xref: /freebsd/sys/arm/arm/pmap-v6.c (revision 5b9c547c)
1 /* From: $NetBSD: pmap.c,v 1.148 2004/04/03 04:35:48 bsh Exp $ */
2 /*-
3  * Copyright 2011 Semihalf
4  * Copyright 2004 Olivier Houchard.
5  * Copyright 2003 Wasabi Systems, Inc.
6  * All rights reserved.
7  *
8  * Written by Steve C. Woodford for Wasabi Systems, Inc.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *      This product includes software developed for the NetBSD Project by
21  *      Wasabi Systems, Inc.
22  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
23  *    or promote products derived from this software without specific prior
24  *    written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  *
38  * From: FreeBSD: src/sys/arm/arm/pmap.c,v 1.113 2009/07/24 13:50:29
39  */
40 
41 /*-
42  * Copyright (c) 2002-2003 Wasabi Systems, Inc.
43  * Copyright (c) 2001 Richard Earnshaw
44  * Copyright (c) 2001-2002 Christopher Gilbert
45  * All rights reserved.
46  *
47  * 1. Redistributions of source code must retain the above copyright
48  *    notice, this list of conditions and the following disclaimer.
49  * 2. Redistributions in binary form must reproduce the above copyright
50  *    notice, this list of conditions and the following disclaimer in the
51  *    documentation and/or other materials provided with the distribution.
52  * 3. The name of the company nor the name of the author may be used to
53  *    endorse or promote products derived from this software without specific
54  *    prior written permission.
55  *
56  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
57  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
58  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
59  * IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
60  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
61  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
62  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
63  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
64  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
65  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
66  * SUCH DAMAGE.
67  */
68 /*-
69  * Copyright (c) 1999 The NetBSD Foundation, Inc.
70  * All rights reserved.
71  *
72  * This code is derived from software contributed to The NetBSD Foundation
73  * by Charles M. Hannum.
74  *
75  * Redistribution and use in source and binary forms, with or without
76  * modification, are permitted provided that the following conditions
77  * are met:
78  * 1. Redistributions of source code must retain the above copyright
79  *    notice, this list of conditions and the following disclaimer.
80  * 2. Redistributions in binary form must reproduce the above copyright
81  *    notice, this list of conditions and the following disclaimer in the
82  *    documentation and/or other materials provided with the distribution.
83  *
84  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
85  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
86  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
87  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
88  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
89  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
90  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
91  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
92  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
93  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
94  * POSSIBILITY OF SUCH DAMAGE.
95  */
96 
97 /*-
98  * Copyright (c) 1994-1998 Mark Brinicombe.
99  * Copyright (c) 1994 Brini.
100  * All rights reserved.
101  *
102  * This code is derived from software written for Brini by Mark Brinicombe
103  *
104  * Redistribution and use in source and binary forms, with or without
105  * modification, are permitted provided that the following conditions
106  * are met:
107  * 1. Redistributions of source code must retain the above copyright
108  *    notice, this list of conditions and the following disclaimer.
109  * 2. Redistributions in binary form must reproduce the above copyright
110  *    notice, this list of conditions and the following disclaimer in the
111  *    documentation and/or other materials provided with the distribution.
112  * 3. All advertising materials mentioning features or use of this software
113  *    must display the following acknowledgement:
114  *      This product includes software developed by Mark Brinicombe.
115  * 4. The name of the author may not be used to endorse or promote products
116  *    derived from this software without specific prior written permission.
117  *
118  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
119  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
120  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
121  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
122  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
123  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
124  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
125  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
126  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
127  *
128  * RiscBSD kernel project
129  *
130  * pmap.c
131  *
132  * Machine dependant vm stuff
133  *
134  * Created      : 20/09/94
135  */
136 
137 /*
138  * Special compilation symbols
139  * PMAP_DEBUG           - Build in pmap_debug_level code
140  *
141  * Note that pmap_mapdev() and pmap_unmapdev() are implemented in arm/devmap.c
142 */
143 /* Include header files */
144 
145 #include "opt_vm.h"
146 #include "opt_pmap.h"
147 
148 #include <sys/cdefs.h>
149 __FBSDID("$FreeBSD$");
150 #include <sys/param.h>
151 #include <sys/systm.h>
152 #include <sys/kernel.h>
153 #include <sys/ktr.h>
154 #include <sys/lock.h>
155 #include <sys/proc.h>
156 #include <sys/malloc.h>
157 #include <sys/msgbuf.h>
158 #include <sys/mutex.h>
159 #include <sys/vmmeter.h>
160 #include <sys/mman.h>
161 #include <sys/rwlock.h>
162 #include <sys/smp.h>
163 #include <sys/sched.h>
164 #include <sys/sysctl.h>
165 
166 #include <vm/vm.h>
167 #include <vm/vm_param.h>
168 #include <vm/uma.h>
169 #include <vm/pmap.h>
170 #include <vm/vm_kern.h>
171 #include <vm/vm_object.h>
172 #include <vm/vm_map.h>
173 #include <vm/vm_page.h>
174 #include <vm/vm_pageout.h>
175 #include <vm/vm_phys.h>
176 #include <vm/vm_extern.h>
177 #include <vm/vm_reserv.h>
178 
179 #include <machine/md_var.h>
180 #include <machine/cpu.h>
181 #include <machine/cpufunc.h>
182 #include <machine/pcb.h>
183 
184 #ifdef DEBUG
185 extern int last_fault_code;
186 #endif
187 
188 #ifdef PMAP_DEBUG
189 #define PDEBUG(_lev_,_stat_) \
190         if (pmap_debug_level >= (_lev_)) \
191                 ((_stat_))
192 #define dprintf printf
193 
194 int pmap_debug_level = 0;
195 #define PMAP_INLINE
196 #else   /* PMAP_DEBUG */
197 #define PDEBUG(_lev_,_stat_) /* Nothing */
198 #define dprintf(x, arg...)
199 #define PMAP_INLINE __inline
200 #endif  /* PMAP_DEBUG */
201 
202 #ifdef PV_STATS
203 #define PV_STAT(x)	do { x ; } while (0)
204 #else
205 #define PV_STAT(x)	do { } while (0)
206 #endif
207 
208 #define	pa_to_pvh(pa)	(&pv_table[pa_index(pa)])
209 
210 #ifdef ARM_L2_PIPT
211 #define pmap_l2cache_wbinv_range(va, pa, size) cpu_l2cache_wbinv_range((pa), (size))
212 #define pmap_l2cache_inv_range(va, pa, size) cpu_l2cache_inv_range((pa), (size))
213 #else
214 #define pmap_l2cache_wbinv_range(va, pa, size) cpu_l2cache_wbinv_range((va), (size))
215 #define pmap_l2cache_inv_range(va, pa, size) cpu_l2cache_inv_range((va), (size))
216 #endif
217 
218 extern struct pv_addr systempage;
219 
220 /*
221  * Internal function prototypes
222  */
223 
224 static PMAP_INLINE
225 struct pv_entry		*pmap_find_pv(struct md_page *, pmap_t, vm_offset_t);
226 static void		pmap_free_pv_chunk(struct pv_chunk *pc);
227 static void		pmap_free_pv_entry(pmap_t pmap, pv_entry_t pv);
228 static pv_entry_t 	pmap_get_pv_entry(pmap_t pmap, boolean_t try);
229 static vm_page_t 	pmap_pv_reclaim(pmap_t locked_pmap);
230 static boolean_t	pmap_pv_insert_section(pmap_t, vm_offset_t,
231     vm_paddr_t);
232 static struct pv_entry	*pmap_remove_pv(struct vm_page *, pmap_t, vm_offset_t);
233 static int		pmap_pvh_wired_mappings(struct md_page *, int);
234 
235 static int		pmap_enter_locked(pmap_t, vm_offset_t, vm_page_t,
236     vm_prot_t, u_int);
237 static vm_paddr_t	pmap_extract_locked(pmap_t pmap, vm_offset_t va);
238 static void		pmap_alloc_l1(pmap_t);
239 static void		pmap_free_l1(pmap_t);
240 
241 static void		pmap_map_section(pmap_t, vm_offset_t, vm_offset_t,
242     vm_prot_t, boolean_t);
243 static void		pmap_promote_section(pmap_t, vm_offset_t);
244 static boolean_t	pmap_demote_section(pmap_t, vm_offset_t);
245 static boolean_t	pmap_enter_section(pmap_t, vm_offset_t, vm_page_t,
246     vm_prot_t);
247 static void		pmap_remove_section(pmap_t, vm_offset_t);
248 
249 static int		pmap_clearbit(struct vm_page *, u_int);
250 
251 static struct l2_bucket *pmap_get_l2_bucket(pmap_t, vm_offset_t);
252 static struct l2_bucket *pmap_alloc_l2_bucket(pmap_t, vm_offset_t);
253 static void		pmap_free_l2_bucket(pmap_t, struct l2_bucket *, u_int);
254 static vm_offset_t	kernel_pt_lookup(vm_paddr_t);
255 
256 static MALLOC_DEFINE(M_VMPMAP, "pmap", "PMAP L1");
257 
258 vm_offset_t virtual_avail;	/* VA of first avail page (after kernel bss) */
259 vm_offset_t virtual_end;	/* VA of last avail page (end of kernel AS) */
260 vm_offset_t pmap_curmaxkvaddr;
261 vm_paddr_t kernel_l1pa;
262 
263 vm_offset_t kernel_vm_end = 0;
264 
265 vm_offset_t vm_max_kernel_address;
266 
267 struct pmap kernel_pmap_store;
268 
269 /*
270  * Resources for quickly copying and zeroing pages using virtual address space
271  * and page table entries that are pre-allocated per-CPU by pmap_init().
272  */
273 struct czpages {
274 	struct	mtx 	lock;
275 	pt_entry_t	*srcptep;
276 	pt_entry_t	*dstptep;
277 	vm_offset_t	srcva;
278 	vm_offset_t	dstva;
279 };
280 static struct czpages cpu_czpages[MAXCPU];
281 
282 static void		pmap_init_l1(struct l1_ttable *, pd_entry_t *);
283 /*
284  * These routines are called when the CPU type is identified to set up
285  * the PTE prototypes, cache modes, etc.
286  *
287  * The variables are always here, just in case LKMs need to reference
288  * them (though, they shouldn't).
289  */
290 static void pmap_set_prot(pt_entry_t *pte, vm_prot_t prot, uint8_t user);
291 pt_entry_t	pte_l1_s_cache_mode;
292 pt_entry_t	pte_l1_s_cache_mode_pt;
293 
294 pt_entry_t	pte_l2_l_cache_mode;
295 pt_entry_t	pte_l2_l_cache_mode_pt;
296 
297 pt_entry_t	pte_l2_s_cache_mode;
298 pt_entry_t	pte_l2_s_cache_mode_pt;
299 
300 struct msgbuf *msgbufp = 0;
301 
302 /*
303  * Crashdump maps.
304  */
305 static caddr_t crashdumpmap;
306 
307 extern void bcopy_page(vm_offset_t, vm_offset_t);
308 extern void bzero_page(vm_offset_t);
309 
310 char *_tmppt;
311 
312 /*
313  * Metadata for L1 translation tables.
314  */
315 struct l1_ttable {
316 	/* Entry on the L1 Table list */
317 	SLIST_ENTRY(l1_ttable) l1_link;
318 
319 	/* Entry on the L1 Least Recently Used list */
320 	TAILQ_ENTRY(l1_ttable) l1_lru;
321 
322 	/* Track how many domains are allocated from this L1 */
323 	volatile u_int l1_domain_use_count;
324 
325 	/*
326 	 * A free-list of domain numbers for this L1.
327 	 * We avoid using ffs() and a bitmap to track domains since ffs()
328 	 * is slow on ARM.
329 	 */
330 	u_int8_t l1_domain_first;
331 	u_int8_t l1_domain_free[PMAP_DOMAINS];
332 
333 	/* Physical address of this L1 page table */
334 	vm_paddr_t l1_physaddr;
335 
336 	/* KVA of this L1 page table */
337 	pd_entry_t *l1_kva;
338 };
339 
340 /*
341  * Convert a virtual address into its L1 table index. That is, the
342  * index used to locate the L2 descriptor table pointer in an L1 table.
343  * This is basically used to index l1->l1_kva[].
344  *
345  * Each L2 descriptor table represents 1MB of VA space.
346  */
347 #define	L1_IDX(va)		(((vm_offset_t)(va)) >> L1_S_SHIFT)
348 
349 /*
350  * L1 Page Tables are tracked using a Least Recently Used list.
351  *  - New L1s are allocated from the HEAD.
352  *  - Freed L1s are added to the TAIl.
353  *  - Recently accessed L1s (where an 'access' is some change to one of
354  *    the userland pmaps which owns this L1) are moved to the TAIL.
355  */
356 static TAILQ_HEAD(, l1_ttable) l1_lru_list;
357 /*
358  * A list of all L1 tables
359  */
360 static SLIST_HEAD(, l1_ttable) l1_list;
361 static struct mtx l1_lru_lock;
362 
363 /*
364  * The l2_dtable tracks L2_BUCKET_SIZE worth of L1 slots.
365  *
366  * This is normally 16MB worth L2 page descriptors for any given pmap.
367  * Reference counts are maintained for L2 descriptors so they can be
368  * freed when empty.
369  */
370 struct l2_dtable {
371 	/* The number of L2 page descriptors allocated to this l2_dtable */
372 	u_int l2_occupancy;
373 
374 	/* List of L2 page descriptors */
375 	struct l2_bucket {
376 		pt_entry_t *l2b_kva;	/* KVA of L2 Descriptor Table */
377 		vm_paddr_t l2b_phys;	/* Physical address of same */
378 		u_short l2b_l1idx;	/* This L2 table's L1 index */
379 		u_short l2b_occupancy;	/* How many active descriptors */
380 	} l2_bucket[L2_BUCKET_SIZE];
381 };
382 
383 /* pmap_kenter_internal flags */
384 #define KENTER_CACHE	0x1
385 #define KENTER_DEVICE	0x2
386 #define KENTER_USER	0x4
387 
388 /*
389  * Given an L1 table index, calculate the corresponding l2_dtable index
390  * and bucket index within the l2_dtable.
391  */
392 #define	L2_IDX(l1idx)		(((l1idx) >> L2_BUCKET_LOG2) & \
393 				 (L2_SIZE - 1))
394 #define	L2_BUCKET(l1idx)	((l1idx) & (L2_BUCKET_SIZE - 1))
395 
396 /*
397  * Given a virtual address, this macro returns the
398  * virtual address required to drop into the next L2 bucket.
399  */
400 #define	L2_NEXT_BUCKET(va)	(((va) & L1_S_FRAME) + L1_S_SIZE)
401 
402 /*
403  * We try to map the page tables write-through, if possible.  However, not
404  * all CPUs have a write-through cache mode, so on those we have to sync
405  * the cache when we frob page tables.
406  *
407  * We try to evaluate this at compile time, if possible.  However, it's
408  * not always possible to do that, hence this run-time var.
409  */
410 int	pmap_needs_pte_sync;
411 
412 /*
413  * Macro to determine if a mapping might be resident in the
414  * instruction cache and/or TLB
415  */
416 #define	PTE_BEEN_EXECD(pte)  (L2_S_EXECUTABLE(pte) && L2_S_REFERENCED(pte))
417 
418 /*
419  * Macro to determine if a mapping might be resident in the
420  * data cache and/or TLB
421  */
422 #define	PTE_BEEN_REFD(pte)   (L2_S_REFERENCED(pte))
423 
424 #ifndef PMAP_SHPGPERPROC
425 #define PMAP_SHPGPERPROC 200
426 #endif
427 
428 #define pmap_is_current(pm)	((pm) == pmap_kernel() || \
429             curproc->p_vmspace->vm_map.pmap == (pm))
430 
431 /*
432  * Data for the pv entry allocation mechanism
433  */
434 static TAILQ_HEAD(pch, pv_chunk) pv_chunks = TAILQ_HEAD_INITIALIZER(pv_chunks);
435 static int pv_entry_count, pv_entry_max, pv_entry_high_water;
436 static struct md_page *pv_table;
437 static int shpgperproc = PMAP_SHPGPERPROC;
438 
439 struct pv_chunk *pv_chunkbase;		/* KVA block for pv_chunks */
440 int pv_maxchunks;			/* How many chunks we have KVA for */
441 vm_offset_t pv_vafree;			/* Freelist stored in the PTE */
442 
443 static __inline struct pv_chunk *
444 pv_to_chunk(pv_entry_t pv)
445 {
446 
447 	return ((struct pv_chunk *)((uintptr_t)pv & ~(uintptr_t)PAGE_MASK));
448 }
449 
450 #define PV_PMAP(pv) (pv_to_chunk(pv)->pc_pmap)
451 
452 CTASSERT(sizeof(struct pv_chunk) == PAGE_SIZE);
453 CTASSERT(_NPCM == 8);
454 CTASSERT(_NPCPV == 252);
455 
456 #define	PC_FREE0_6	0xfffffffful	/* Free values for index 0 through 6 */
457 #define	PC_FREE7	0x0ffffffful	/* Free values for index 7 */
458 
459 static const uint32_t pc_freemask[_NPCM] = {
460 	PC_FREE0_6, PC_FREE0_6, PC_FREE0_6,
461 	PC_FREE0_6, PC_FREE0_6, PC_FREE0_6,
462 	PC_FREE0_6, PC_FREE7
463 };
464 
465 static SYSCTL_NODE(_vm, OID_AUTO, pmap, CTLFLAG_RD, 0, "VM/pmap parameters");
466 
467 /* Superpages utilization enabled = 1 / disabled = 0 */
468 static int sp_enabled = 1;
469 SYSCTL_INT(_vm_pmap, OID_AUTO, sp_enabled, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &sp_enabled, 0,
470     "Are large page mappings enabled?");
471 
472 SYSCTL_INT(_vm_pmap, OID_AUTO, pv_entry_count, CTLFLAG_RD, &pv_entry_count, 0,
473     "Current number of pv entries");
474 
475 #ifdef PV_STATS
476 static int pc_chunk_count, pc_chunk_allocs, pc_chunk_frees, pc_chunk_tryfail;
477 
478 SYSCTL_INT(_vm_pmap, OID_AUTO, pc_chunk_count, CTLFLAG_RD, &pc_chunk_count, 0,
479     "Current number of pv entry chunks");
480 SYSCTL_INT(_vm_pmap, OID_AUTO, pc_chunk_allocs, CTLFLAG_RD, &pc_chunk_allocs, 0,
481     "Current number of pv entry chunks allocated");
482 SYSCTL_INT(_vm_pmap, OID_AUTO, pc_chunk_frees, CTLFLAG_RD, &pc_chunk_frees, 0,
483     "Current number of pv entry chunks frees");
484 SYSCTL_INT(_vm_pmap, OID_AUTO, pc_chunk_tryfail, CTLFLAG_RD, &pc_chunk_tryfail, 0,
485     "Number of times tried to get a chunk page but failed.");
486 
487 static long pv_entry_frees, pv_entry_allocs;
488 static int pv_entry_spare;
489 
490 SYSCTL_LONG(_vm_pmap, OID_AUTO, pv_entry_frees, CTLFLAG_RD, &pv_entry_frees, 0,
491     "Current number of pv entry frees");
492 SYSCTL_LONG(_vm_pmap, OID_AUTO, pv_entry_allocs, CTLFLAG_RD, &pv_entry_allocs, 0,
493     "Current number of pv entry allocs");
494 SYSCTL_INT(_vm_pmap, OID_AUTO, pv_entry_spare, CTLFLAG_RD, &pv_entry_spare, 0,
495     "Current number of spare pv entries");
496 #endif
497 
498 uma_zone_t l2zone;
499 static uma_zone_t l2table_zone;
500 static vm_offset_t pmap_kernel_l2dtable_kva;
501 static vm_offset_t pmap_kernel_l2ptp_kva;
502 static vm_paddr_t pmap_kernel_l2ptp_phys;
503 static struct rwlock pvh_global_lock;
504 
505 int l1_mem_types[] = {
506 	ARM_L1S_STRONG_ORD,
507 	ARM_L1S_DEVICE_NOSHARE,
508 	ARM_L1S_DEVICE_SHARE,
509 	ARM_L1S_NRML_NOCACHE,
510 	ARM_L1S_NRML_IWT_OWT,
511 	ARM_L1S_NRML_IWB_OWB,
512 	ARM_L1S_NRML_IWBA_OWBA
513 };
514 
515 int l2l_mem_types[] = {
516 	ARM_L2L_STRONG_ORD,
517 	ARM_L2L_DEVICE_NOSHARE,
518 	ARM_L2L_DEVICE_SHARE,
519 	ARM_L2L_NRML_NOCACHE,
520 	ARM_L2L_NRML_IWT_OWT,
521 	ARM_L2L_NRML_IWB_OWB,
522 	ARM_L2L_NRML_IWBA_OWBA
523 };
524 
525 int l2s_mem_types[] = {
526 	ARM_L2S_STRONG_ORD,
527 	ARM_L2S_DEVICE_NOSHARE,
528 	ARM_L2S_DEVICE_SHARE,
529 	ARM_L2S_NRML_NOCACHE,
530 	ARM_L2S_NRML_IWT_OWT,
531 	ARM_L2S_NRML_IWB_OWB,
532 	ARM_L2S_NRML_IWBA_OWBA
533 };
534 
535 /*
536  * This list exists for the benefit of pmap_map_chunk().  It keeps track
537  * of the kernel L2 tables during bootstrap, so that pmap_map_chunk() can
538  * find them as necessary.
