != 0 ? '-' : 'x',
10196 	    (range->attrs & ATTR_S1_UXN) != 0 ? '-' : 'X',
10197 	    (range->attrs & ATTR_S1_AP(ATTR_S1_AP_USER)) != 0 ? 'u' : 's',
10198 	    (range->attrs & ATTR_S1_GP) != 0 ? 'g' : '-',
10199 	    mode, range->l1blocks, range->l2contig, range->l2blocks,
10200 	    range->l3contig, range->l3pages);
10201 
10202 	/* Reset to sentinel value. */
10203 	range->sva = 0xfffffffffffffffful;
10204 }
10205 
10206 /*
10207  * Determine whether the attributes specified by a page table entry match those
10208  * being tracked by the current range.
10209  */
10210 static bool
10211 sysctl_kmaps_match(struct pmap_kernel_map_range *range, pt_entry_t attrs)
10212 {
10213 
10214 	return (range->attrs == attrs);
10215 }
10216 
10217 static void
10218 sysctl_kmaps_reinit(struct pmap_kernel_map_range *range, vm_offset_t va,
10219     pt_entry_t attrs)
10220 {
10221 
10222 	memset(range, 0, sizeof(*range));
10223 	range->sva = va;
10224 	range->attrs = attrs;
10225 }
10226 
10227 /* Get the block/page attributes that correspond to the table attributes */
10228 static pt_entry_t
10229 sysctl_kmaps_table_attrs(pd_entry_t table)
10230 {
10231 	pt_entry_t attrs;
10232 
10233 	attrs = 0;
10234 	if ((table & TATTR_UXN_TABLE) != 0)
10235 		attrs |= ATTR_S1_UXN;
10236 	if ((table & TATTR_PXN_TABLE) != 0)
10237 		attrs |= ATTR_S1_PXN;
10238 	if ((table & TATTR_AP_TABLE_RO) != 0)
10239 		attrs |= ATTR_S1_AP(ATTR_S1_AP_RO);
10240 
10241 	return (attrs);
10242 }
10243 
10244 /* Read the block/page attributes we care about */
10245 static pt_entry_t
10246 sysctl_kmaps_block_attrs(pt_entry_t block)
10247 {
10248 	return (block & (ATTR_S1_AP_MASK | ATTR_S1_XN | ATTR_S1_IDX_MASK |
10249 	    ATTR_S1_GP));
10250 }
10251 
10252 /*
10253  * Given a leaf PTE, derive the mapping's attributes.  If they do not match
10254  * those of the current run, dump the address range and its attributes, and
10255  * begin a new run.
10256  */
10257 static void
10258 sysctl_kmaps_check(struct sbuf *sb, struct pmap_kernel_map_range *range,
10259     vm_offset_t va, pd_entry_t l0e, pd_entry_t l1e, pd_entry_t l2e,
10260     pt_entry_t l3e)
10261 {
10262 	pt_entry_t attrs;
10263 
10264 	attrs = sysctl_kmaps_table_attrs(l0e);
10265 
10266 	if ((l1e & ATTR_DESCR_TYPE_MASK) == ATTR_DESCR_TYPE_BLOCK) {
10267 		attrs |= sysctl_kmaps_block_attrs(l1e);
10268 		goto done;
10269 	}
10270 	attrs |= sysctl_kmaps_table_attrs(l1e);
10271 
10272 	if ((l2e & ATTR_DESCR_TYPE_MASK) == ATTR_DESCR_TYPE_BLOCK) {
10273 		attrs |= sysctl_kmaps_block_attrs(l2e);
10274 		goto done;
10275 	}
10276 	attrs |= sysctl_kmaps_table_attrs(l2e);
10277 	attrs |= sysctl_kmaps_block_attrs(l3e);
10278 
10279 done:
10280 	if (range->sva > va || !sysctl_kmaps_match(range, attrs)) {
10281 		sysctl_kmaps_dump(sb, range, va);
10282 		sysctl_kmaps_reinit(range, va, attrs);
10283 	}
10284 }
10285 
10286 static int
10287 sysctl_kmaps(SYSCTL_HANDLER_ARGS)
10288 {
10289 	struct pmap_kernel_map_range range;
10290 	struct sbuf sbuf, *sb;
10291 	pd_entry_t l0e, *l1, l1e, *l2, l2e;
10292 	pt_entry_t *l3, l3e;
10293 	vm_offset_t sva;
10294 	vm_paddr_t pa;
10295 	int error, i, j, k, l;
10296 
10297 	error = sysctl_wire_old_buffer(req, 0);
10298 	if (error != 0)
10299 		return (error);
10300 	sb = &sbuf;
10301 	sbuf_new_for_sysctl(sb, NULL, PAGE_SIZE, req);
10302 
10303 	/* Sentinel value. */
10304 	range.sva = 0xfffffffffffffffful;
10305 
10306 	/*
10307 	 * Iterate over the kernel page tables without holding the kernel pmap
10308 	 * lock.  Kernel page table pages are never freed, so at worst we will
10309 	 * observe inconsistencies in the output.