539  *
540  * Note that the data on this list MUST remain valid after initarm() returns,
541  * as pmap_bootstrap() uses it to contruct L2 table metadata.
542  */
543 SLIST_HEAD(, pv_addr) kernel_pt_list = SLIST_HEAD_INITIALIZER(kernel_pt_list);
544 
545 static void
546 pmap_init_l1(struct l1_ttable *l1, pd_entry_t *l1pt)
547 {
548 	int i;
549 
550 	l1->l1_kva = l1pt;
551 	l1->l1_domain_use_count = 0;
552 	l1->l1_domain_first = 0;
553 
554 	for (i = 0; i < PMAP_DOMAINS; i++)
555 		l1->l1_domain_free[i] = i + 1;
556 
557 	/*
558 	 * Copy the kernel's L1 entries to each new L1.
559 	 */
560 	if (l1pt != pmap_kernel()->pm_l1->l1_kva)
561 		memcpy(l1pt, pmap_kernel()->pm_l1->l1_kva, L1_TABLE_SIZE);
562 
563 	if ((l1->l1_physaddr = pmap_extract(pmap_kernel(), (vm_offset_t)l1pt)) == 0)
564 		panic("pmap_init_l1: can't get PA of L1 at %p", l1pt);
565 	SLIST_INSERT_HEAD(&l1_list, l1, l1_link);
566 	TAILQ_INSERT_TAIL(&l1_lru_list, l1, l1_lru);
567 }
568 
569 static vm_offset_t
570 kernel_pt_lookup(vm_paddr_t pa)
571 {
572 	struct pv_addr *pv;
573 
574 	SLIST_FOREACH(pv, &kernel_pt_list, pv_list) {
575 		if (pv->pv_pa == pa)
576 			return (pv->pv_va);
577 	}
578 	return (0);
579 }
580 
581 void
582 pmap_pte_init_mmu_v6(void)
583 {
584 
585 	if (PTE_PAGETABLE >= 3)
586 		pmap_needs_pte_sync = 1;
587 	pte_l1_s_cache_mode = l1_mem_types[PTE_CACHE];
588 	pte_l2_l_cache_mode = l2l_mem_types[PTE_CACHE];
589 	pte_l2_s_cache_mode = l2s_mem_types[PTE_CACHE];
590 
591 	pte_l1_s_cache_mode_pt = l1_mem_types[PTE_PAGETABLE];
592 	pte_l2_l_cache_mode_pt = l2l_mem_types[PTE_PAGETABLE];
593 	pte_l2_s_cache_mode_pt = l2s_mem_types[PTE_PAGETABLE];
594 
595 }
596 
597 /*
598  * Allocate an L1 translation table for the specified pmap.
599  * This is called at pmap creation time.
600  */
601 static void
602 pmap_alloc_l1(pmap_t pmap)
603 {
604 	struct l1_ttable *l1;
605 	u_int8_t domain;
606 
607 	/*
608 	 * Remove the L1 at the head of the LRU list
609 	 */
610 	mtx_lock(&l1_lru_lock);
611 	l1 = TAILQ_FIRST(&l1_lru_list);
612 	TAILQ_REMOVE(&l1_lru_list, l1, l1_lru);
613 
614 	/*
615 	 * Pick the first available domain number, and update
616 	 * the link to the next number.
617 	 */
618 	domain = l1->l1_domain_first;
619 	l1->l1_domain_first = l1->l1_domain_free[domain];
620 
621 	/*
622 	 * If there are still free domain numbers in this L1,
623 	 * put it back on the TAIL of the LRU list.
624 	 */
625 	if (++l1->l1_domain_use_count < PMAP_DOMAINS)
626 		TAILQ_INSERT_TAIL(&l1_lru_list, l1, l1_lru);
627 
628 	mtx_unlock(&l1_lru_lock);
629 
630 	/*
631 	 * Fix up the relevant bits in the pmap structure
632 	 */
633 	pmap->pm_l1 = l1;
634 	pmap->pm_domain = domain + 1;
635 }
636 
637 /*
638  * Free an L1 translation table.
639  * This is called at pmap destruction time.
640  */
641 static void
642 pmap_free_l1(pmap_t pmap)
643 {
644 	struct l1_ttable *l1 = pmap->pm_l1;
645 
646 	mtx_lock(&l1_lru_lock);
647 
648 	/*
649 	 * If this L1 is currently on the LRU list, remove it.
650 	 */
651 	if (l1->l1_domain_use_count < PMAP_DOMAINS)
652 		TAILQ_REMOVE(&l1_lru_list, l1, l1_lru);
653 
654 	/*
655 	 * Free up the domain number which was allocated to the pmap
656 	 */
657 	l1->l1_domain_free[pmap->pm_domain - 1] = l1->l1_domain_first;
658 	l1->l1_domain_first = pmap->pm_domain - 1;
659 	l1->l1_domain_use_count--;
660 
661 	/*
662 	 * The L1 now must have at least 1 free domain, so add
663 	 * it back to the LRU list. If the use count is zero,
664 	 * put it at the head of the list, otherwise it goes
665 	 * to the tail.
666 	 */
667 	if (l1->l1_domain_use_count == 0) {
668 		TAILQ_INSERT_HEAD(&l1_lru_list, l1, l1_lru);
669 	}	else
670 		TAILQ_INSERT_TAIL(&l1_lru_list, l1, l1_lru);
671 
672 	mtx_unlock(&l1_lru_lock);
673 }
674 
675 /*
676  * Returns a pointer to the L2 bucket associated with the specified pmap
677  * and VA, or NULL if no L2 bucket exists for the address.
678  */
679 static PMAP_INLINE struct l2_bucket *
680 pmap_get_l2_bucket(pmap_t pmap, vm_offset_t va)
681 {
682 	struct l2_dtable *l2;
683 	struct l2_bucket *l2b;
684 	u_short l1idx;
685 
686 	l1idx = L1_IDX(va);
687 
688 	if ((l2 = pmap->pm_l2[L2_IDX(l1idx)]) == NULL ||
689 	    (l2b = &l2->l2_bucket[L2_BUCKET(l1idx)])->l2b_kva == NULL)
690 		return (NULL);
691 
692 	return (l2b);
693 }
694 
695 /*
696  * Returns a pointer to the L2 bucket associated with the specified pmap
697  * and VA.
698  *
699  * If no L2 bucket exists, perform the necessary allocations to put an L2
700  * bucket/page table in place.
701  *
702  * Note that if a new L2 bucket/page was allocated, the caller *must*
703  * increment the bucket occupancy counter appropriately *before*
704  * releasing the pmap's lock to ensure no other thread or cpu deallocates
705  * the bucket/page in the meantime.
706  */
707 static struct l2_bucket *
708 pmap_alloc_l2_bucket(pmap_t pmap, vm_offset_t va)
709 {
710 	struct l2_dtable *l2;
711 	struct l2_bucket *l2b;
712 	u_short l1idx;
713 
714 	l1idx = L1_IDX(va);
715 
716 	PMAP_ASSERT_LOCKED(pmap);
717 	rw_assert(&pvh_global_lock, RA_WLOCKED);
718 	if ((l2 = pmap->pm_l2[L2_IDX(l1idx)]) == NULL) {
719 		/*
720 		 * No mapping at this address, as there is
721 		 * no entry in the L1 table.
722 		 * Need to allocate a new l2_dtable.
723 		 */
724 		PMAP_UNLOCK(pmap);
725 		rw_wunlock(&pvh_global_lock);
726 		if ((l2 = uma_zalloc(l2table_zone, M_NOWAIT)) == NULL) {
727 			rw_wlock(&pvh_global_lock);
728 			PMAP_LOCK(pmap);
729 			return (NULL);
730 		}
731 		rw_wlock(&pvh_global_lock);
732 		PMAP_LOCK(pmap);
733 		if (pmap->pm_l2[L2_IDX(l1idx)] != NULL) {
734 			/*
735 			 * Someone already allocated the l2_dtable while
736 			 * we were doing the same.
737 			 */
738 			uma_zfree(l2table_zone, l2);
739 			l2 = pmap->pm_l2[L2_IDX(l1idx)];
740 		} else {
741 			bzero(l2, sizeof(*l2));
742 			/*
743 			 * Link it into the parent pmap
744 			 */
745 			pmap->pm_l2[L2_IDX(l1idx)] = l2;
746 		}
747 	}
748 
749 	l2b = &l2->l2_bucket[L2_BUCKET(l1idx)];
750 
751 	/*
752 	 * Fetch pointer to the L2 page table associated with the address.
753 	 */
754 	if (l2b->l2b_kva == NULL) {
755 		pt_entry_t *ptep;
756 
757 		/*
758 		 * No L2 page table has been allocated. Chances are, this
759 		 * is because we just allocated the l2_dtable, above.
760 		 */
761 		l2->l2_occupancy++;
762 		PMAP_UNLOCK(pmap);
763 		rw_wunlock(&pvh_global_lock);
764 		ptep = uma_zalloc(l2zone, M_NOWAIT);
765 		rw_wlock(&pvh_global_lock);
766 		PMAP_LOCK(pmap);
767 		if (l2b->l2b_kva != 0) {
768 			/* We lost the race. */
769 			l2->l2_occupancy--;
770 			uma_zfree(l2zone, ptep);
771 			return (l2b);
772 		}
773 		l2b->l2b_phys = vtophys(ptep);
774 		if (ptep == NULL) {
775 			/*
776 			 * Oops, no more L2 page tables available at this
777 			 * time. We may need to deallocate the l2_dtable
778 			 * if we allocated a new one above.
779 			 */
780 			l2->l2_occupancy--;
781 			if (l2->l2_occupancy == 0) {
782 				pmap->pm_l2[L2_IDX(l1idx)] = NULL;
783 				uma_zfree(l2table_zone, l2);
784 			}
785 			return (NULL);
786 		}
787 
788 		l2b->l2b_kva = ptep;
789 		l2b->l2b_l1idx = l1idx;
790 	}
791 
792 	return (l2b);
793 }
794 
795 static PMAP_INLINE void
796 pmap_free_l2_ptp(pt_entry_t *l2)
797 {
798 	uma_zfree(l2zone, l2);
799 }
800 /*
801  * One or more mappings in the specified L2 descriptor table have just been
802  * invalidated.
803  *
804  * Garbage collect the metadata and descriptor table itself if necessary.
805  *
806  * The pmap lock must be acquired when this is called (not necessary
807  * for the kernel pmap).
808  */
809 static void
810 pmap_free_l2_bucket(pmap_t pmap, struct l2_bucket *l2b, u_int count)
811 {
812 	struct l2_dtable *l2;
813 	pd_entry_t *pl1pd, l1pd;
814 	pt_entry_t *ptep;
815 	u_short l1idx;
816 
817 
818 	/*
819 	 * Update the bucket's reference count according to how many
820 	 * PTEs the caller has just invalidated.
821 	 */
822 	l2b->l2b_occupancy -= count;
823 
824 	/*
825 	 * Note:
826 	 *
827 	 * Level 2 page tables allocated to the kernel pmap are never freed
828 	 * as that would require checking all Level 1 page tables and
829 	 * removing any references to the Level 2 page table. See also the
830 	 * comment elsewhere about never freeing bootstrap L2 descriptors.
831 	 *
832 	 * We make do with just invalidating the mapping in the L2 table.
833 	 *
834 	 * This isn't really a big deal in practice and, in fact, leads
835 	 * to a performance win over time as we don't need to continually
836 	 * alloc/free.
837 	 */
838 	if (l2b->l2b_occupancy > 0 || pmap == pmap_kernel())
839 		return;
840 
841 	/*
842 	 * There are no more valid mappings in this level 2 page table.
843 	 * Go ahead and NULL-out the pointer in the bucket, then
844 	 * free the page table.
845 	 */
846 	l1idx = l2b->l2b_l1idx;
847 	ptep = l2b->l2b_kva;
848 	l2b->l2b_kva = NULL;
849 
850 	pl1pd = &pmap->pm_l1->l1_kva[l1idx];
851 
852 	/*
853 	 * If the L1 slot matches the pmap's domain
854 	 * number, then invalidate it.
855 	 */
856 	l1pd = *pl1pd & (L1_TYPE_MASK | L1_C_DOM_MASK);
857 	if (l1pd == (L1_C_DOM(pmap->pm_domain) | L1_TYPE_C)) {
858 		*pl1pd = 0;
859 		PTE_SYNC(pl1pd);
860 		cpu_tlb_flushD_SE((vm_offset_t)ptep);
861 		cpu_cpwait();
862 	}
863 
864 	/*
865 	 * Release the L2 descriptor table back to the pool cache.
866 	 */
867 	pmap_free_l2_ptp(ptep);
868 
869 	/*
870 	 * Update the reference count in the associated l2_dtable
871 	 */
872 	l2 = pmap->pm_l2[L2_IDX(l1idx)];
873 	if (--l2->l2_occupancy > 0)
874 		return;
875 
876 	/*
877 	 * There are no more valid mappings in any of the Level 1
878 	 * slots managed by this l2_dtable. Go ahead and NULL-out
879 	 * the pointer in the parent pmap and free the l2_dtable.
880 	 */
881 	pmap->pm_l2[L2_IDX(l1idx)] = NULL;
882 	uma_zfree(l2table_zone, l2);
883 }
884 
885 /*
886  * Pool cache constructors for L2 descriptor tables, metadata and pmap
887  * structures.
888  */
889 static int
890 pmap_l2ptp_ctor(void *mem, int size, void *arg, int flags)
891 {
892 	struct l2_bucket *l2b;
893 	pt_entry_t *ptep, pte;
894 	vm_offset_t va = (vm_offset_t)mem & ~PAGE_MASK;
895 
896 	/*
897 	 * The mappings for these page tables were initially made using
898 	 * pmap_kenter() by the pool subsystem. Therefore, the cache-
899 	 * mode will not be right for page table mappings. To avoid
900 	 * polluting the pmap_kenter() code with a special case for
901 	 * page tables, we simply fix up the cache-mode here if it's not
902 	 * correct.
903 	 */
904 	l2b = pmap_get_l2_bucket(pmap_kernel(), va);
905 	ptep = &l2b->l2b_kva[l2pte_index(va)];
906 	pte = *ptep;
907 
908 	cpu_idcache_wbinv_range(va, PAGE_SIZE);
909 	pmap_l2cache_wbinv_range(va, pte & L2_S_FRAME, PAGE_SIZE);
910 	if ((pte & L2_S_CACHE_MASK) != pte_l2_s_cache_mode_pt) {
911 		/*
912 		 * Page tables must have the cache-mode set to
913 		 * Write-Thru.
914 		 */
915 		*ptep = (pte & ~L2_S_CACHE_MASK) | pte_l2_s_cache_mode_pt;
916 		PTE_SYNC(ptep);
917 		cpu_tlb_flushD_SE(va);
918 		cpu_cpwait();
919 	}
920 
921 	memset(mem, 0, L2_TABLE_SIZE_REAL);
922 	return (0);
923 }
924 
925 /*
926  * Modify pte bits for all ptes corresponding to the given physical address.
927  * We use `maskbits' rather than `clearbits' because we're always passing
928  * constants and the latter would require an extra inversion at run-time.
929  */
930 static int
931 pmap_clearbit(struct vm_page *m, u_int maskbits)
932 {
933 	struct l2_bucket *l2b;
934 	struct pv_entry *pv, *pve, *next_pv;
935 	struct md_page *pvh;
936 	pd_entry_t *pl1pd;
937 	pt_entry_t *ptep, npte, opte;
938 	pmap_t pmap;
939 	vm_offset_t va;
940 	u_int oflags;
941 	int count = 0;
942 
943 	rw_wlock(&pvh_global_lock);
944 	if ((m->flags & PG_FICTITIOUS) != 0)
945 		goto small_mappings;
946 
947 	pvh = pa_to_pvh(VM_PAGE_TO_PHYS(m));
948 	TAILQ_FOREACH_SAFE(pv, &pvh->pv_list, pv_list, next_pv) {
949 		va = pv->pv_va;
950 		pmap = PV_PMAP(pv);
951 		PMAP_LOCK(pmap);
952 		pl1pd = &pmap->pm_l1->l1_kva[L1_IDX(va)];
953 		KASSERT((*pl1pd & L1_TYPE_MASK) == L1_S_PROTO,
954 		    ("pmap_clearbit: valid section mapping expected"));
955 		if ((maskbits & PVF_WRITE) && (pv->pv_flags & PVF_WRITE))
956 			(void)pmap_demote_section(pmap, va);
957 		else if ((maskbits & PVF_REF) && L1_S_REFERENCED(*pl1pd)) {
958 			if (pmap_demote_section(pmap, va)) {
959 				if ((pv->pv_flags & PVF_WIRED) == 0) {
960 					/*
961 					 * Remove the mapping to a single page
962 					 * so that a subsequent access may
963 					 * repromote. Since the underlying
964 					 * l2_bucket is fully populated, this
965 					 * removal never frees an entire
966 					 * l2_bucket.
967 					 */
968 					va += (VM_PAGE_TO_PHYS(m) &
969 					    L1_S_OFFSET);
970 					l2b = pmap_get_l2_bucket(pmap, va);
971 					KASSERT(l2b != NULL,
972 					    ("pmap_clearbit: no l2 bucket for "
973 					     "va 0x%#x, pmap 0x%p", va, pmap));
974 					ptep = &l2b->l2b_kva[l2pte_index(va)];
975 					*ptep = 0;
976 					PTE_SYNC(ptep);
977 					pmap_free_l2_bucket(pmap, l2b, 1);
978 					pve = pmap_remove_pv(m, pmap, va);
979 					KASSERT(pve != NULL, ("pmap_clearbit: "
980 					    "no PV entry for managed mapping"));
981 					pmap_free_pv_entry(pmap, pve);
982 
983 				}
984 			}
985 		} else if ((maskbits & PVF_MOD) && L1_S_WRITABLE(*pl1pd)) {
986 			if (pmap_demote_section(pmap, va)) {
987 				if ((pv->pv_flags & PVF_WIRED) == 0) {
988 					/*
989 					 * Write protect the mapping to a
990 					 * single page so that a subsequent
991 					 * write access may repromote.
992 					 */
993 					va += (VM_PAGE_TO_PHYS(m) &
994 					    L1_S_OFFSET);
995 					l2b = pmap_get_l2_bucket(pmap, va);
996 					KASSERT(l2b != NULL,
997 					    ("pmap_clearbit: no l2 bucket for "
998 					     "va 0x%#x, pmap 0x%p", va, pmap));
999 					ptep = &l2b->l2b_kva[l2pte_index(va)];
1000 					if ((*ptep & L2_S_PROTO) != 0) {
1001 						pve = pmap_find_pv(&m->md,
1002 						    pmap, va);
1003 						KASSERT(pve != NULL,
1004 						    ("pmap_clearbit: no PV "
1005 						    "entry for managed mapping"));
1006 						pve->pv_flags &= ~PVF_WRITE;
1007 						*ptep |= L2_APX;
1008 						PTE_SYNC(ptep);
1009 					}
1010 				}
1011 			}
1012 		}
1013 		PMAP_UNLOCK(pmap);
1014 	}
1015 
1016 small_mappings:
1017 	if (TAILQ_EMPTY(&m->md.pv_list)) {
1018 		rw_wunlock(&pvh_global_lock);
1019 		return (0);
1020 	}
1021 
1022 	/*
1023 	 * Loop over all current mappings setting/clearing as appropos
1024 	 */
1025 	TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
1026 		va = pv->pv_va;
1027 		pmap = PV_PMAP(pv);
1028 		oflags = pv->pv_flags;
1029 		pv->pv_flags &= ~maskbits;
1030 
1031 		PMAP_LOCK(pmap);
1032 
1033 		l2b = pmap_get_l2_bucket(pmap, va);
1034 		KASSERT(l2b != NULL, ("pmap_clearbit: no l2 bucket for "
1035 		    "va 0x%#x, pmap 0x%p", va, pmap));
1036 
1037 		ptep = &l2b->l2b_kva[l2pte_index(va)];
1038 		npte = opte = *ptep;
1039 
1040 		if (maskbits & (PVF_WRITE | PVF_MOD)) {
1041 			/* make the pte read only */
1042 			npte |= L2_APX;
1043 		}
1044 
1045 		if (maskbits & PVF_REF) {
1046 			/*
1047 			 * Clear referenced flag in PTE so that we
1048 			 * will take a flag fault the next time the mapping
1049 			 * is referenced.
1050 			 */
1051 			npte &= ~L2_S_REF;
1052 		}
1053 
1054 		CTR4(KTR_PMAP,"clearbit: pmap:%p bits:%x pte:%x->%x",
1055 		    pmap, maskbits, opte, npte);
1056 		if (npte != opte) {
1057 			count++;
1058 			*ptep = npte;
1059 			PTE_SYNC(ptep);
1060 			/* Flush the TLB entry if a current pmap. */
1061 			if (PTE_BEEN_EXECD(opte))
1062 				cpu_tlb_flushID_SE(pv->pv_va);
1063 			else if (PTE_BEEN_REFD(opte))
1064 				cpu_tlb_flushD_SE(pv->pv_va);
1065 			cpu_cpwait();
1066 		}
1067 
1068 		PMAP_UNLOCK(pmap);
1069 
1070 	}
1071 
1072 	if (maskbits & PVF_WRITE)
1073 		vm_page_aflag_clear(m, PGA_WRITEABLE);
1074 	rw_wunlock(&pvh_global_lock);
1075 	return (count);
1076 }
1077 
1078 /*
1079  * main pv_entry manipulation functions:
1080  *   pmap_enter_pv: enter a mapping onto a vm_page list
1081  *   pmap_remove_pv: remove a mappiing from a vm_page list
1082  *
1083  * NOTE: pmap_enter_pv expects to lock the pvh itself
1084  *       pmap_remove_pv expects the caller to lock the pvh before calling
1085  */
1086 
1087 /*
1088  * pmap_enter_pv: enter a mapping onto a vm_page's PV list
1089  *
1090  * => caller should hold the proper lock on pvh_global_lock
1091  * => caller should have pmap locked
1092  * => we will (someday) gain the lock on the vm_page's PV list
1093  * => caller should adjust ptp's wire_count before calling
1094  * => caller should not adjust pmap's wire_count
1095  */
1096 static void
1097 pmap_enter_pv(struct vm_page *m, struct pv_entry *pve, pmap_t pmap,
1098     vm_offset_t va, u_int flags)
1099 {
1100 
1101 	rw_assert(&pvh_global_lock, RA_WLOCKED);
1102 
1103 	PMAP_ASSERT_LOCKED(pmap);
1104 	pve->pv_va = va;
1105 	pve->pv_flags = flags;
1106 
1107 	TAILQ_INSERT_HEAD(&m->md.pv_list, pve, pv_list);
1108 	if (pve->pv_flags & PVF_WIRED)
1109 		++pmap->pm_stats.wired_count;
1110 }
1111 
1112 /*
1113  *
1114  * pmap_find_pv: Find a pv entry
1115  *
1116  * => caller should hold lock on vm_page
1117  */
1118 static PMAP_INLINE struct pv_entry *
1119 pmap_find_pv(struct md_page *md, pmap_t pmap, vm_offset_t va)
1120 {
1121 	struct pv_entry *pv;
1122 
1123 	rw_assert(&pvh_global_lock, RA_WLOCKED);
1124 	TAILQ_FOREACH(pv, &md->pv_list, pv_list)
1125 		if (pmap == PV_PMAP(pv) && va == pv->pv_va)
1126 			break;
1127 
1128 	return (pv);
1129 }
1130 
1131 /*
1132  * vector_page_setprot:
1133  *
1134  *	Manipulate the protection of the vector page.
1135  */
1136 void
1137 vector_page_setprot(int prot)
1138 {
1139 	struct l2_bucket *l2b;
1140 	pt_entry_t *ptep;
1141 
1142 	l2b = pmap_get_l2_bucket(pmap_kernel(), vector_page);
1143 
1144 	ptep = &l2b->l2b_kva[l2pte_index(vector_page)];
1145 	/*
1146 	 * Set referenced flag.
1147 	 * Vectors' page is always desired
1148 	 * to be allowed to reside in TLB.
1149 	 */
1150 	*ptep |= L2_S_REF;
1151 
1152 	pmap_set_prot(ptep, prot|VM_PROT_EXECUTE, 0);
1153 	PTE_SYNC(ptep);
1154 	cpu_tlb_flushID_SE(vector_page);
1155 	cpu_cpwait();
1156 }
1157 
1158 static void
1159 pmap_set_prot(pt_entry_t *ptep, vm_prot_t prot, uint8_t user)
1160 {
1161 
1162 	*ptep &= ~(L2_S_PROT_MASK | L2_XN);
1163 
1164 	if (!(prot & VM_PROT_EXECUTE))
1165 		*ptep |= L2_XN;
1166 
1167 	/* Set defaults first - kernel read access */
1168 	*ptep |= L2_APX;
1169 	*ptep |= L2_S_PROT_R;
1170 	/* Now tune APs as desired */
1171 	if (user)
1172 		*ptep |= L2_S_PROT_U;
1173 
1174 	if (prot & VM_PROT_WRITE)
1175 		*ptep &= ~(L2_APX);
1176 }
1177 
1178 /*
1179  * pmap_remove_pv: try to remove a mapping from a pv_list
1180  *
1181  * => caller should hold proper lock on pmap_main_lock
1182  * => pmap should be locked
1183  * => caller should hold lock on vm_page [so that attrs can be adjusted]
1184  * => caller should adjust ptp's wire_count and free PTP if needed
1185  * => caller should NOT adjust pmap's wire_count
1186  * => we return the removed pve
1187  */
1188 static struct pv_entry *
1189 pmap_remove_pv(struct vm_page *m, pmap_t pmap, vm_offset_t va)
1190 {
1191 	struct pv_entry *pve;
1192 
1193 	rw_assert(&pvh_global_lock, RA_WLOCKED);
1194 	PMAP_ASSERT_LOCKED(pmap);
1195 
1196 	pve = pmap_find_pv(&m->md, pmap, va);	/* find corresponding pve */
1197 	if (pve != NULL) {
1198 		TAILQ_REMOVE(&m->md.pv_list, pve, pv_list);
1199 		if (pve->pv_flags & PVF_WIRED)
1200 			--pmap->pm_stats.wired_count;
1201 	}
1202 	if (TAILQ_EMPTY(&m->md.pv_list))
1203 		vm_page_aflag_clear(m, PGA_WRITEABLE);
1204 
1205 	return(pve);				/* return removed pve */
1206 }
1207 
1208 /*
1209  *
1210  * pmap_modify_pv: Update pv flags
1211  *
1212  * => caller should hold lock on vm_page [so that attrs can be adjusted]
1213  * => caller should NOT adjust pmap's wire_count
1214  * => we return the old flags
1215  *
1216  * Modify a physical-virtual mapping in the pv table
1217  */
1218 static u_int
1219 pmap_modify_pv(struct vm_page *m, pmap_t pmap, vm_offset_t va,
1220     u_int clr_mask, u_int set_mask)
1221 {
1222 	struct pv_entry *npv;
1223 	u_int flags, oflags;
1224 
1225 	PMAP_ASSERT_LOCKED(pmap);
1226 	rw_assert(&pvh_global_lock, RA_WLOCKED);
1227 	if ((npv = pmap_find_pv(&m->md, pmap, va)) == NULL)
1228 		return (0);
1229 
1230 	/*
1231 	 * There is at least one VA mapping this page.
1232 	 */
1233 	oflags = npv->pv_flags;
1234 	npv->pv_flags = flags = (oflags & ~clr_mask) | set_mask;
1235 
1236 	if ((flags ^ oflags) & PVF_WIRED) {
1237 		if (flags & PVF_WIRED)
1238 			++pmap->pm_stats.wired_count;
1239 		else
1240 			--pmap->pm_stats.wired_count;
1241 	}
1242 
1243 	return (oflags);
1244 }
1245 
1246 /* Function to set the debug level of the pmap code */
1247 #ifdef PMAP_DEBUG
1248 void
1249 pmap_debug(int level)
1250 {
1251 	pmap_debug_level = level;
1252 	dprintf("pmap_debug: level=%d\n", pmap_debug_level);
1253 }
1254 #endif  /* PMAP_DEBUG */
1255 
1256 void
1257 pmap_pinit0(struct pmap *pmap)
1258 {
1259 	PDEBUG(1, printf("pmap_pinit0: pmap = %08x\n", (u_int32_t) pmap));
1260 
1261 	bcopy(kernel_pmap, pmap, sizeof(*pmap));
1262 	bzero(&pmap->pm_mtx, sizeof(pmap->pm_mtx));
1263 	PMAP_LOCK_INIT(pmap);
1264 	TAILQ_INIT(&pmap->pm_pvchunk);
1265 }
1266 
1267 /*
1268  *	Initialize a vm_page's machine-dependent fields.
1269  */
1270 void
1271 pmap_page_init(vm_page_t m)
1272 {
1273 
1274 	TAILQ_INIT(&m->md.pv_list);
1275 	m->md.pv_memattr = VM_MEMATTR_DEFAULT;
1276 }
1277 
1278 static vm_offset_t
1279 pmap_ptelist_alloc(vm_offset_t *head)
1280 {
1281 	pt_entry_t *pte;
1282 	vm_offset_t va;
1283 
1284 	va = *head;
1285 	if (va == 0)
1286 		return (va);	/* Out of memory */
1287 	pte = vtopte(va);
1288 	*head = *pte;
1289 	if ((*head & L2_TYPE_MASK) != L2_TYPE_INV)
1290 		panic("%s: va is not L2_TYPE_INV!", __func__);
1291 	*pte = 0;
1292 	return (va);
1293 }
1294 
1295 static void
1296 pmap_ptelist_free(vm_offset_t *head, vm_offset_t va)
1297 {
1298 	pt_entry_t *pte;
1299 
1300 	if ((va & L2_TYPE_MASK) != L2_TYPE_INV)
1301 		panic("%s: freeing va that is not L2_TYPE INV!", __func__);
1302 	pte = vtopte(va);
1303 	*pte = *head;		/* virtual! L2_TYPE is L2_TYPE_INV though */
1304 	*head = va;
1305 }
1306 
1307 static void
1308 pmap_ptelist_init(vm_offset_t *head, void *base, int npages)
1309 {
1310 	int i;
1311 	vm_offset_t va;
1312 
1313 	*head = 0;
1314 	for (i = npages - 1; i >= 0; i--) {
1315 		va = (vm_offset_t)base + i * PAGE_SIZE;
1316 		pmap_ptelist_free(head, va);
1317 	}
1318 }
1319 
1320 /*
1321  *      Initialize the pmap module.
1322  *      Called by vm_init, to initialize any structures that the pmap
1323  *      system needs to map virtual memory.
1324  */
1325 void
1326 pmap_init(void)
1327 {
1328 	vm_size_t s;
1329 	int i, pv_npg;
1330 
1331 	l2zone = uma_zcreate("L2 Table", L2_TABLE_SIZE_REAL, pmap_l2ptp_ctor,
1332 	    NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_VM | UMA_ZONE_NOFREE);
1333 	l2table_zone = uma_zcreate("L2 Table", sizeof(struct l2_dtable), NULL,
1334 	    NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_VM | UMA_ZONE_NOFREE);
1335 
1336 	/*
1337 	 * Are large page mappings supported and enabled?
1338 	 */
1339 	TUNABLE_INT_FETCH("vm.pmap.sp_enabled", &sp_enabled);
1340 	if (sp_enabled) {
1341 		KASSERT(MAXPAGESIZES > 1 && pagesizes[1] == 0,
1342 		    ("pmap_init: can't assign to pagesizes[1]"));
1343 		pagesizes[1] = NBPDR;
1344 	}
1345 
1346 	/*
1347 	 * Calculate the size of the pv head table for superpages.
1348 	 * Handle the possibility that "vm_phys_segs[...].end" is zero.
1349 	 */
1350 	pv_npg = trunc_1mpage(vm_phys_segs[vm_phys_nsegs - 1].end -
1351 	    PAGE_SIZE) / NBPDR + 1;
1352 
1353 	/*
1354 	 * Allocate memory for the pv head table for superpages.
1355 	 */
1356 	s = (vm_size_t)(pv_npg * sizeof(struct md_page));
1357 	s = round_page(s);
1358 	pv_table = (struct md_page *)kmem_malloc(kernel_arena, s,
1359 	    M_WAITOK | M_ZERO);
1360 	for (i = 0; i < pv_npg; i++)
1361 		TAILQ_INIT(&pv_table[i].pv_list);
1362 
1363 	/*
1364 	 * Initialize the address space for the pv chunks.
1365 	 */
1366 
1367 	TUNABLE_INT_FETCH("vm.pmap.shpgperproc", &shpgperproc);
1368 	pv_entry_max = shpgperproc * maxproc + vm_cnt.v_page_count;
1369 	TUNABLE_INT_FETCH("vm.pmap.pv_entries", &pv_entry_max);
1370 	pv_entry_max = roundup(pv_entry_max, _NPCPV);
1371 	pv_entry_high_water = 9 * (pv_entry_max / 10);
1372 
1373 	pv_maxchunks = MAX(pv_entry_max / _NPCPV, maxproc);
1374 	pv_chunkbase = (struct pv_chunk *)kva_alloc(PAGE_SIZE * pv_maxchunks);
1375 
1376 	if (pv_chunkbase == NULL)
1377 		panic("pmap_init: not enough kvm for pv chunks");
1378 
1379 	pmap_ptelist_init(&pv_vafree, pv_chunkbase, pv_maxchunks);
1380 
1381 	/*
1382 	 * Now it is safe to enable pv_table recording.
1383 	 */
1384 	PDEBUG(1, printf("pmap_init: done!\n"));
1385 }
1386 
1387 SYSCTL_INT(_vm_pmap, OID_AUTO, pv_entry_max, CTLFLAG_RD, &pv_entry_max, 0,
1388 	"Max number of PV entries");
1389 SYSCTL_INT(_vm_pmap, OID_AUTO, shpgperproc, CTLFLAG_RD, &shpgperproc, 0,
1390 	"Page share factor per proc");
1391 
1392 static SYSCTL_NODE(_vm_pmap, OID_AUTO, section, CTLFLAG_RD, 0,
1393     "1MB page mapping counters");
1394 
1395 static u_long pmap_section_demotions;
1396 SYSCTL_ULONG(_vm_pmap_section, OID_AUTO, demotions, CTLFLAG_RD,
1397     &pmap_section_demotions, 0, "1MB page demotions");
1398 
1399 static u_long pmap_section_mappings;
1400 SYSCTL_ULONG(_vm_pmap_section, OID_AUTO, mappings, CTLFLAG_RD,
1401     &pmap_section_mappings, 0, "1MB page mappings");
1402 
1403 static u_long pmap_section_p_failures;
1404 SYSCTL_ULONG(_vm_pmap_section, OID_AUTO, p_failures, CTLFLAG_RD,
1405     &pmap_section_p_failures, 0, "1MB page promotion failures");
1406 
1407 static u_long pmap_section_promotions;
1408 SYSCTL_ULONG(_vm_pmap_section, OID_AUTO, promotions, CTLFLAG_RD,
1409     &pmap_section_promotions, 0, "1MB page promotions");
1410 
1411 int
1412 pmap_fault_fixup(pmap_t pmap, vm_offset_t va, vm_prot_t ftype, int user)
1413 {
1414 	struct l2_dtable *l2;
1415 	struct l2_bucket *l2b;
1416 	pd_entry_t *pl1pd, l1pd;
1417 	pt_entry_t *ptep, pte;
1418 	vm_paddr_t pa;
1419 	u_int l1idx;
1420 	int rv = 0;
1421 
1422 	l1idx = L1_IDX(va);
1423 	rw_wlock(&pvh_global_lock);
1424 	PMAP_LOCK(pmap);
1425 	/*
1426 	 * Check and possibly fix-up L1 section mapping
1427 	 * only when superpage mappings are enabled to speed up.
1428 	 */
1429 	if (sp_enabled) {
1430 		pl1pd = &pmap->pm_l1->l1_kva[l1idx];
1431 		l1pd = *pl1pd;
1432 		if ((l1pd & L1_TYPE_MASK) == L1_S_PROTO) {
1433 			/* Catch an access to the vectors section */
1434 			if (l1idx == L1_IDX(vector_page))
1435 				goto out;
1436 			/*
1437 			 * Stay away from the kernel mappings.
1438 			 * None of them should fault from L1 entry.
1439 			 */
1440 			if (pmap == pmap_kernel())
1441 				goto out;
1442 			/*
1443 			 * Catch a forbidden userland access
1444 			 */
1445 			if (user && !(l1pd & L1_S_PROT_U))
1446 				goto out;
1447 			/*
1448 			 * Superpage is always either mapped read only
1449 			 * or it is modified and permitted to be written
1450 			 * by default. Therefore, process only reference
1451 			 * flag fault and demote page in case of write fault.
1452 			 */
1453 			if ((ftype & VM_PROT_WRITE) && !L1_S_WRITABLE(l1pd) &&
1454 			    L1_S_REFERENCED(l1pd)) {
1455 				(void)pmap_demote_section(pmap, va);
1456 				goto out;
1457 			} else if (!L1_S_REFERENCED(l1pd)) {
1458 				/* Mark the page "referenced" */
1459 				*pl1pd = l1pd | L1_S_REF;
1460 				PTE_SYNC(pl1pd);
1461 				goto l1_section_out;
1462 			} else
1463 				goto out;
1464 		}
1465 	}
1466 	/*
1467 	 * If there is no l2_dtable for this address, then the process
1468 	 * has no business accessing it.
1469 	 *
1470 	 * Note: This will catch userland processes trying to access
1471 	 * kernel addresses.
1472 	 */
1473 	l2 = pmap->pm_l2[L2_IDX(l1idx)];
1474 	if (l2 == NULL)
1475 		goto out;
1476 
1477 	/*
1478 	 * Likewise if there is no L2 descriptor table
1479 	 */
1480 	l2b = &l2->l2_bucket[L2_BUCKET(l1idx)];
1481 	if (l2b->l2b_kva == NULL)
1482 		goto out;
1483 
1484 	/*
1485 	 * Check the PTE itself.