10310 	 */
10311 	for (sva = 0xffff000000000000ul, i = pmap_l0_index(sva); i < Ln_ENTRIES;
10312 	    i++) {
10313 		if (i == pmap_l0_index(DMAP_MIN_ADDRESS))
10314 			sbuf_printf(sb, "\nDirect map:\n");
10315 		else if (i == pmap_l0_index(VM_MIN_KERNEL_ADDRESS))
10316 			sbuf_printf(sb, "\nKernel map:\n");
10317 #ifdef KASAN
10318 		else if (i == pmap_l0_index(KASAN_MIN_ADDRESS))
10319 			sbuf_printf(sb, "\nKASAN shadow map:\n");
10320 #endif
10321 #ifdef KMSAN
10322 		else if (i == pmap_l0_index(KMSAN_SHAD_MIN_ADDRESS))
10323 			sbuf_printf(sb, "\nKMSAN shadow map:\n");
10324 		else if (i == pmap_l0_index(KMSAN_ORIG_MIN_ADDRESS))
10325 			sbuf_printf(sb, "\nKMSAN origin map:\n");
10326 #endif
10327 
10328 		l0e = kernel_pmap->pm_l0[i];
10329 		if ((l0e & ATTR_DESCR_VALID) == 0) {
10330 			sysctl_kmaps_dump(sb, &range, sva);
10331 			sva += L0_SIZE;
10332 			continue;
10333 		}
10334 		pa = PTE_TO_PHYS(l0e);
10335 		l1 = PHYS_TO_DMAP(pa);
10336 
10337 		for (j = pmap_l1_index(sva); j < Ln_ENTRIES; j++) {
10338 			l1e = l1[j];
10339 			if ((l1e & ATTR_DESCR_VALID) == 0) {
10340 				sysctl_kmaps_dump(sb, &range, sva);
10341 				sva += L1_SIZE;
10342 				continue;
10343 			}
10344 			if ((l1e & ATTR_DESCR_MASK) == L1_BLOCK) {
10345 				PMAP_ASSERT_L1_BLOCKS_SUPPORTED;
10346 				sysctl_kmaps_check(sb, &range, sva, l0e, l1e,
10347 				    0, 0);
10348 				range.l1blocks++;
10349 				sva += L1_SIZE;
10350 				continue;
10351 			}
10352 			pa = PTE_TO_PHYS(l1e);
10353 			l2 = PHYS_TO_DMAP(pa);
10354 
10355 			for (k = pmap_l2_index(sva); k < Ln_ENTRIES; k++) {
10356 				l2e = l2[k];
10357 				if ((l2e & ATTR_DESCR_VALID) == 0) {
10358 					sysctl_kmaps_dump(sb, &range, sva);
10359 					sva += L2_SIZE;
10360 					continue;
10361 				}
10362 				if ((l2e & ATTR_DESCR_MASK) == L2_BLOCK) {
10363 					sysctl_kmaps_check(sb, &range, sva,
10364 					    l0e, l1e, l2e, 0);
10365 					if ((l2e & ATTR_CONTIGUOUS) != 0)
10366 						range.l2contig +=
10367 						    k % L2C_ENTRIES == 0 ?
10368 						    1 : 0;
10369 					else
10370 						range.l2blocks++;
10371 					sva += L2_SIZE;
10372 					continue;
10373 				}
10374 				pa = PTE_TO_PHYS(l2e);
10375 				l3 = PHYS_TO_DMAP(pa);
10376 
10377 				for (l = pmap_l3_index(sva); l < Ln_ENTRIES;
10378 				    l++, sva += L3_SIZE) {
10379 					l3e = l3[l];
10380 					if ((l3e & ATTR_DESCR_VALID) == 0) {
10381 						sysctl_kmaps_dump(sb, &range,
10382 						    sva);
10383 						continue;
10384 					}
10385 					sysctl_kmaps_check(sb, &range, sva,
10386 					    l0e, l1e, l2e, l3e);
10387 					if ((l3e & ATTR_CONTIGUOUS) != 0)
10388 						range.l3contig +=
10389 						    l % L3C_ENTRIES == 0 ?
10390 						    1 : 0;
10391 					else
10392 						range.l3pages++;
10393 				}
10394 			}
10395 		}
10396 	}
10397 
10398 	error = sbuf_finish(sb);
10399 	sbuf_delete(sb);
10400 	return (error);
10401 }
10402 SYSCTL_OID(_vm_pmap, OID_AUTO, kernel_maps,
10403     CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE | CTLFLAG_SKIP,
10404     NULL, 0, sysctl_kmaps, "A",
10405     "Dump kernel address layout");
10406 
10407 
10408 void pagezero_simple(void *);
10409 void pagezero_cache(void *);
10410 void pagezero_mops(void *);
10411 
10412 DEFINE_IFUNC(static, void, pagezero, (void *))
10413 {
10414 	uint32_t dczid_el0;
10415 
10416 	dczid_el0 = READ_SPECIALREG(dczid_el0);
10417 
10418 	if (elf_hwcap2 & HWCAP2_MOPS)
10419 		return (pagezero_mops);
10420 	else if ((dczid_el0 & DCZID_DZP) == 0)
10421 		return (pagezero_cache);
10422 	else
10423 		return (pagezero_simple);
10424 }
10425