1486 	 */
1487 	ptep = &l2b->l2b_kva[l2pte_index(va)];
1488 	pte = *ptep;
1489 	if (pte == 0)
1490 		goto out;
1491 
1492 	/*
1493 	 * Catch a userland access to the vector page mapped at 0x0
1494 	 */
1495 	if (user && !(pte & L2_S_PROT_U))
1496 		goto out;
1497 	if (va == vector_page)
1498 		goto out;
1499 
1500 	pa = l2pte_pa(pte);
1501 	CTR5(KTR_PMAP, "pmap_fault_fix: pmap:%p va:%x pte:0x%x ftype:%x user:%x",
1502 	    pmap, va, pte, ftype, user);
1503 	if ((ftype & VM_PROT_WRITE) && !(L2_S_WRITABLE(pte)) &&
1504 	    L2_S_REFERENCED(pte)) {
1505 		/*
1506 		 * This looks like a good candidate for "page modified"
1507 		 * emulation...
1508 		 */
1509 		struct pv_entry *pv;
1510 		struct vm_page *m;
1511 
1512 		/* Extract the physical address of the page */
1513 		if ((m = PHYS_TO_VM_PAGE(pa)) == NULL) {
1514 			goto out;
1515 		}
1516 		/* Get the current flags for this page. */
1517 
1518 		pv = pmap_find_pv(&m->md, pmap, va);
1519 		if (pv == NULL) {
1520 			goto out;
1521 		}
1522 
1523 		/*
1524 		 * Do the flags say this page is writable? If not then it
1525 		 * is a genuine write fault. If yes then the write fault is
1526 		 * our fault as we did not reflect the write access in the
1527 		 * PTE. Now we know a write has occurred we can correct this
1528 		 * and also set the modified bit
1529 		 */
1530 		if ((pv->pv_flags & PVF_WRITE) == 0) {
1531 			goto out;
1532 		}
1533 
1534 		vm_page_dirty(m);
1535 
1536 		/* Re-enable write permissions for the page */
1537 		*ptep = (pte & ~L2_APX);
1538 		PTE_SYNC(ptep);
1539 		rv = 1;
1540 		CTR1(KTR_PMAP, "pmap_fault_fix: new pte:0x%x", *ptep);
1541 	} else if (!L2_S_REFERENCED(pte)) {
1542 		/*
1543 		 * This looks like a good candidate for "page referenced"
1544 		 * emulation.
1545 		 */
1546 		struct pv_entry *pv;
1547 		struct vm_page *m;
1548 
1549 		/* Extract the physical address of the page */
1550 		if ((m = PHYS_TO_VM_PAGE(pa)) == NULL)
1551 			goto out;
1552 		/* Get the current flags for this page. */
1553 		pv = pmap_find_pv(&m->md, pmap, va);
1554 		if (pv == NULL)
1555 			goto out;
1556 
1557 		vm_page_aflag_set(m, PGA_REFERENCED);
1558 
1559 		/* Mark the page "referenced" */
1560 		*ptep = pte | L2_S_REF;
1561 		PTE_SYNC(ptep);
1562 		rv = 1;
1563 		CTR1(KTR_PMAP, "pmap_fault_fix: new pte:0x%x", *ptep);
1564 	}
1565 
1566 	/*
1567 	 * We know there is a valid mapping here, so simply
1568 	 * fix up the L1 if necessary.
1569 	 */
1570 	pl1pd = &pmap->pm_l1->l1_kva[l1idx];
1571 	l1pd = l2b->l2b_phys | L1_C_DOM(pmap->pm_domain) | L1_C_PROTO;
1572 	if (*pl1pd != l1pd) {
1573 		*pl1pd = l1pd;
1574 		PTE_SYNC(pl1pd);
1575 		rv = 1;
1576 	}
1577 
1578 #ifdef DEBUG
1579 	/*
1580 	 * If 'rv == 0' at this point, it generally indicates that there is a
1581 	 * stale TLB entry for the faulting address. This happens when two or
1582 	 * more processes are sharing an L1. Since we don't flush the TLB on
1583 	 * a context switch between such processes, we can take domain faults
1584 	 * for mappings which exist at the same VA in both processes. EVEN IF
1585 	 * WE'VE RECENTLY FIXED UP THE CORRESPONDING L1 in pmap_enter(), for
1586 	 * example.
1587 	 *
1588 	 * This is extremely likely to happen if pmap_enter() updated the L1
1589 	 * entry for a recently entered mapping. In this case, the TLB is
1590 	 * flushed for the new mapping, but there may still be TLB entries for
1591 	 * other mappings belonging to other processes in the 1MB range
1592 	 * covered by the L1 entry.
1593 	 *
1594 	 * Since 'rv == 0', we know that the L1 already contains the correct
1595 	 * value, so the fault must be due to a stale TLB entry.
1596 	 *
1597 	 * Since we always need to flush the TLB anyway in the case where we
1598 	 * fixed up the L1, or frobbed the L2 PTE, we effectively deal with
1599 	 * stale TLB entries dynamically.
1600 	 *
1601 	 * However, the above condition can ONLY happen if the current L1 is
1602 	 * being shared. If it happens when the L1 is unshared, it indicates
1603 	 * that other parts of the pmap are not doing their job WRT managing
1604 	 * the TLB.
1605 	 */
1606 	if (rv == 0 && pmap->pm_l1->l1_domain_use_count == 1) {
1607 		printf("fixup: pmap %p, va 0x%08x, ftype %d - nothing to do!\n",
1608 		    pmap, va, ftype);
1609 		printf("fixup: l2 %p, l2b %p, ptep %p, pl1pd %p\n",
1610 		    l2, l2b, ptep, pl1pd);
1611 		printf("fixup: pte 0x%x, l1pd 0x%x, last code 0x%x\n",
1612 		    pte, l1pd, last_fault_code);
1613 #ifdef DDB
1614 		Debugger();
1615 #endif
1616 	}
1617 #endif
1618 
1619 l1_section_out:
1620 	cpu_tlb_flushID_SE(va);
1621 	cpu_cpwait();
1622 
1623 	rv = 1;
1624 
1625 out:
1626 	rw_wunlock(&pvh_global_lock);
1627 	PMAP_UNLOCK(pmap);
1628 	return (rv);
1629 }
1630 
1631 void
1632 pmap_postinit(void)
1633 {
1634 	struct l2_bucket *l2b;
1635 	struct l1_ttable *l1;
1636 	pd_entry_t *pl1pt;
1637 	pt_entry_t *ptep, pte;
1638 	vm_offset_t va, eva;
1639 	u_int loop, needed;
1640 
1641 	needed = (maxproc / PMAP_DOMAINS) + ((maxproc % PMAP_DOMAINS) ? 1 : 0);
1642 	needed -= 1;
1643 	l1 = malloc(sizeof(*l1) * needed, M_VMPMAP, M_WAITOK);
1644 
1645 	for (loop = 0; loop < needed; loop++, l1++) {
1646 		/* Allocate a L1 page table */
1647 		va = (vm_offset_t)contigmalloc(L1_TABLE_SIZE, M_VMPMAP, 0, 0x0,
1648 		    0xffffffff, L1_TABLE_SIZE, 0);
1649 
1650 		if (va == 0)
1651 			panic("Cannot allocate L1 KVM");
1652 
1653 		eva = va + L1_TABLE_SIZE;
1654 		pl1pt = (pd_entry_t *)va;
1655 
1656 		while (va < eva) {
1657 				l2b = pmap_get_l2_bucket(pmap_kernel(), va);
1658 				ptep = &l2b->l2b_kva[l2pte_index(va)];
1659 				pte = *ptep;
1660 				pte = (pte & ~L2_S_CACHE_MASK) | pte_l2_s_cache_mode_pt;
1661 				*ptep = pte;
1662 				PTE_SYNC(ptep);
1663 				cpu_tlb_flushID_SE(va);
1664 				cpu_cpwait();
1665 				va += PAGE_SIZE;
1666 		}
1667 		pmap_init_l1(l1, pl1pt);
1668 	}
1669 #ifdef DEBUG
1670 	printf("pmap_postinit: Allocated %d static L1 descriptor tables\n",
1671 	    needed);
1672 #endif
1673 }
1674 
1675 /*
1676  * This is used to stuff certain critical values into the PCB where they
1677  * can be accessed quickly from cpu_switch() et al.
1678  */
1679 void
1680 pmap_set_pcb_pagedir(pmap_t pmap, struct pcb *pcb)
1681 {
1682 	struct l2_bucket *l2b;
1683 
1684 	pcb->pcb_pagedir = pmap->pm_l1->l1_physaddr;
1685 	pcb->pcb_dacr = (DOMAIN_CLIENT << (PMAP_DOMAIN_KERNEL * 2)) |
1686 	    (DOMAIN_CLIENT << (pmap->pm_domain * 2));
1687 
1688 	if (vector_page < KERNBASE) {
1689 		pcb->pcb_pl1vec = &pmap->pm_l1->l1_kva[L1_IDX(vector_page)];
1690 		l2b = pmap_get_l2_bucket(pmap, vector_page);
1691 		pcb->pcb_l1vec = l2b->l2b_phys | L1_C_PROTO |
1692 		    L1_C_DOM(pmap->pm_domain) | L1_C_DOM(PMAP_DOMAIN_KERNEL);
1693 	} else
1694 		pcb->pcb_pl1vec = NULL;
1695 }
1696 
1697 void
1698 pmap_activate(struct thread *td)
1699 {
1700 	pmap_t pmap;
1701 	struct pcb *pcb;
1702 
1703 	pmap = vmspace_pmap(td->td_proc->p_vmspace);
1704 	pcb = td->td_pcb;
1705 
1706 	critical_enter();
1707 	pmap_set_pcb_pagedir(pmap, pcb);
1708 
1709 	if (td == curthread) {
1710 		u_int cur_dacr, cur_ttb;
1711 
1712 		__asm __volatile("mrc p15, 0, %0, c2, c0, 0" : "=r"(cur_ttb));
1713 		__asm __volatile("mrc p15, 0, %0, c3, c0, 0" : "=r"(cur_dacr));
1714 
1715 		cur_ttb &= ~(L1_TABLE_SIZE - 1);
1716 
1717 		if (cur_ttb == (u_int)pcb->pcb_pagedir &&
1718 		    cur_dacr == pcb->pcb_dacr) {
1719 			/*
1720 			 * No need to switch address spaces.
1721 			 */
1722 			critical_exit();
1723 			return;
1724 		}
1725 
1726 
1727 		/*
1728 		 * We MUST, I repeat, MUST fix up the L1 entry corresponding
1729 		 * to 'vector_page' in the incoming L1 table before switching
1730 		 * to it otherwise subsequent interrupts/exceptions (including
1731 		 * domain faults!) will jump into hyperspace.
1732 		 */
1733 		if (pcb->pcb_pl1vec) {
1734 			*pcb->pcb_pl1vec = pcb->pcb_l1vec;
1735 		}
1736 
1737 		cpu_domains(pcb->pcb_dacr);
1738 		cpu_setttb(pcb->pcb_pagedir);
1739 	}
1740 	critical_exit();
1741 }
1742 
1743 static int
1744 pmap_set_pt_cache_mode(pd_entry_t *kl1, vm_offset_t va)
1745 {
1746 	pd_entry_t *pdep, pde;
1747 	pt_entry_t *ptep, pte;
1748 	vm_offset_t pa;
1749 	int rv = 0;
1750 
1751 	/*
1752 	 * Make sure the descriptor itself has the correct cache mode
1753 	 */
1754 	pdep = &kl1[L1_IDX(va)];
1755 	pde = *pdep;
1756 
1757 	if (l1pte_section_p(pde)) {
1758 		if ((pde & L1_S_CACHE_MASK) != pte_l1_s_cache_mode_pt) {
1759 			*pdep = (pde & ~L1_S_CACHE_MASK) |
1760 			    pte_l1_s_cache_mode_pt;
1761 			PTE_SYNC(pdep);
1762 			rv = 1;
1763 		}
1764 	} else {
1765 		pa = (vm_paddr_t)(pde & L1_C_ADDR_MASK);
1766 		ptep = (pt_entry_t *)kernel_pt_lookup(pa);
1767 		if (ptep == NULL)
1768 			panic("pmap_bootstrap: No L2 for L2 @ va %p\n", ptep);
1769 
1770 		ptep = &ptep[l2pte_index(va)];
1771 		pte = *ptep;
1772 		if ((pte & L2_S_CACHE_MASK) != pte_l2_s_cache_mode_pt) {
1773 			*ptep = (pte & ~L2_S_CACHE_MASK) |
1774 			    pte_l2_s_cache_mode_pt;
1775 			PTE_SYNC(ptep);
1776 			rv = 1;
1777 		}
1778 	}
1779 
1780 	return (rv);
1781 }
1782 
1783 static void
1784 pmap_alloc_specials(vm_offset_t *availp, int pages, vm_offset_t *vap,
1785     pt_entry_t **ptep)
1786 {
1787 	vm_offset_t va = *availp;
1788 	struct l2_bucket *l2b;
1789 
1790 	if (ptep) {
1791 		l2b = pmap_get_l2_bucket(pmap_kernel(), va);
1792 		if (l2b == NULL)
1793 			panic("pmap_alloc_specials: no l2b for 0x%x", va);
1794 
1795 		*ptep = &l2b->l2b_kva[l2pte_index(va)];
1796 	}
1797 
1798 	*vap = va;
1799 	*availp = va + (PAGE_SIZE * pages);
1800 }
1801 
1802 /*
1803  *	Bootstrap the system enough to run with virtual memory.
1804  *
1805  *	On the arm this is called after mapping has already been enabled
1806  *	and just syncs the pmap module with what has already been done.
1807  *	[We can't call it easily with mapping off since the kernel is not
1808  *	mapped with PA == VA, hence we would have to relocate every address
1809  *	from the linked base (virtual) address "KERNBASE" to the actual
1810  *	(physical) address starting relative to 0]
1811  */
1812 #define PMAP_STATIC_L2_SIZE 16
1813 
1814 void
1815 pmap_bootstrap(vm_offset_t firstaddr, struct pv_addr *l1pt)
1816 {
1817 	static struct l1_ttable static_l1;
1818 	static struct l2_dtable static_l2[PMAP_STATIC_L2_SIZE];
1819 	struct l1_ttable *l1 = &static_l1;
1820 	struct l2_dtable *l2;
1821 	struct l2_bucket *l2b;
1822 	struct czpages *czp;
1823 	pd_entry_t pde;
1824 	pd_entry_t *kernel_l1pt = (pd_entry_t *)l1pt->pv_va;
1825 	pt_entry_t *ptep;
1826 	vm_paddr_t pa;
1827 	vm_offset_t va;
1828 	vm_size_t size;
1829 	int i, l1idx, l2idx, l2next = 0;
1830 
1831 	PDEBUG(1, printf("firstaddr = %08x, lastaddr = %08x\n",
1832 	    firstaddr, vm_max_kernel_address));
1833 
1834 	virtual_avail = firstaddr;
1835 	kernel_pmap->pm_l1 = l1;
1836 	kernel_l1pa = l1pt->pv_pa;
1837 
1838 	/*
1839 	 * Scan the L1 translation table created by initarm() and create
1840 	 * the required metadata for all valid mappings found in it.
1841 	 */
1842 	for (l1idx = 0; l1idx < (L1_TABLE_SIZE / sizeof(pd_entry_t)); l1idx++) {
1843 		pde = kernel_l1pt[l1idx];
1844 
1845 		/*
1846 		 * We're only interested in Coarse mappings.
1847 		 * pmap_extract() can deal with section mappings without
1848 		 * recourse to checking L2 metadata.
1849 		 */
1850 		if ((pde & L1_TYPE_MASK) != L1_TYPE_C)
1851 			continue;
1852 
1853 		/*
1854 		 * Lookup the KVA of this L2 descriptor table
1855 		 */
1856 		pa = (vm_paddr_t)(pde & L1_C_ADDR_MASK);
1857 		ptep = (pt_entry_t *)kernel_pt_lookup(pa);
1858 
1859 		if (ptep == NULL) {
1860 			panic("pmap_bootstrap: No L2 for va 0x%x, pa 0x%lx",
1861 			    (u_int)l1idx << L1_S_SHIFT, (long unsigned int)pa);
1862 		}
1863 
1864 		/*
1865 		 * Fetch the associated L2 metadata structure.
1866 		 * Allocate a new one if necessary.
1867 		 */
1868 		if ((l2 = kernel_pmap->pm_l2[L2_IDX(l1idx)]) == NULL) {
1869 			if (l2next == PMAP_STATIC_L2_SIZE)
1870 				panic("pmap_bootstrap: out of static L2s");
1871 			kernel_pmap->pm_l2[L2_IDX(l1idx)] = l2 =
1872 			    &static_l2[l2next++];
1873 		}
1874 
1875 		/*
1876 		 * One more L1 slot tracked...
1877 		 */
1878 		l2->l2_occupancy++;
1879 
1880 		/*
1881 		 * Fill in the details of the L2 descriptor in the
1882 		 * appropriate bucket.
1883 		 */
1884 		l2b = &l2->l2_bucket[L2_BUCKET(l1idx)];
1885 		l2b->l2b_kva = ptep;
1886 		l2b->l2b_phys = pa;
1887 		l2b->l2b_l1idx = l1idx;
1888 
1889 		/*
1890 		 * Establish an initial occupancy count for this descriptor
1891 		 */
1892 		for (l2idx = 0;
1893 		    l2idx < (L2_TABLE_SIZE_REAL / sizeof(pt_entry_t));
1894 		    l2idx++) {
1895 			if ((ptep[l2idx] & L2_TYPE_MASK) != L2_TYPE_INV) {
1896 				l2b->l2b_occupancy++;
1897 			}
1898 		}
1899 
1900 		/*
1901 		 * Make sure the descriptor itself has the correct cache mode.
1902 		 * If not, fix it, but whine about the problem. Port-meisters
1903 		 * should consider this a clue to fix up their initarm()
1904 		 * function. :)
1905 		 */
1906 		if (pmap_set_pt_cache_mode(kernel_l1pt, (vm_offset_t)ptep)) {
1907 			printf("pmap_bootstrap: WARNING! wrong cache mode for "
1908 			    "L2 pte @ %p\n", ptep);
1909 		}
1910 	}
1911 
1912 
1913 	/*
1914 	 * Ensure the primary (kernel) L1 has the correct cache mode for
1915 	 * a page table. Bitch if it is not correctly set.
1916 	 */
1917 	for (va = (vm_offset_t)kernel_l1pt;
1918 	    va < ((vm_offset_t)kernel_l1pt + L1_TABLE_SIZE); va += PAGE_SIZE) {
1919 		if (pmap_set_pt_cache_mode(kernel_l1pt, va))
1920 			printf("pmap_bootstrap: WARNING! wrong cache mode for "
1921 			    "primary L1 @ 0x%x\n", va);
1922 	}
1923 
1924 	cpu_dcache_wbinv_all();
1925 	cpu_l2cache_wbinv_all();
1926 	cpu_tlb_flushID();
1927 	cpu_cpwait();
1928 
1929 	PMAP_LOCK_INIT(kernel_pmap);
1930 	CPU_FILL(&kernel_pmap->pm_active);
1931 	kernel_pmap->pm_domain = PMAP_DOMAIN_KERNEL;
1932 	TAILQ_INIT(&kernel_pmap->pm_pvchunk);
1933 
1934 	/*
1935 	 * Initialize the global pv list lock.
1936 	 */
1937 	rw_init(&pvh_global_lock, "pmap pv global");
1938 
1939 	/*
1940 	 * Reserve some special page table entries/VA space for temporary
1941 	 * mapping of pages that are being copied or zeroed.
1942 	 */
1943 	for (czp = cpu_czpages, i = 0; i < MAXCPU; ++i, ++czp) {
1944 		mtx_init(&czp->lock, "czpages", NULL, MTX_DEF);
1945 		pmap_alloc_specials(&virtual_avail, 1, &czp->srcva, &czp->srcptep);
1946 		pmap_set_pt_cache_mode(kernel_l1pt, (vm_offset_t)czp->srcptep);
1947 		pmap_alloc_specials(&virtual_avail, 1, &czp->dstva, &czp->dstptep);
1948 		pmap_set_pt_cache_mode(kernel_l1pt, (vm_offset_t)czp->dstptep);
1949 	}
1950 
1951 	size = ((vm_max_kernel_address - pmap_curmaxkvaddr) + L1_S_OFFSET) /
1952 	    L1_S_SIZE;
1953 	pmap_alloc_specials(&virtual_avail,
1954 	    round_page(size * L2_TABLE_SIZE_REAL) / PAGE_SIZE,
1955 	    &pmap_kernel_l2ptp_kva, NULL);
1956 
1957 	size = (size + (L2_BUCKET_SIZE - 1)) / L2_BUCKET_SIZE;
1958 	pmap_alloc_specials(&virtual_avail,
1959 	    round_page(size * sizeof(struct l2_dtable)) / PAGE_SIZE,
1960 	    &pmap_kernel_l2dtable_kva, NULL);
1961 
1962 	pmap_alloc_specials(&virtual_avail,
1963 	    1, (vm_offset_t*)&_tmppt, NULL);
1964 	pmap_alloc_specials(&virtual_avail,
1965 	    MAXDUMPPGS, (vm_offset_t *)&crashdumpmap, NULL);
1966 	SLIST_INIT(&l1_list);
1967 	TAILQ_INIT(&l1_lru_list);
1968 	mtx_init(&l1_lru_lock, "l1 list lock", NULL, MTX_DEF);
1969 	pmap_init_l1(l1, kernel_l1pt);
1970 	cpu_dcache_wbinv_all();
1971 	cpu_l2cache_wbinv_all();
1972 	cpu_tlb_flushID();
1973 	cpu_cpwait();
1974 
1975 	virtual_avail = round_page(virtual_avail);
1976 	virtual_end = vm_max_kernel_address;
1977 	kernel_vm_end = pmap_curmaxkvaddr;
1978 
1979 	pmap_set_pcb_pagedir(kernel_pmap, thread0.td_pcb);
1980 }
1981 
1982 /***************************************************
1983  * Pmap allocation/deallocation routines.
1984  ***************************************************/
1985 
1986 /*
1987  * Release any resources held by the given physical map.
1988  * Called when a pmap initialized by pmap_pinit is being released.
1989  * Should only be called if the map contains no valid mappings.
1990  */
1991 void
1992 pmap_release(pmap_t pmap)
1993 {
1994 	struct pcb *pcb;
1995 
1996 	cpu_tlb_flushID();
1997 	cpu_cpwait();
1998 	if (vector_page < KERNBASE) {
1999 		struct pcb *curpcb = PCPU_GET(curpcb);
2000 		pcb = thread0.td_pcb;
2001 		if (pmap_is_current(pmap)) {
2002 			/*
2003 			 * Frob the L1 entry corresponding to the vector
2004 			 * page so that it contains the kernel pmap's domain
2005 			 * number. This will ensure pmap_remove() does not
2006 			 * pull the current vector page out from under us.
2007 			 */
2008 			critical_enter();
2009 			*pcb->pcb_pl1vec = pcb->pcb_l1vec;
2010 			cpu_domains(pcb->pcb_dacr);
2011 			cpu_setttb(pcb->pcb_pagedir);
2012 			critical_exit();
2013 		}
2014 		pmap_remove(pmap, vector_page, vector_page + PAGE_SIZE);
2015 		/*
2016 		 * Make sure cpu_switch(), et al, DTRT. This is safe to do
2017 		 * since this process has no remaining mappings of its own.
2018 		 */
2019 		curpcb->pcb_pl1vec = pcb->pcb_pl1vec;
2020 		curpcb->pcb_l1vec = pcb->pcb_l1vec;
2021 		curpcb->pcb_dacr = pcb->pcb_dacr;
2022 		curpcb->pcb_pagedir = pcb->pcb_pagedir;
2023 
2024 	}
2025 	pmap_free_l1(pmap);
2026 
2027 	dprintf("pmap_release()\n");
2028 }
2029 
2030 
2031 
2032 /*
2033  * Helper function for pmap_grow_l2_bucket()
2034  */
2035 static __inline int
2036 pmap_grow_map(vm_offset_t va, pt_entry_t cache_mode, vm_paddr_t *pap)
2037 {
2038 	struct l2_bucket *l2b;
2039 	pt_entry_t *ptep;
2040 	vm_paddr_t pa;
2041 	struct vm_page *m;
2042 
2043 	m = vm_page_alloc(NULL, 0, VM_ALLOC_NOOBJ | VM_ALLOC_WIRED);
2044 	if (m == NULL)
2045 		return (1);
2046 	pa = VM_PAGE_TO_PHYS(m);
2047 
2048 	if (pap)
2049 		*pap = pa;
2050 
2051 	l2b = pmap_get_l2_bucket(pmap_kernel(), va);
2052 
2053 	ptep = &l2b->l2b_kva[l2pte_index(va)];
2054 	*ptep = L2_S_PROTO | pa | cache_mode | L2_S_REF;
2055 	pmap_set_prot(ptep, VM_PROT_READ | VM_PROT_WRITE, 0);
2056 	PTE_SYNC(ptep);
2057 	cpu_tlb_flushD_SE(va);
2058 	cpu_cpwait();
2059 
2060 	return (0);
2061 }
2062 
2063 /*
2064  * This is the same as pmap_alloc_l2_bucket(), except that it is only
2065  * used by pmap_growkernel().
2066  */
2067 static __inline struct l2_bucket *
2068 pmap_grow_l2_bucket(pmap_t pmap, vm_offset_t va)
2069 {
2070 	struct l2_dtable *l2;
2071 	struct l2_bucket *l2b;
2072 	struct l1_ttable *l1;
2073 	pd_entry_t *pl1pd;
2074 	u_short l1idx;
2075 	vm_offset_t nva;
2076 
2077 	l1idx = L1_IDX(va);
2078 
2079 	if ((l2 = pmap->pm_l2[L2_IDX(l1idx)]) == NULL) {
2080 		/*
2081 		 * No mapping at this address, as there is
2082 		 * no entry in the L1 table.
2083 		 * Need to allocate a new l2_dtable.
2084 		 */
2085 		nva = pmap_kernel_l2dtable_kva;
2086 		if ((nva & PAGE_MASK) == 0) {
2087 			/*
2088 			 * Need to allocate a backing page
2089 			 */
2090 			if (pmap_grow_map(nva, pte_l2_s_cache_mode, NULL))
2091 				return (NULL);
2092 		}
2093 
2094 		l2 = (struct l2_dtable *)nva;
2095 		nva += sizeof(struct l2_dtable);
2096 
2097 		if ((nva & PAGE_MASK) < (pmap_kernel_l2dtable_kva &
2098 		    PAGE_MASK)) {
2099 			/*
2100 			 * The new l2_dtable straddles a page boundary.
2101 			 * Map in another page to cover it.
2102 			 */
2103 			if (pmap_grow_map(nva, pte_l2_s_cache_mode, NULL))
2104 				return (NULL);
2105 		}
2106 
2107 		pmap_kernel_l2dtable_kva = nva;
2108 
2109 		/*
2110 		 * Link it into the parent pmap
2111 		 */
2112 		pmap->pm_l2[L2_IDX(l1idx)] = l2;
2113 		memset(l2, 0, sizeof(*l2));
2114 	}
2115 
2116 	l2b = &l2->l2_bucket[L2_BUCKET(l1idx)];
2117 
2118 	/*
2119 	 * Fetch pointer to the L2 page table associated with the address.
2120 	 */
2121 	if (l2b->l2b_kva == NULL) {
2122 		pt_entry_t *ptep;
2123 
2124 		/*
2125 		 * No L2 page table has been allocated. Chances are, this
2126 		 * is because we just allocated the l2_dtable, above.
2127 		 */
2128 		nva = pmap_kernel_l2ptp_kva;
2129 		ptep = (pt_entry_t *)nva;
2130 		if ((nva & PAGE_MASK) == 0) {
2131 			/*
2132 			 * Need to allocate a backing page
2133 			 */
2134 			if (pmap_grow_map(nva, pte_l2_s_cache_mode_pt,
2135 			    &pmap_kernel_l2ptp_phys))
2136 				return (NULL);
2137 		}
2138 		memset(ptep, 0, L2_TABLE_SIZE_REAL);
2139 		l2->l2_occupancy++;
2140 		l2b->l2b_kva = ptep;
2141 		l2b->l2b_l1idx = l1idx;
2142 		l2b->l2b_phys = pmap_kernel_l2ptp_phys;
2143 
2144 		pmap_kernel_l2ptp_kva += L2_TABLE_SIZE_REAL;
2145 		pmap_kernel_l2ptp_phys += L2_TABLE_SIZE_REAL;
2146 	}
2147 
2148 	/* Distribute new L1 entry to all other L1s */
2149 	SLIST_FOREACH(l1, &l1_list, l1_link) {
2150 			pl1pd = &l1->l1_kva[L1_IDX(va)];
2151 			*pl1pd = l2b->l2b_phys | L1_C_DOM(PMAP_DOMAIN_KERNEL) |
2152 			    L1_C_PROTO;
2153 			PTE_SYNC(pl1pd);
2154 	}
2155 	cpu_tlb_flushID_SE(va);
2156 	cpu_cpwait();
2157 
2158 	return (l2b);
2159 }
2160 
2161 
2162 /*
2163  * grow the number of kernel page table entries, if needed
2164  */
2165 void
2166 pmap_growkernel(vm_offset_t addr)
2167 {
2168 	pmap_t kpmap = pmap_kernel();
2169 
2170 	if (addr <= pmap_curmaxkvaddr)
2171 		return;		/* we are OK */
2172 
2173 	/*
2174 	 * whoops!   we need to add kernel PTPs
2175 	 */
2176 
2177 	/* Map 1MB at a time */
2178 	for (; pmap_curmaxkvaddr < addr; pmap_curmaxkvaddr += L1_S_SIZE)
2179 		pmap_grow_l2_bucket(kpmap, pmap_curmaxkvaddr);
2180 
2181 	kernel_vm_end = pmap_curmaxkvaddr;
2182 }
2183 
2184 /*
2185  * Returns TRUE if the given page is mapped individually or as part of
2186  * a 1MB section.  Otherwise, returns FALSE.
2187  */
2188 boolean_t
2189 pmap_page_is_mapped(vm_page_t m)
2190 {
2191 	boolean_t rv;
2192 
2193 	if ((m->oflags & VPO_UNMANAGED) != 0)
2194 		return (FALSE);
2195 	rw_wlock(&pvh_global_lock);
2196 	rv = !TAILQ_EMPTY(&m->md.pv_list) ||
2197 	    ((m->flags & PG_FICTITIOUS) == 0 &&
2198 	    !TAILQ_EMPTY(&pa_to_pvh(VM_PAGE_TO_PHYS(m))->pv_list));
2199 	rw_wunlock(&pvh_global_lock);
2200 	return (rv);
2201 }
2202 
2203 /*
2204  * Remove all pages from specified address space
2205  * this aids process exit speeds.  Also, this code
2206  * is special cased for current process only, but
2207  * can have the more generic (and slightly slower)
2208  * mode enabled.  This is much faster than pmap_remove
2209  * in the case of running down an entire address space.
2210  */
2211 void
2212 pmap_remove_pages(pmap_t pmap)
2213 {
2214 	struct pv_entry *pv;
2215  	struct l2_bucket *l2b = NULL;
2216 	struct pv_chunk *pc, *npc;
2217 	struct md_page *pvh;
2218 	pd_entry_t *pl1pd, l1pd;
2219  	pt_entry_t *ptep;
2220  	vm_page_t m, mt;
2221 	vm_offset_t va;
2222 	uint32_t inuse, bitmask;
2223 	int allfree, bit, field, idx;
2224 
2225  	rw_wlock(&pvh_global_lock);
2226  	PMAP_LOCK(pmap);
2227 
2228 	TAILQ_FOREACH_SAFE(pc, &pmap->pm_pvchunk, pc_list, npc) {
2229 		allfree = 1;
2230 		for (field = 0; field < _NPCM; field++) {
2231 			inuse = ~pc->pc_map[field] & pc_freemask[field];
2232 			while (inuse != 0) {
2233 				bit = ffs(inuse) - 1;
2234 				bitmask = 1ul << bit;
2235 				idx = field * sizeof(inuse) * NBBY + bit;
2236 				pv = &pc->pc_pventry[idx];
2237 				va = pv->pv_va;
2238 				inuse &= ~bitmask;
2239 				if (pv->pv_flags & PVF_WIRED) {
2240 					/* Cannot remove wired pages now. */
2241 					allfree = 0;
2242 					continue;
2243 				}
2244 				pl1pd = &pmap->pm_l1->l1_kva[L1_IDX(va)];
2245 				l1pd = *pl1pd;
2246 				l2b = pmap_get_l2_bucket(pmap, va);
2247 				if ((l1pd & L1_TYPE_MASK) == L1_S_PROTO) {
2248 					pvh = pa_to_pvh(l1pd & L1_S_FRAME);
2249 					TAILQ_REMOVE(&pvh->pv_list, pv, pv_list);
2250 					if (TAILQ_EMPTY(&pvh->pv_list)) {
2251 						m = PHYS_TO_VM_PAGE(l1pd & L1_S_FRAME);
2252 						KASSERT((vm_offset_t)m >= KERNBASE,
2253 						    ("Trying to access non-existent page "
2254 						     "va %x l1pd %x", trunc_1mpage(va), l1pd));
2255 						for (mt = m; mt < &m[L2_PTE_NUM_TOTAL]; mt++) {
2256 							if (TAILQ_EMPTY(&mt->md.pv_list))
2257 								vm_page_aflag_clear(mt, PGA_WRITEABLE);
2258 						}
2259 					}
2260 					if (l2b != NULL) {
2261 						KASSERT(l2b->l2b_occupancy == L2_PTE_NUM_TOTAL,
2262 						    ("pmap_remove_pages: l2_bucket occupancy error"));
2263 						pmap_free_l2_bucket(pmap, l2b, L2_PTE_NUM_TOTAL);
2264 					}
2265 					pmap->pm_stats.resident_count -= L2_PTE_NUM_TOTAL;
2266 					*pl1pd = 0;
2267 					PTE_SYNC(pl1pd);
2268 				} else {
2269 					KASSERT(l2b != NULL,
2270 					    ("No L2 bucket in pmap_remove_pages"));
2271 					ptep = &l2b->l2b_kva[l2pte_index(va)];
2272 					m = PHYS_TO_VM_PAGE(l2pte_pa(*ptep));
2273 					KASSERT((vm_offset_t)m >= KERNBASE,
2274 					    ("Trying to access non-existent page "
2275 					     "va %x pte %x", va, *ptep));
2276 					TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
2277 					if (TAILQ_EMPTY(&m->md.pv_list) &&
2278 					    (m->flags & PG_FICTITIOUS) == 0) {
2279 						pvh = pa_to_pvh(l2pte_pa(*ptep));
2280 						if (TAILQ_EMPTY(&pvh->pv_list))
2281 							vm_page_aflag_clear(m, PGA_WRITEABLE);
2282 					}
2283 					*ptep = 0;
2284 					PTE_SYNC(ptep);
2285 					pmap_free_l2_bucket(pmap, l2b, 1);
2286 					pmap->pm_stats.resident_count--;
2287 				}
2288 
2289 				/* Mark free */
2290 				PV_STAT(pv_entry_frees++);
2291 				PV_STAT(pv_entry_spare++);
2292 				pv_entry_count--;
2293 				pc->pc_map[field] |= bitmask;
2294 			}
2295 		}
2296 		if (allfree) {
2297 			TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
2298 			pmap_free_pv_chunk(pc);
2299 		}
2300 
2301 	}
2302 
2303  	rw_wunlock(&pvh_global_lock);
2304  	cpu_tlb_flushID();
2305  	cpu_cpwait();
2306  	PMAP_UNLOCK(pmap);
2307 }
2308 
2309 
2310 /***************************************************
2311  * Low level mapping routines.....
2312  ***************************************************/
2313 
2314 #ifdef ARM_HAVE_SUPERSECTIONS
2315 /* Map a super section into the KVA. */
2316 
2317 void
2318 pmap_kenter_supersection(vm_offset_t va, uint64_t pa, int flags)
2319 {
2320 	pd_entry_t pd = L1_S_PROTO | L1_S_SUPERSEC | (pa & L1_SUP_FRAME) |
2321 	    (((pa >> 32) & 0xf) << 20) | L1_S_PROT(PTE_KERNEL,
2322 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE) |
2323 	    L1_S_DOM(PMAP_DOMAIN_KERNEL);
2324 	struct l1_ttable *l1;
2325 	vm_offset_t va0, va_end;
2326 
2327 	KASSERT(((va | pa) & L1_SUP_OFFSET) == 0,
2328 	    ("Not a valid super section mapping"));
2329 	if (flags & SECTION_CACHE)
2330 		pd |= pte_l1_s_cache_mode;
2331 	else if (flags & SECTION_PT)
2332 		pd |= pte_l1_s_cache_mode_pt;
2333 
2334 	va0 = va & L1_SUP_FRAME;
2335 	va_end = va + L1_SUP_SIZE;
2336 	SLIST_FOREACH(l1, &l1_list, l1_link) {
2337 		va = va0;
2338 		for (; va < va_end; va += L1_S_SIZE) {
2339 			l1->l1_kva[L1_IDX(va)] = pd;
2340 			PTE_SYNC(&l1->l1_kva[L1_IDX(va)]);
2341 		}
2342 	}
2343 }
2344 #endif
2345 
2346 /* Map a section into the KVA. */
2347 
2348 void
2349 pmap_kenter_section(vm_offset_t va, vm_offset_t pa, int flags)
2350 {
2351 	pd_entry_t pd = L1_S_PROTO | pa | L1_S_PROT(PTE_KERNEL,
2352 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE) | L1_S_REF |
2353 	    L1_S_DOM(PMAP_DOMAIN_KERNEL);
2354 	struct l1_ttable *l1;
2355 
2356 	KASSERT(((va | pa) & L1_S_OFFSET) == 0,
2357 	    ("Not a valid section mapping"));
2358 	if (flags & SECTION_CACHE)
2359 		pd |= pte_l1_s_cache_mode;
2360 	else if (flags & SECTION_PT)
2361 		pd |= pte_l1_s_cache_mode_pt;
2362 
2363 	SLIST_FOREACH(l1, &l1_list, l1_link) {
2364 		l1->l1_kva[L1_IDX(va)] = pd;
2365 		PTE_SYNC(&l1->l1_kva[L1_IDX(va)]);
2366 	}
2367 	cpu_tlb_flushID_SE(va);
2368 	cpu_cpwait();
2369 }
2370 
2371 /*
2372  * Make a temporary mapping for a physical address.  This is only intended
2373  * to be used for panic dumps.
2374  */
2375 void *
2376 pmap_kenter_temporary(vm_paddr_t pa, int i)
2377 {
2378 	vm_offset_t va;
2379 
2380 	va = (vm_offset_t)crashdumpmap + (i * PAGE_SIZE);
2381 	pmap_kenter(va, pa);
2382 	return ((void *)crashdumpmap);
2383 }
2384 
2385 /*
2386  * add a wired page to the kva
2387  * note that in order for the mapping to take effect -- you
2388  * should do a invltlb after doing the pmap_kenter...
2389  */
2390 static PMAP_INLINE void
2391 pmap_kenter_internal(vm_offset_t va, vm_offset_t pa, int flags)
2392 {
2393 	struct l2_bucket *l2b;
2394 	pt_entry_t *ptep;
2395 	pt_entry_t opte;
2396 
2397 	PDEBUG(1, printf("pmap_kenter: va = %08x, pa = %08x\n",
2398 	    (uint32_t) va, (uint32_t) pa));
2399 
2400 
2401 	l2b = pmap_get_l2_bucket(pmap_kernel(), va);
2402 	if (l2b == NULL)
2403 		l2b = pmap_grow_l2_bucket(pmap_kernel(), va);
2404 	KASSERT(l2b != NULL, ("No L2 Bucket"));
2405 
2406 	ptep = &l2b->l2b_kva[l2pte_index(va)];
2407 	opte = *ptep;
2408 
2409 	if (flags & KENTER_CACHE)
2410 		*ptep = L2_S_PROTO | l2s_mem_types[PTE_CACHE] | pa | L2_S_REF;
2411 	else if (flags & KENTER_DEVICE)
2412 		*ptep = L2_S_PROTO | l2s_mem_types[PTE_DEVICE] | pa | L2_S_REF;
2413 	else
2414 		*ptep = L2_S_PROTO | l2s_mem_types[PTE_NOCACHE] | pa | L2_S_REF;
2415 
2416 	if (flags & KENTER_CACHE) {
2417 		pmap_set_prot(ptep, VM_PROT_READ | VM_PROT_WRITE,
2418 		    flags & KENTER_USER);
2419 	} else {
2420 		pmap_set_prot(ptep, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE,
2421 		    0);
2422 	}
2423 
2424 	PTE_SYNC(ptep);
2425 	if (l2pte_valid(opte)) {
2426 		if (L2_S_EXECUTABLE(opte) || L2_S_EXECUTABLE(*ptep))
2427 			cpu_tlb_flushID_SE(va);
2428 		else
2429 			cpu_tlb_flushD_SE(va);
2430 	} else {
2431 		if (opte == 0)
2432 			l2b->l2b_occupancy++;
2433 	}
2434 	cpu_cpwait();
2435 
2436 	PDEBUG(1, printf("pmap_kenter: pte = %08x, opte = %08x, npte = %08x\n",
2437 	    (uint32_t) ptep, opte, *ptep));
2438 }
2439 
2440 void
2441 pmap_kenter(vm_offset_t va, vm_paddr_t pa)
2442 {
2443 	pmap_kenter_internal(va, pa, KENTER_CACHE);
2444 }
2445 
2446 void
2447 pmap_kenter_nocache(vm_offset_t va, vm_paddr_t pa)
2448 {
2449 
2450 	pmap_kenter_internal(va, pa, 0);
2451 }
2452 
2453 void
2454 pmap_kenter_device(vm_offset_t va, vm_size_t size, vm_paddr_t pa)
2455 {
2456 	vm_offset_t sva;
2457 
2458 	KASSERT((size & PAGE_MASK) == 0,
2459 	    ("%s: device mapping not page-sized", __func__));
2460 
2461 	sva = va;
2462 	while (size != 0) {
2463 		pmap_kenter_internal(va, pa, KENTER_DEVICE);
2464 		va += PAGE_SIZE;
2465 		pa += PAGE_SIZE;
2466 		size -= PAGE_SIZE;
2467 	}
2468 }
2469 
2470 void
2471 pmap_kremove_device(vm_offset_t va, vm_size_t size)
2472 {
2473 	vm_offset_t sva;
2474 
2475 	KASSERT((size & PAGE_MASK) == 0,
2476 	    ("%s: device mapping not page-sized", __func__));
2477 
2478 	sva = va;
2479 	while (size != 0) {
2480 		pmap_kremove(va);
2481 		va += PAGE_SIZE;
2482 		size -= PAGE_SIZE;
2483 	}
2484 }
2485 
2486 void
2487 pmap_kenter_user(vm_offset_t va, vm_paddr_t pa)
2488 {
2489 
2490 	pmap_kenter_internal(va, pa, KENTER_CACHE|KENTER_USER);
2491 	/*
2492 	 * Call pmap_fault_fixup now, to make sure we'll have no exception
2493 	 * at the first use of the new address, or bad things will happen,
2494 	 * as we use one of these addresses in the exception handlers.
2495 	 */
2496 	pmap_fault_fixup(pmap_kernel(), va, VM_PROT_READ|VM_PROT_WRITE, 1);
2497 }
2498 
2499 vm_paddr_t
2500 pmap_kextract(vm_offset_t va)
2501 {
2502 
2503 	if (kernel_vm_end == 0)
2504 		return (0);
2505 	return (pmap_extract_locked(kernel_pmap, va));
2506 }
2507 
2508 /*
2509  * remove a page from the kernel pagetables
2510  */
2511 void
2512 pmap_kremove(vm_offset_t va)
2513 {
2514 	struct l2_bucket *l2b;
2515 	pt_entry_t *ptep, opte;
2516 
2517 	l2b = pmap_get_l2_bucket(pmap_kernel(), va);
2518 	if (!l2b)
2519 		return;
2520 	KASSERT(l2b != NULL, ("No L2 Bucket"));
2521 	ptep = &l2b->l2b_kva[l2pte_index(va)];
2522 	opte = *ptep;
2523 	if (l2pte_valid(opte)) {
2524 		va = va & ~PAGE_MASK;
2525 		*ptep = 0;
2526 		PTE_SYNC(ptep);
2527 		if (L2_S_EXECUTABLE(opte))
2528 			cpu_tlb_flushID_SE(va);
2529 		else
2530 			cpu_tlb_flushD_SE(va);
2531 		cpu_cpwait();
2532 	}
2533 }
2534 
2535 
2536 /*
2537  *	Used to map a range of physical addresses into kernel
2538  *	virtual address space.
2539  *
2540  *	The value passed in '*virt' is a suggested virtual address for
2541  *	the mapping. Architectures which can support a direct-mapped
2542  *	physical to virtual region can return the appropriate address
2543  *	within that region, leaving '*virt' unchanged. Other
2544  *	architectures should map the pages starting at '*virt' and
2545  *	update '*virt' with the first usable address after the mapped
2546  *	region.
2547  */
2548 vm_offset_t
2549 pmap_map(vm_offset_t *virt, vm_offset_t start, vm_offset_t end, int prot)
2550 {
2551 	vm_offset_t sva = *virt;
2552 	vm_offset_t va = sva;
2553 
2554 	PDEBUG(1, printf("pmap_map: virt = %08x, start = %08x, end = %08x, "
2555 	    "prot = %d\n", (uint32_t) *virt, (uint32_t) start, (uint32_t) end,
2556 	    prot));
2557 
2558 	while (start < end) {
2559 		pmap_kenter(va, start);
2560 		va += PAGE_SIZE;
2561 		start += PAGE_SIZE;
2562 	}
2563 	*virt = va;
2564 	return (sva);
2565 }
2566 
2567 /*
2568  * Add a list of wired pages to the kva
2569  * this routine is only used for temporary
2570  * kernel mappings that do not need to have
2571  * page modification or references recorded.
2572  * Note that old mappings are simply written
2573  * over.  The page *must* be wired.
2574  */
2575 void
2576 pmap_qenter(vm_offset_t va, vm_page_t *m, int count)
2577 {
2578 	int i;
2579 
2580 	for (i = 0; i < count; i++) {
2581 		pmap_kenter_internal(va, VM_PAGE_TO_PHYS(m[i]),
2582 		    KENTER_CACHE);
2583 		va += PAGE_SIZE;
2584 	}
2585 }
2586 
2587 
2588 /*
2589  * this routine jerks page mappings from the
2590  * kernel -- it is meant only for temporary mappings.
2591  */
2592 void
2593 pmap_qremove(vm_offset_t va, int count)
2594 {
2595 	int i;
2596 
2597 	for (i = 0; i < count; i++) {
2598 		if (vtophys(va))
2599 			pmap_kremove(va);
2600 
2601 		va += PAGE_SIZE;
2602 	}
2603 }
2604 
2605 
2606 /*
2607  * pmap_object_init_pt preloads the ptes for a given object
2608  * into the specified pmap.  This eliminates the blast of soft
2609  * faults on process startup and immediately after an mmap.
2610  */
2611 void
2612 pmap_object_init_pt(pmap_t pmap, vm_offset_t addr, vm_object_t object,
2613     vm_pindex_t pindex, vm_size_t size)
2614 {
2615 
2616 	VM_OBJECT_ASSERT_WLOCKED(object);
2617 	KASSERT(object->type == OBJT_DEVICE || object->type == OBJT_SG,
2618 	    ("pmap_object_init_pt: non-device object"));
2619 }
2620 
2621 
2622 /*
2623  *	pmap_is_prefaultable:
2624  *
2625  *	Return whether or not the specified virtual address is elgible
2626  *	for prefault.
2627  */
2628 boolean_t
2629 pmap_is_prefaultable(pmap_t pmap, vm_offset_t addr)
2630 {
2631 	pd_entry_t *pdep;
2632 	pt_entry_t *ptep;
2633 
2634 	if (!pmap_get_pde_pte(pmap, addr, &pdep, &ptep))
2635 		return (FALSE);
2636 	KASSERT((pdep != NULL && (l1pte_section_p(*pdep) || ptep != NULL)),
2637 	    ("Valid mapping but no pte ?"));
2638 	if (*pdep != 0 && !l1pte_section_p(*pdep))
2639 		if (*ptep == 0)
2640 			return (TRUE);
2641 	return (FALSE);
2642 }
2643 
2644 /*
2645  * Fetch pointers to the PDE/PTE for the given pmap/VA pair.
2646  * Returns TRUE if the mapping exists, else FALSE.
2647  *
2648  * NOTE: This function is only used by a couple of arm-specific modules.
2649  * It is not safe to take any pmap locks here, since we could be right
2650  * in the middle of debugging the pmap anyway...
2651  *
2652  * It is possible for this routine to return FALSE even though a valid
2653  * mapping does exist. This is because we don't lock, so the metadata
2654  * state may be inconsistent.
2655  *
2656  * NOTE: We can return a NULL *ptp in the case where the L1 pde is
2657  * a "section" mapping.
2658  */
2659 boolean_t
2660 pmap_get_pde_pte(pmap_t pmap, vm_offset_t va, pd_entry_t **pdp,
2661     pt_entry_t **ptp)
2662 {
2663 	struct l2_dtable *l2;
2664 	pd_entry_t *pl1pd, l1pd;
2665 	pt_entry_t *ptep;
2666 	u_short l1idx;
2667 
2668 	if (pmap->pm_l1 == NULL)
2669 		return (FALSE);
2670 
2671 	l1idx = L1_IDX(va);
2672 	*pdp = pl1pd = &pmap->pm_l1->l1_kva[l1idx];
2673 	l1pd = *pl1pd;
2674 
2675 	if (l1pte_section_p(l1pd)) {
2676 		*ptp = NULL;
2677 		return (TRUE);
2678 	}
2679 
2680 	if (pmap->pm_l2 == NULL)
2681 		return (FALSE);
2682 
2683 	l2 = pmap->pm_l2[L2_IDX(l1idx)];
2684 
2685 	if (l2 == NULL ||
2686 	    (ptep = l2->l2_bucket[L2_BUCKET(l1idx)].l2b_kva) == NULL) {
2687 		return (FALSE);
2688 	}
2689 
2690 	*ptp = &ptep[l2pte_index(va)];
2691 	return (TRUE);
2692 }
2693 
2694 /*
2695  *      Routine:        pmap_remove_all
2696  *      Function:
2697  *              Removes this physical page from
2698  *              all physical maps in which it resides.
2699  *              Reflects back modify bits to the pager.
2700  *
2701  *      Notes:
2702  *              Original versions of this routine were very
2703  *              inefficient because they iteratively called
2704  *              pmap_remove (slow...)
2705  */
2706 void
2707 pmap_remove_all(vm_page_t m)
2708 {
2709 	struct md_page *pvh;
2710 	pv_entry_t pv;
2711 	pmap_t pmap;
2712 	pt_entry_t *ptep;
2713 	struct l2_bucket *l2b;
2714 	boolean_t flush = FALSE;
2715 	pmap_t curpmap;
2716 	u_int is_exec = 0;
2717 
2718 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
2719 	    ("pmap_remove_all: page %p is not managed", m));
2720 	rw_wlock(&pvh_global_lock);
2721 	if ((m->flags & PG_FICTITIOUS) != 0)
2722 		goto small_mappings;
2723 	pvh = pa_to_pvh(VM_PAGE_TO_PHYS(m));
2724 	while ((pv = TAILQ_FIRST(&pvh->pv_list)) != NULL) {
2725 		pmap = PV_PMAP(pv);
2726 		PMAP_LOCK(pmap);
2727 		pd_entry_t *pl1pd;
2728 		pl1pd = &pmap->pm_l1->l1_kva[L1_IDX(pv->pv_va)];
2729 		KASSERT((*pl1pd & L1_TYPE_MASK) == L1_S_PROTO,
2730 		    ("pmap_remove_all: valid section mapping expected"));
2731 		(void)pmap_demote_section(pmap, pv->pv_va);
2732 		PMAP_UNLOCK(pmap);
2733 	}
2734 small_mappings:
2735 	curpmap = vmspace_pmap(curproc->p_vmspace);
2736 	while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) {
2737 		pmap = PV_PMAP(pv);
2738 		if (flush == FALSE && (pmap == curpmap ||
2739 		    pmap == pmap_kernel()))
2740 			flush = TRUE;
2741 
2742 		PMAP_LOCK(pmap);
2743 		l2b = pmap_get_l2_bucket(pmap, pv->pv_va);
2744 		KASSERT(l2b != NULL, ("No l2 bucket"));
2745 		ptep = &l2b->l2b_kva[l2pte_index(pv->pv_va)];
2746 		is_exec |= PTE_BEEN_EXECD(*ptep);
2747 		*ptep = 0;
2748 		if (pmap_is_current(pmap))
2749 			PTE_SYNC(ptep);
2750 		pmap_free_l2_bucket(pmap, l2b, 1);
2751 		pmap->pm_stats.resident_count--;
2752 		TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
2753 		if (pv->pv_flags & PVF_WIRED)
2754 			pmap->pm_stats.wired_count--;
2755 		pmap_free_pv_entry(pmap, pv);
2756 		PMAP_UNLOCK(pmap);
2757 	}
2758 
2759 	if (flush) {
2760 		if (is_exec)
2761 			cpu_tlb_flushID();
2762 		else
2763 			cpu_tlb_flushD();
2764 		cpu_cpwait();
2765 	}
2766 	vm_page_aflag_clear(m, PGA_WRITEABLE);
2767 	rw_wunlock(&pvh_global_lock);
2768 }
2769 
2770 int
2771 pmap_change_attr(vm_offset_t sva, vm_size_t len, int mode)
2772 {
2773 	vm_offset_t base, offset, tmpva;
2774 	vm_size_t size;
2775 	struct l2_bucket *l2b;
2776 	pt_entry_t *ptep, pte;
2777 	vm_offset_t next_bucket;
2778 
2779 	PMAP_LOCK(kernel_pmap);
2780 
2781 	base = trunc_page(sva);
2782 	offset = sva & PAGE_MASK;
2783 	size = roundup(offset + len, PAGE_SIZE);
2784 
2785 	for (tmpva = base; tmpva < base + size; ) {
2786 		next_bucket = L2_NEXT_BUCKET(tmpva);
2787 		if (next_bucket > base + size)
2788 			next_bucket = base + size;
2789 
2790 		l2b = pmap_get_l2_bucket(kernel_pmap, tmpva);
2791 		if (l2b == NULL) {
2792 			tmpva = next_bucket;
2793 			continue;
2794 		}
2795 
2796 		ptep = &l2b->l2b_kva[l2pte_index(tmpva)];
2797 
2798 		if (*ptep == 0) {
2799 			PMAP_UNLOCK(kernel_pmap);
2800 			return(EINVAL);
2801 		}
2802 
2803 		pte = *ptep &~ L2_S_CACHE_MASK;
2804 		cpu_idcache_wbinv_range(tmpva, PAGE_SIZE);
2805 		pmap_l2cache_wbinv_range(tmpva, pte & L2_S_FRAME, PAGE_SIZE);
2806 		*ptep = pte;
2807 		cpu_tlb_flushID_SE(tmpva);
2808 		cpu_cpwait();
2809 
2810 		dprintf("%s: for va:%x ptep:%x pte:%x\n",
2811 		    __func__, tmpva, (uint32_t)ptep, pte);
2812 		tmpva += PAGE_SIZE;
2813 	}
2814 
2815 	PMAP_UNLOCK(kernel_pmap);
2816 
2817 	return (0);
2818 }
2819 
2820 /*
2821  *	Set the physical protection on the
2822  *	specified range of this map as requested.
2823  */
2824 void
2825 pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot)
2826 {
2827 	struct l2_bucket *l2b;
2828 	struct md_page *pvh;
2829 	struct pv_entry *pve;
2830 	pd_entry_t *pl1pd, l1pd;
2831 	pt_entry_t *ptep, pte;
2832 	vm_offset_t next_bucket;
2833 	u_int is_exec, is_refd;
2834 	int flush;
2835 
2836 	if ((prot & VM_PROT_READ) == 0) {
2837 		pmap_remove(pmap, sva, eva);
2838 		return;
2839 	}
2840 
2841 	if (prot & VM_PROT_WRITE) {
2842 		/*
2843 		 * If this is a read->write transition, just ignore it and let
2844 		 * vm_fault() take care of it later.
2845 		 */
2846 		return;
2847 	}
2848 
2849 	rw_wlock(&pvh_global_lock);
2850 	PMAP_LOCK(pmap);
2851 
2852 	/*
2853 	 * OK, at this point, we know we're doing write-protect operation.
2854 	 * If the pmap is active, write-back the range.
2855 	 */
2856 
2857 	flush = ((eva - sva) >= (PAGE_SIZE * 4)) ? 0 : -1;
2858 	is_exec = is_refd = 0;
2859 
2860 	while (sva < eva) {
2861 		next_bucket = L2_NEXT_BUCKET(sva);
2862 		/*
2863 		 * Check for large page.
2864 		 */
2865 		pl1pd = &pmap->pm_l1->l1_kva[L1_IDX(sva)];
2866 		l1pd = *pl1pd;
2867 		if ((l1pd & L1_TYPE_MASK) == L1_S_PROTO) {
2868 			KASSERT(pmap != pmap_kernel(),
2869 			    ("pmap_protect: trying to modify "
2870 			    "kernel section protections"));
2871 			/*
2872 			 * Are we protecting the entire large page? If not,
2873 			 * demote the mapping and fall through.
2874 			 */
2875 			if (sva + L1_S_SIZE == next_bucket &&
2876 			    eva >= next_bucket) {
2877 				l1pd &= ~(L1_S_PROT_MASK | L1_S_XN);
2878 				if (!(prot & VM_PROT_EXECUTE))
2879 					l1pd |= L1_S_XN;
2880 				/*
2881 				 * At this point we are always setting
2882 				 * write-protect bit.
2883 				 */
2884 				l1pd |= L1_S_APX;
2885 				/* All managed superpages are user pages. */
2886 				l1pd |= L1_S_PROT_U;
2887 				*pl1pd = l1pd;
2888 				PTE_SYNC(pl1pd);
2889 				pvh = pa_to_pvh(l1pd & L1_S_FRAME);
2890 				pve = pmap_find_pv(pvh, pmap,
2891 				    trunc_1mpage(sva));
2892 				pve->pv_flags &= ~PVF_WRITE;
2893 				sva = next_bucket;
2894 				continue;
2895 			} else if (!pmap_demote_section(pmap, sva)) {
2896 				/* The large page mapping was destroyed. */
2897 				sva = next_bucket;
2898 				continue;
2899 			}
2900 		}
2901 		if (next_bucket > eva)
2902 			next_bucket = eva;
2903 		l2b = pmap_get_l2_bucket(pmap, sva);
2904 		if (l2b == NULL) {
2905 			sva = next_bucket;
2906 			continue;
2907 		}
2908 
2909 		ptep = &l2b->l2b_kva[l2pte_index(sva)];
2910 
2911 		while (sva < next_bucket) {
2912 			if ((pte = *ptep) != 0 && L2_S_WRITABLE(pte)) {
2913 				struct vm_page *m;
2914 
2915 				m = PHYS_TO_VM_PAGE(l2pte_pa(pte));
2916 				pmap_set_prot(ptep, prot,
2917 				    !(pmap == pmap_kernel()));
2918 				PTE_SYNC(ptep);
2919 
2920 				pmap_modify_pv(m, pmap, sva, PVF_WRITE, 0);
2921 
2922 				if (flush >= 0) {
2923 					flush++;
2924 					is_exec |= PTE_BEEN_EXECD(pte);
2925 					is_refd |= PTE_BEEN_REFD(pte);
2926 				} else {
2927 					if (PTE_BEEN_EXECD(pte))
2928 						cpu_tlb_flushID_SE(sva);
2929 					else if (PTE_BEEN_REFD(pte))
2930 						cpu_tlb_flushD_SE(sva);
2931 				}
2932 			}
2933 
2934 			sva += PAGE_SIZE;
2935 			ptep++;
2936 		}
2937 	}
2938 
2939 
2940 	if (flush) {
2941 		if (is_exec)
2942 			cpu_tlb_flushID();
2943 		else
2944 		if (is_refd)
2945 			cpu_tlb_flushD();
2946 		cpu_cpwait();
2947 	}
2948 	rw_wunlock(&pvh_global_lock);
2949 
2950 	PMAP_UNLOCK(pmap);
2951 }
2952 
2953 
2954 /*
2955  *	Insert the given physical page (p) at
2956  *	the specified virtual address (v) in the
2957  *	target physical map with the protection requested.
2958  *
2959  *	If specified, the page will be wired down, meaning
2960  *	that the related pte can not be reclaimed.
2961  *
2962  *	NB:  This is the only routine which MAY NOT lazy-evaluate
2963  *	or lose information.  That is, this routine must actually
2964  *	insert this page into the given map NOW.
2965  */
2966 
2967 int
2968 pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot,
2969     u_int flags, int8_t psind __unused)
2970 {
2971 	struct l2_bucket *l2b;
2972 	int rv;
2973 
2974 	rw_wlock(&pvh_global_lock);
2975 	PMAP_LOCK(pmap);
2976 	rv = pmap_enter_locked(pmap, va, m, prot, flags);
2977 	if (rv == KERN_SUCCESS) {
2978 		/*
2979 		 * If both the l2b_occupancy and the reservation are fully
2980 		 * populated, then attempt promotion.
2981 		 */
2982 		l2b = pmap_get_l2_bucket(pmap, va);
2983 		if (l2b != NULL && l2b->l2b_occupancy == L2_PTE_NUM_TOTAL &&
2984 		    sp_enabled && (m->flags & PG_FICTITIOUS) == 0 &&
2985 		    vm_reserv_level_iffullpop(m) == 0)
2986 			pmap_promote_section(pmap, va);
2987 	}
2988 	PMAP_UNLOCK(pmap);
2989 	rw_wunlock(&pvh_global_lock);
2990 	return (rv);
2991 }
2992 
2993 /*
2994  *	The pvh global and pmap locks must be held.
2995  */
2996 static int
2997 pmap_enter_locked(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot,
2998     u_int flags)
2999 {
3000 	struct l2_bucket *l2b = NULL;
3001 	struct vm_page *om;
3002 	struct pv_entry *pve = NULL;
3003 	pd_entry_t *pl1pd, l1pd;
3004 	pt_entry_t *ptep, npte, opte;
3005 	u_int nflags;
3006 	u_int is_exec, is_refd;
3007 	vm_paddr_t pa;
3008 	u_char user;
3009 
3010 	PMAP_ASSERT_LOCKED(pmap);
3011 	rw_assert(&pvh_global_lock, RA_WLOCKED);
3012 	if (va == vector_page) {
3013 		pa = systempage.pv_pa;
3014 		m = NULL;
3015 	} else {
3016 		if ((m->oflags & VPO_UNMANAGED) == 0 && !vm_page_xbusied(m))
3017 			VM_OBJECT_ASSERT_LOCKED(m->object);
3018 		pa = VM_PAGE_TO_PHYS(m);
3019 	}
3020 
3021 	pl1pd = &pmap->pm_l1->l1_kva[L1_IDX(va)];
3022 	if ((va < VM_MAXUSER_ADDRESS) &&
3023 	    (*pl1pd & L1_TYPE_MASK) == L1_S_PROTO) {
3024 		(void)pmap_demote_section(pmap, va);
3025 	}
3026 
3027 	user = 0;
3028 	/*
3029 	 * Make sure userland mappings get the right permissions
3030 	 */
3031 	if (pmap != pmap_kernel() && va != vector_page)
3032 		user = 1;
3033 
3034 	nflags = 0;
3035 
3036 	if (prot & VM_PROT_WRITE)
3037 		nflags |= PVF_WRITE;
3038 	if ((flags & PMAP_ENTER_WIRED) != 0)
3039 		nflags |= PVF_WIRED;
3040 
3041 	PDEBUG(1, printf("pmap_enter: pmap = %08x, va = %08x, m = %08x, "
3042 	    "prot = %x, flags = %x\n", (uint32_t) pmap, va, (uint32_t) m,
3043 	    prot, flags));
3044 
3045 	if (pmap == pmap_kernel()) {
3046 		l2b = pmap_get_l2_bucket(pmap, va);
3047 		if (l2b == NULL)
3048 			l2b = pmap_grow_l2_bucket(pmap, va);
3049 	} else {
3050 do_l2b_alloc:
3051 		l2b = pmap_alloc_l2_bucket(pmap, va);
3052 		if (l2b == NULL) {
3053 			if ((flags & PMAP_ENTER_NOSLEEP) == 0) {
3054 				PMAP_UNLOCK(pmap);
3055 				rw_wunlock(&pvh_global_lock);
3056 				VM_WAIT;
3057 				rw_wlock(&pvh_global_lock);
3058 				PMAP_LOCK(pmap);
3059 				goto do_l2b_alloc;
3060 			}
3061 			return (KERN_RESOURCE_SHORTAGE);
3062 		}
3063 	}
3064 
3065 	pl1pd = &pmap->pm_l1->l1_kva[L1_IDX(va)];
3066 	if ((*pl1pd & L1_TYPE_MASK) == L1_S_PROTO)
3067 		panic("pmap_enter: attempt to enter on 1MB page, va: %#x", va);
3068 
3069 	ptep = &l2b->l2b_kva[l2pte_index(va)];
3070 
3071 	opte = *ptep;
3072 	npte = pa;
3073 	is_exec = is_refd = 0;
3074 
3075 	if (opte) {
3076 		if (l2pte_pa(opte) == pa) {
3077 			/*
3078 			 * We're changing the attrs of an existing mapping.
3079 			 */
3080 			if (m != NULL)
3081 				pmap_modify_pv(m, pmap, va,
3082 				    PVF_WRITE | PVF_WIRED, nflags);
3083 			is_exec |= PTE_BEEN_EXECD(opte);
3084 			is_refd |= PTE_BEEN_REFD(opte);
3085 			goto validate;
3086 		}
3087 		if ((om = PHYS_TO_VM_PAGE(l2pte_pa(opte)))) {
3088 			/*
3089 			 * Replacing an existing mapping with a new one.
3090 			 * It is part of our managed memory so we
3091 			 * must remove it from the PV list
3092 			 */
3093 			if ((pve = pmap_remove_pv(om, pmap, va))) {
3094 				is_exec |= PTE_BEEN_EXECD(opte);
3095 				is_refd |= PTE_BEEN_REFD(opte);
3096 
3097 				if (m && ((m->oflags & VPO_UNMANAGED)))
3098 					pmap_free_pv_entry(pmap, pve);
3099 			}
3100 		}
3101 
3102 	} else {
3103 		/*
3104 		 * Keep the stats up to date
3105 		 */
3106 		l2b->l2b_occupancy++;
3107 		pmap->pm_stats.resident_count++;
3108 	}
3109 
3110 	/*
3111 	 * Enter on the PV list if part of our managed memory.
3112 	 */
3113 	if ((m && !(m->oflags & VPO_UNMANAGED))) {
3114 		if ((!pve) && (pve = pmap_get_pv_entry(pmap, FALSE)) == NULL)
3115 			panic("pmap_enter: no pv entries");
3116 
3117 		KASSERT(va < kmi.clean_sva || va >= kmi.clean_eva,
3118 		("pmap_enter: managed mapping within the clean submap"));
3119 		KASSERT(pve != NULL, ("No pv"));
3120 		pmap_enter_pv(m, pve, pmap, va, nflags);
3121 	}
3122 
3123 validate:
3124 	/* Make the new PTE valid */
3125 	npte |= L2_S_PROTO;
3126 #ifdef SMP
3127 	npte |= L2_SHARED;
3128 #endif
3129 	/* Set defaults first - kernel read access */
3130 	npte |= L2_APX;
3131 	npte |= L2_S_PROT_R;
3132 	/* Set "referenced" flag */
3133 	npte |= L2_S_REF;
3134 
3135 	/* Now tune APs as desired */
3136 	if (user)
3137 		npte |= L2_S_PROT_U;
3138 	/*
3139 	 * If this is not a vector_page
3140 	 * then continue setting mapping parameters
3141 	 */
3142 	if (m != NULL) {
3143 		if ((m->oflags & VPO_UNMANAGED) == 0) {
3144 			if (prot & (VM_PROT_ALL)) {
3145 				vm_page_aflag_set(m, PGA_REFERENCED);
3146 			} else {
3147 				/*
3148 				 * Need to do page referenced emulation.
3149 				 */
3150 				npte &= ~L2_S_REF;
3151 			}
3152 		}
3153 
3154 		if (prot & VM_PROT_WRITE) {
3155 			if ((m->oflags & VPO_UNMANAGED) == 0) {
3156 				vm_page_aflag_set(m, PGA_WRITEABLE);
3157 				/*
3158 				 * XXX: Skip modified bit emulation for now.
3159 				 *	The emulation reveals problems
3160 				 *	that result in random failures
3161 				 *	during memory allocation on some
3162 				 *	platforms.
3163 				 *	Therefore, the page is marked RW
3164 				 *	immediately.
3165 				 */
3166 				npte &= ~(L2_APX);
3167 				vm_page_dirty(m);
3168 			} else
3169 				npte &= ~(L2_APX);
3170 		}
3171 		if (!(prot & VM_PROT_EXECUTE))
3172 			npte |= L2_XN;
3173 
3174 		if (m->md.pv_memattr != VM_MEMATTR_UNCACHEABLE)
3175 			npte |= pte_l2_s_cache_mode;
3176 	}
3177 
3178 	CTR5(KTR_PMAP,"enter: pmap:%p va:%x prot:%x pte:%x->%x",
3179 	    pmap, va, prot, opte, npte);
3180 	/*
3181 	 * If this is just a wiring change, the two PTEs will be
3182 	 * identical, so there's no need to update the page table.
3183 	 */
3184 	if (npte != opte) {
3185 		boolean_t is_cached = pmap_is_current(pmap);
3186 
3187 		*ptep = npte;
3188 		PTE_SYNC(ptep);
3189 		if (is_cached) {
3190 			/*
3191 			 * We only need to frob the cache/tlb if this pmap
3192 			 * is current
3193 			 */
3194 			if (L1_IDX(va) != L1_IDX(vector_page) &&
3195 			    l2pte_valid(npte)) {
3196 				/*
3197 				 * This mapping is likely to be accessed as
3198 				 * soon as we return to userland. Fix up the
3199 				 * L1 entry to avoid taking another
3200 				 * page/domain fault.
3201 				 */
3202 				l1pd = l2b->l2b_phys |
3203 				    L1_C_DOM(pmap->pm_domain) | L1_C_PROTO;
3204 				if (*pl1pd != l1pd) {
3205 					*pl1pd = l1pd;
3206 					PTE_SYNC(pl1pd);
3207 				}
3208 			}
3209 		}
3210 
3211 		if (is_exec)
3212 			cpu_tlb_flushID_SE(va);
3213 		else if (is_refd)
3214 			cpu_tlb_flushD_SE(va);
3215 		cpu_cpwait();
3216 	}
3217 
3218 	if ((pmap != pmap_kernel()) && (pmap == &curproc->p_vmspace->vm_pmap))
3219 		cpu_icache_sync_range(va, PAGE_SIZE);
3220 	return (KERN_SUCCESS);
3221 }
3222 
3223 /*
3224  * Maps a sequence of resident pages belonging to the same object.
3225  * The sequence begins with the given page m_start.  This page is
3226  * mapped at the given virtual address start.  Each subsequent page is
3227  * mapped at a virtual address that is offset from start by the same
3228  * amount as the page is offset from m_start within the object.  The
3229  * last page in the sequence is the page with the largest offset from
3230  * m_start that can be mapped at a virtual address less than the given
3231  * virtual address end.  Not every virtual page between start and end
3232  * is mapped; only those for which a resident page exists with the
3233  * corresponding offset from m_start are mapped.
3234  */
3235 void
3236 pmap_enter_object(pmap_t pmap, vm_offset_t start, vm_offset_t end,
3237     vm_page_t m_start, vm_prot_t prot)
3238 {
3239 	vm_offset_t va;
3240 	vm_page_t m;
3241 	vm_pindex_t diff, psize;
3242 
3243 	VM_OBJECT_ASSERT_LOCKED(m_start->object);
3244 
3245 	psize = atop(end - start);
3246 	m = m_start;
3247 	prot &= VM_PROT_READ | VM_PROT_EXECUTE;
3248 	rw_wlock(&pvh_global_lock);
3249 	PMAP_LOCK(pmap);
3250 	while (m != NULL && (diff = m->pindex - m_start->pindex) < psize) {
3251 		va = start + ptoa(diff);
3252 		if ((va & L1_S_OFFSET) == 0 && L2_NEXT_BUCKET(va) <= end &&
3253 		    m->psind == 1 && sp_enabled &&
3254 		    pmap_enter_section(pmap, va, m, prot))
3255 			m = &m[L1_S_SIZE / PAGE_SIZE - 1];
3256 		else
3257 			pmap_enter_locked(pmap, va, m, prot,
3258 			    PMAP_ENTER_NOSLEEP);
3259 		m = TAILQ_NEXT(m, listq);
3260 	}
3261 	PMAP_UNLOCK(pmap);
3262 	rw_wunlock(&pvh_global_lock);
3263 }
3264 
3265 /*
3266  * this code makes some *MAJOR* assumptions:
3267  * 1. Current pmap & pmap exists.
3268  * 2. Not wired.
3269  * 3. Read access.
3270  * 4. No page table pages.
3271  * but is *MUCH* faster than pmap_enter...
3272  */
3273 
3274 void
3275 pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot)
3276 {
3277 
3278 	prot &= VM_PROT_READ | VM_PROT_EXECUTE;
3279 	rw_wlock(&pvh_global_lock);
3280 	PMAP_LOCK(pmap);
3281 	pmap_enter_locked(pmap, va, m, prot, PMAP_ENTER_NOSLEEP);
3282 	PMAP_UNLOCK(pmap);
3283 	rw_wunlock(&pvh_global_lock);
3284 }
3285 
3286 /*
3287  *	Clear the wired attribute from the mappings for the specified range of
3288  *	addresses in the given pmap.  Every valid mapping within that range
3289  *	must have the wired attribute set.  In contrast, invalid mappings
3290  *	cannot have the wired attribute set, so they are ignored.
3291  *
3292  *	XXX Wired mappings of unmanaged pages cannot be counted by this pmap
3293  *	implementation.
3294  */
3295 void
3296 pmap_unwire(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
3297 {
3298 	struct l2_bucket *l2b;
3299 	struct md_page *pvh;
3300 	pd_entry_t l1pd;
3301 	pt_entry_t *ptep, pte;
3302 	pv_entry_t pv;
3303 	vm_offset_t next_bucket;
3304 	vm_paddr_t pa;
3305 	vm_page_t m;
3306 
3307 	rw_wlock(&pvh_global_lock);
3308 	PMAP_LOCK(pmap);
3309 	while (sva < eva) {
3310 		next_bucket = L2_NEXT_BUCKET(sva);
3311 		l1pd = pmap->pm_l1->l1_kva[L1_IDX(sva)];
3312 		if ((l1pd & L1_TYPE_MASK) == L1_S_PROTO) {
3313 			pa = l1pd & L1_S_FRAME;
3314 			m = PHYS_TO_VM_PAGE(pa);
3315 			KASSERT(m != NULL && (m->oflags & VPO_UNMANAGED) == 0,
3316 			    ("pmap_unwire: unmanaged 1mpage %p", m));
3317 			pvh = pa_to_pvh(pa);
3318 			pv = pmap_find_pv(pvh, pmap, trunc_1mpage(sva));
3319 			if ((pv->pv_flags & PVF_WIRED) == 0)
3320 				panic("pmap_unwire: pv %p isn't wired", pv);
3321 
3322 			/*
3323 			 * Are we unwiring the entire large page? If not,
3324 			 * demote the mapping and fall through.
3325 			 */
3326 			if (sva + L1_S_SIZE == next_bucket &&
3327 			    eva >= next_bucket) {
3328 				pv->pv_flags &= ~PVF_WIRED;
3329 				pmap->pm_stats.wired_count -= L2_PTE_NUM_TOTAL;
3330 				sva = next_bucket;
3331 				continue;
3332 			} else if (!pmap_demote_section(pmap, sva))
3333 				panic("pmap_unwire: demotion failed");
3334 		}
3335 		if (next_bucket > eva)
3336 			next_bucket = eva;
3337 		l2b = pmap_get_l2_bucket(pmap, sva);
3338 		if (l2b == NULL) {
3339 			sva = next_bucket;
3340 			continue;
3341 		}
3342 		for (ptep = &l2b->l2b_kva[l2pte_index(sva)]; sva < next_bucket;
3343 		    sva += PAGE_SIZE, ptep++) {
3344 			if ((pte = *ptep) == 0 ||
3345 			    (m = PHYS_TO_VM_PAGE(l2pte_pa(pte))) == NULL ||
3346 			    (m->oflags & VPO_UNMANAGED) != 0)
3347 				continue;
3348 			pv = pmap_find_pv(&m->md, pmap, sva);
3349 			if ((pv->pv_flags & PVF_WIRED) == 0)
3350 				panic("pmap_unwire: pv %p isn't wired", pv);
3351 			pv->pv_flags &= ~PVF_WIRED;
3352 			pmap->pm_stats.wired_count--;
3353 		}
3354 	}
3355 	rw_wunlock(&pvh_global_lock);
3356  	PMAP_UNLOCK(pmap);
3357 }
3358 
3359 
3360 /*
3361  *	Copy the range specified by src_addr/len
3362  *	from the source map to the range dst_addr/len
3363  *	in the destination map.
3364  *
3365  *	This routine is only advisory and need not do anything.
3366  */
3367 void
3368 pmap_copy(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr,
3369     vm_size_t len, vm_offset_t src_addr)
3370 {
3371 }
3372 
3373 
3374 /*
3375  *	Routine:	pmap_extract
3376  *	Function:
3377  *		Extract the physical page address associated
3378  *		with the given map/virtual_address pair.
3379  */
3380 vm_paddr_t
3381 pmap_extract(pmap_t pmap, vm_offset_t va)
3382 {
3383 	vm_paddr_t pa;
3384 
3385 	PMAP_LOCK(pmap);
3386 	pa = pmap_extract_locked(pmap, va);
3387 	PMAP_UNLOCK(pmap);
3388 	return (pa);
3389 }
3390 
3391 static vm_paddr_t
3392 pmap_extract_locked(pmap_t pmap, vm_offset_t va)
3393 {
3394 	struct l2_dtable *l2;
3395 	pd_entry_t l1pd;
3396 	pt_entry_t *ptep, pte;
3397 	vm_paddr_t pa;
3398 	u_int l1idx;
3399 
3400 	if (kernel_vm_end != 0 && pmap != kernel_pmap)
3401 		PMAP_ASSERT_LOCKED(pmap);
3402 	l1idx = L1_IDX(va);
3403 	l1pd = pmap->pm_l1->l1_kva[l1idx];
3404 	if (l1pte_section_p(l1pd)) {
3405 		/* XXX: what to do about the bits > 32 ? */
3406 		if (l1pd & L1_S_SUPERSEC)
3407 			pa = (l1pd & L1_SUP_FRAME) | (va & L1_SUP_OFFSET);
3408 		else
3409 			pa = (l1pd & L1_S_FRAME) | (va & L1_S_OFFSET);
3410 	} else {
3411 		/*
3412 		 * Note that we can't rely on the validity of the L1
3413 		 * descriptor as an indication that a mapping exists.
3414 		 * We have to look it up in the L2 dtable.
3415 		 */
3416 		l2 = pmap->pm_l2[L2_IDX(l1idx)];
3417 		if (l2 == NULL ||
3418 		    (ptep = l2->l2_bucket[L2_BUCKET(l1idx)].l2b_kva) == NULL)
3419 			return (0);
3420 		pte = ptep[l2pte_index(va)];
3421 		if (pte == 0)
3422 			return (0);
3423 		switch (pte & L2_TYPE_MASK) {
3424 		case L2_TYPE_L:
3425 			pa = (pte & L2_L_FRAME) | (va & L2_L_OFFSET);
3426 			break;
3427 		default:
3428 			pa = (pte & L2_S_FRAME) | (va & L2_S_OFFSET);
3429 			break;
3430 		}
3431 	}
3432 	return (pa);
3433 }
3434 
3435 /*
3436  * Atomically extract and hold the physical page with the given
3437  * pmap and virtual address pair if that mapping permits the given
3438  * protection.
3439  *
3440  */
3441 vm_page_t
3442 pmap_extract_and_hold(pmap_t pmap, vm_offset_t va, vm_prot_t prot)
3443 {
3444 	struct l2_dtable *l2;
3445 	pd_entry_t l1pd;
3446 	pt_entry_t *ptep, pte;
3447 	vm_paddr_t pa, paddr;
3448 	vm_page_t m = NULL;
3449 	u_int l1idx;
3450 	l1idx = L1_IDX(va);
3451 	paddr = 0;
3452 
3453 	PMAP_LOCK(pmap);
3454 retry:
3455 	l1pd = pmap->pm_l1->l1_kva[l1idx];
3456 	if (l1pte_section_p(l1pd)) {
3457 		/* XXX: what to do about the bits > 32 ? */
3458 		if (l1pd & L1_S_SUPERSEC)
3459 			pa = (l1pd & L1_SUP_FRAME) | (va & L1_SUP_OFFSET);
3460 		else
3461 			pa = (l1pd & L1_S_FRAME) | (va & L1_S_OFFSET);
3462 		if (vm_page_pa_tryrelock(pmap, pa & PG_FRAME, &paddr))
3463 			goto retry;
3464 		if (L1_S_WRITABLE(l1pd) || (prot & VM_PROT_WRITE) == 0) {
3465 			m = PHYS_TO_VM_PAGE(pa);
3466 			vm_page_hold(m);
3467 		}
3468 	} else {
3469 		/*
3470 		 * Note that we can't rely on the validity of the L1
3471 		 * descriptor as an indication that a mapping exists.
3472 		 * We have to look it up in the L2 dtable.
3473 		 */
3474 		l2 = pmap->pm_l2[L2_IDX(l1idx)];
3475 
3476 		if (l2 == NULL ||
3477 		    (ptep = l2->l2_bucket[L2_BUCKET(l1idx)].l2b_kva) == NULL) {
3478 			PMAP_UNLOCK(pmap);
3479 			return (NULL);
3480 		}
3481 
3482 		ptep = &ptep[l2pte_index(va)];
3483 		pte = *ptep;
3484 
3485 		if (pte == 0) {
3486 			PMAP_UNLOCK(pmap);
3487 			return (NULL);
3488 		} else if ((prot & VM_PROT_WRITE) && (pte & L2_APX)) {
3489 			PMAP_UNLOCK(pmap);
3490 			return (NULL);
3491 		} else {
3492 			switch (pte & L2_TYPE_MASK) {
3493 			case L2_TYPE_L:
3494 				panic("extract and hold section mapping");
3495 				break;
3496 			default:
3497 				pa = (pte & L2_S_FRAME) | (va & L2_S_OFFSET);
3498 				break;
3499 			}
3500 			if (vm_page_pa_tryrelock(pmap, pa & PG_FRAME, &paddr))
3501 				goto retry;
3502 			m = PHYS_TO_VM_PAGE(pa);
3503 			vm_page_hold(m);
3504 		}
3505 
3506 	}
3507 
3508 	PMAP_UNLOCK(pmap);
3509 	PA_UNLOCK_COND(paddr);
3510 	return (m);
3511 }
3512 
3513 /*
3514  * Initialize a preallocated and zeroed pmap structure,
3515  * such as one in a vmspace structure.
3516  */
3517 
3518 int
3519 pmap_pinit(pmap_t pmap)
3520 {
3521 	PDEBUG(1, printf("pmap_pinit: pmap = %08x\n", (uint32_t) pmap));
3522 
3523 	pmap_alloc_l1(pmap);
3524 	bzero(pmap->pm_l2, sizeof(pmap->pm_l2));
3525 
3526 	CPU_ZERO(&pmap->pm_active);
3527 
3528 	TAILQ_INIT(&pmap->pm_pvchunk);
3529 	bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
3530 	pmap->pm_stats.resident_count = 1;
3531 	if (vector_page < KERNBASE) {
3532 		pmap_enter(pmap, vector_page,
3533 		    PHYS_TO_VM_PAGE(systempage.pv_pa), VM_PROT_READ,
3534 		    PMAP_ENTER_WIRED, 0);
3535 	}
3536 	return (1);
3537 }
3538 
3539 
3540 /***************************************************
3541  * Superpage management routines.
3542  ***************************************************/
3543 
3544 static PMAP_INLINE struct pv_entry *
3545 pmap_pvh_remove(struct md_page *pvh, pmap_t pmap, vm_offset_t va)
3546 {
3547 	pv_entry_t pv;
3548 
3549 	rw_assert(&pvh_global_lock, RA_WLOCKED);
3550 
3551 	pv = pmap_find_pv(pvh, pmap, va);
3552 	if (pv != NULL)
3553 		TAILQ_REMOVE(&pvh->pv_list, pv, pv_list);
3554 
3555 	return (pv);
3556 }
3557 
3558 static void
3559 pmap_pvh_free(struct md_page *pvh, pmap_t pmap, vm_offset_t va)
3560 {
3561 	pv_entry_t pv;
3562 
3563 	pv = pmap_pvh_remove(pvh, pmap, va);
3564 	KASSERT(pv != NULL, ("pmap_pvh_free: pv not found"));
3565 	pmap_free_pv_entry(pmap, pv);
3566 }
3567 
3568 static boolean_t
3569 pmap_pv_insert_section(pmap_t pmap, vm_offset_t va, vm_paddr_t pa)
3570 {
3571 	struct md_page *pvh;
3572 	pv_entry_t pv;
3573 
3574 	rw_assert(&pvh_global_lock, RA_WLOCKED);
3575 	if (pv_entry_count < pv_entry_high_water &&
3576 	    (pv = pmap_get_pv_entry(pmap, TRUE)) != NULL) {
3577 		pv->pv_va = va;
3578 		pvh = pa_to_pvh(pa);
3579 		TAILQ_INSERT_TAIL(&pvh->pv_list, pv, pv_list);
3580 		return (TRUE);
3581 	} else
3582 		return (FALSE);
3583 }
3584 
3585 /*
3586  * Create the pv entries for each of the pages within a superpage.
3587  */
3588 static void
3589 pmap_pv_demote_section(pmap_t pmap, vm_offset_t va, vm_paddr_t pa)
3590 {
3591 	struct md_page *pvh;
3592 	pv_entry_t pve, pv;
3593 	vm_offset_t va_last;
3594 	vm_page_t m;
3595 
3596 	rw_assert(&pvh_global_lock, RA_WLOCKED);
3597 	KASSERT((pa & L1_S_OFFSET) == 0,
3598 	    ("pmap_pv_demote_section: pa is not 1mpage aligned"));
3599 
3600 	/*
3601 	 * Transfer the 1mpage's pv entry for this mapping to the first
3602 	 * page's pv list.
3603 	 */
3604 	pvh = pa_to_pvh(pa);
3605 	va = trunc_1mpage(va);
3606 	pv = pmap_pvh_remove(pvh, pmap, va);
3607 	KASSERT(pv != NULL, ("pmap_pv_demote_section: pv not found"));
3608 	m = PHYS_TO_VM_PAGE(pa);
3609 	TAILQ_INSERT_HEAD(&m->md.pv_list, pv, pv_list);
3610 	/* Instantiate the remaining pv entries. */
3611 	va_last = L2_NEXT_BUCKET(va) - PAGE_SIZE;
3612 	do {
3613 		m++;
3614 		KASSERT((m->oflags & VPO_UNMANAGED) == 0,
3615 		    ("pmap_pv_demote_section: page %p is not managed", m));
3616 		va += PAGE_SIZE;
3617 		pve = pmap_get_pv_entry(pmap, FALSE);
3618 		pmap_enter_pv(m, pve, pmap, va, pv->pv_flags);
3619 	} while (va < va_last);
3620 }
3621 
3622 static void
3623 pmap_pv_promote_section(pmap_t pmap, vm_offset_t va, vm_paddr_t pa)
3624 {
3625 	struct md_page *pvh;
3626 	pv_entry_t pv;
3627 	vm_offset_t va_last;
3628 	vm_page_t m;
3629 
3630 	rw_assert(&pvh_global_lock, RA_WLOCKED);
3631 	KASSERT((pa & L1_S_OFFSET) == 0,
3632 	    ("pmap_pv_promote_section: pa is not 1mpage aligned"));
3633 
3634 	/*
3635 	 * Transfer the first page's pv entry for this mapping to the
3636 	 * 1mpage's pv list.  Aside from avoiding the cost of a call
3637 	 * to get_pv_entry(), a transfer avoids the possibility that
3638 	 * get_pv_entry() calls pmap_pv_reclaim() and that pmap_pv_reclaim()
3639 	 * removes one of the mappings that is being promoted.
3640 	 */
3641 	m = PHYS_TO_VM_PAGE(pa);
3642 	va = trunc_1mpage(va);
3643 	pv = pmap_pvh_remove(&m->md, pmap, va);
3644 	KASSERT(pv != NULL, ("pmap_pv_promote_section: pv not found"));
3645 	pvh = pa_to_pvh(pa);
3646 	TAILQ_INSERT_TAIL(&pvh->pv_list, pv, pv_list);
3647 	/* Free the remaining pv entries in the newly mapped section pages */
3648 	va_last = L2_NEXT_BUCKET(va) - PAGE_SIZE;
3649 	do {
3650 		m++;
3651 		va += PAGE_SIZE;
3652 		/*
3653 		 * Don't care the flags, first pv contains sufficient
3654 		 * information for all of the pages so nothing is really lost.
3655 		 */
3656 		pmap_pvh_free(&m->md, pmap, va);
3657 	} while (va < va_last);
3658 }
3659 
3660 /*
3661  * Tries to create a 1MB page mapping.  Returns TRUE if successful and
3662  * FALSE otherwise.  Fails if (1) page is unmanageg, kernel pmap or vectors
3663  * page, (2) a mapping already exists at the specified virtual address, or
3664  * (3) a pv entry cannot be allocated without reclaiming another pv entry.
3665  */
3666 static boolean_t
3667 pmap_enter_section(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot)
3668 {
3669 	pd_entry_t *pl1pd;
3670 	vm_offset_t pa;
3671 	struct l2_bucket *l2b;
3672 
3673 	rw_assert(&pvh_global_lock, RA_WLOCKED);
3674 	PMAP_ASSERT_LOCKED(pmap);
3675 
3676 	/* Skip kernel, vectors page and unmanaged mappings */
3677 	if ((pmap == pmap_kernel()) || (L1_IDX(va) == L1_IDX(vector_page)) ||
3678 	    ((m->oflags & VPO_UNMANAGED) != 0)) {
3679 		CTR2(KTR_PMAP, "pmap_enter_section: failure for va %#lx"
3680 		    " in pmap %p", va, pmap);
3681 		return (FALSE);
3682 	}
3683 	/*
3684 	 * Check whether this is a valid section superpage entry or
3685 	 * there is a l2_bucket associated with that L1 page directory.
3686 	 */
3687 	va = trunc_1mpage(va);
3688 	pl1pd = &pmap->pm_l1->l1_kva[L1_IDX(va)];
3689 	l2b = pmap_get_l2_bucket(pmap, va);
3690 	if ((*pl1pd & L1_S_PROTO) || (l2b != NULL)) {
3691 		CTR2(KTR_PMAP, "pmap_enter_section: failure for va %#lx"
3692 		    " in pmap %p", va, pmap);
3693 		return (FALSE);
3694 	}
3695 	pa = VM_PAGE_TO_PHYS(m);
3696 	/*
3697 	 * Abort this mapping if its PV entry could not be created.
3698 	 */
3699 	if (!pmap_pv_insert_section(pmap, va, VM_PAGE_TO_PHYS(m))) {
3700 		CTR2(KTR_PMAP, "pmap_enter_section: failure for va %#lx"
3701 		    " in pmap %p", va, pmap);
3702 		return (FALSE);
3703 	}
3704 	/*
3705 	 * Increment counters.
3706 	 */
3707 	pmap->pm_stats.resident_count += L2_PTE_NUM_TOTAL;
3708 	/*
3709 	 * Despite permissions, mark the superpage read-only.
3710 	 */
3711 	prot &= ~VM_PROT_WRITE;
3712 	/*
3713 	 * Map the superpage.
3714 	 */
3715 	pmap_map_section(pmap, va, pa, prot, FALSE);
3716 
3717 	pmap_section_mappings++;
3718 	CTR2(KTR_PMAP, "pmap_enter_section: success for va %#lx"
3719 	    " in pmap %p", va, pmap);
3720 	return (TRUE);
3721 }
3722 
3723 /*
3724  * pmap_remove_section: do the things to unmap a superpage in a process
3725  */
3726 static void
3727 pmap_remove_section(pmap_t pmap, vm_offset_t sva)
3728 {
3729 	struct md_page *pvh;
3730 	struct l2_bucket *l2b;
3731 	pd_entry_t *pl1pd, l1pd;
3732 	vm_offset_t eva, va;
3733 	vm_page_t m;
3734 
3735 	PMAP_ASSERT_LOCKED(pmap);
3736 	if ((pmap == pmap_kernel()) || (L1_IDX(sva) == L1_IDX(vector_page)))
3737 		return;
3738 
3739 	KASSERT((sva & L1_S_OFFSET) == 0,
3740 	    ("pmap_remove_section: sva is not 1mpage aligned"));
3741 
3742 	pl1pd = &pmap->pm_l1->l1_kva[L1_IDX(sva)];
3743 	l1pd = *pl1pd;
3744 
3745 	m = PHYS_TO_VM_PAGE(l1pd & L1_S_FRAME);
3746 	KASSERT((m != NULL && ((m->oflags & VPO_UNMANAGED) == 0)),
3747 	    ("pmap_remove_section: no corresponding vm_page or "
3748 	    "page unmanaged"));
3749 
3750 	pmap->pm_stats.resident_count -= L2_PTE_NUM_TOTAL;
3751 	pvh = pa_to_pvh(l1pd & L1_S_FRAME);
3752 	pmap_pvh_free(pvh, pmap, sva);
3753 	eva = L2_NEXT_BUCKET(sva);
3754 	for (va = sva, m = PHYS_TO_VM_PAGE(l1pd & L1_S_FRAME);
3755 	    va < eva; va += PAGE_SIZE, m++) {
3756 		/*
3757 		 * Mark base pages referenced but skip marking them dirty.
3758 		 * If the superpage is writeable, hence all base pages were
3759 		 * already marked as dirty in pmap_fault_fixup() before
3760 		 * promotion. Reference bit however, might not have been set
3761 		 * for each base page when the superpage was created at once,
3762 		 * not as a result of promotion.
3763 		 */
3764 		if (L1_S_REFERENCED(l1pd))
3765 			vm_page_aflag_set(m, PGA_REFERENCED);
3766 		if (TAILQ_EMPTY(&m->md.pv_list) &&
3767 		    TAILQ_EMPTY(&pvh->pv_list))
3768 			vm_page_aflag_clear(m, PGA_WRITEABLE);
3769 	}
3770 
3771 	l2b = pmap_get_l2_bucket(pmap, sva);
3772 	if (l2b != NULL) {
3773 		KASSERT(l2b->l2b_occupancy == L2_PTE_NUM_TOTAL,
3774 		    ("pmap_remove_section: l2_bucket occupancy error"));
3775 		pmap_free_l2_bucket(pmap, l2b, L2_PTE_NUM_TOTAL);
3776 	}
3777 	/* Now invalidate L1 slot */
3778 	*pl1pd = 0;
3779 	PTE_SYNC(pl1pd);
3780 	if (L1_S_EXECUTABLE(l1pd))
3781 		cpu_tlb_flushID_SE(sva);
3782 	else
3783 		cpu_tlb_flushD_SE(sva);
3784 	cpu_cpwait();
3785 }
3786 
3787 /*
3788  * Tries to promote the 256, contiguous 4KB page mappings that are
3789  * within a single l2_bucket to a single 1MB section mapping.
3790  * For promotion to occur, two conditions must be met: (1) the 4KB page
3791  * mappings must map aligned, contiguous physical memory and (2) the 4KB page
3792  * mappings must have identical characteristics.
3793  */
3794 static void
3795 pmap_promote_section(pmap_t pmap, vm_offset_t va)
3796 {
3797 	pt_entry_t *firstptep, firstpte, oldpte, pa, *pte;
3798 	vm_page_t m, oldm;
3799 	vm_offset_t first_va, old_va;
3800 	struct l2_bucket *l2b = NULL;
3801 	vm_prot_t prot;
3802 	struct pv_entry *pve, *first_pve;
3803 
3804 	PMAP_ASSERT_LOCKED(pmap);
3805 
3806 	prot = VM_PROT_ALL;
3807 	/*
3808 	 * Skip promoting kernel pages. This is justified by following:
3809 	 * 1. Kernel is already mapped using section mappings in each pmap
3810 	 * 2. Managed mappings within the kernel are not to be promoted anyway
3811 	 */
3812 	if (pmap == pmap_kernel()) {
3813 		pmap_section_p_failures++;
3814 		CTR2(KTR_PMAP, "pmap_promote_section: failure for va %#x"
3815 		    " in pmap %p", va, pmap);
3816 		return;
3817 	}
3818 	/* Do not attemp to promote vectors pages */
3819 	if (L1_IDX(va) == L1_IDX(vector_page)) {
3820 		pmap_section_p_failures++;
3821 		CTR2(KTR_PMAP, "pmap_promote_section: failure for va %#x"
3822 		    " in pmap %p", va, pmap);
3823 		return;
3824 	}
3825 	/*
3826 	 * Examine the first PTE in the specified l2_bucket. Abort if this PTE
3827 	 * is either invalid, unused, or does not map the first 4KB physical
3828 	 * page within 1MB page.
3829 	 */
3830 	first_va = trunc_1mpage(va);
3831 	l2b = pmap_get_l2_bucket(pmap, first_va);
3832 	KASSERT(l2b != NULL, ("pmap_promote_section: trying to promote "
3833 	    "not existing l2 bucket"));
3834 	firstptep = &l2b->l2b_kva[0];
3835 
3836 	firstpte = *firstptep;
3837 	if ((l2pte_pa(firstpte) & L1_S_OFFSET) != 0) {
3838 		pmap_section_p_failures++;
3839 		CTR2(KTR_PMAP, "pmap_promote_section: failure for va %#x"
3840 		    " in pmap %p", va, pmap);
3841 		return;
3842 	}
3843 
3844 	if ((firstpte & (L2_S_PROTO | L2_S_REF)) != (L2_S_PROTO | L2_S_REF)) {
3845 		pmap_section_p_failures++;
3846 		CTR2(KTR_PMAP, "pmap_promote_section: failure for va %#x"
3847 		    " in pmap %p", va, pmap);
3848 		return;
3849 	}
3850 	/*
3851 	 * ARM uses pv_entry to mark particular mapping WIRED so don't promote
3852 	 * unmanaged pages since it is impossible to determine, whether the
3853 	 * page is wired or not if there is no corresponding pv_entry.
3854 	 */
3855 	m = PHYS_TO_VM_PAGE(l2pte_pa(firstpte));
3856 	if (m && ((m->oflags & VPO_UNMANAGED) != 0)) {
3857 		pmap_section_p_failures++;
3858 		CTR2(KTR_PMAP, "pmap_promote_section: failure for va %#x"
3859 		    " in pmap %p", va, pmap);
3860 		return;
3861 	}
3862 	first_pve = pmap_find_pv(&m->md, pmap, first_va);
3863 	/*
3864 	 * PTE is modified only on write due to modified bit
3865 	 * emulation. If the entry is referenced and writable
3866 	 * then it is modified and we don't clear write enable.
3867 	 * Otherwise, writing is disabled in PTE anyway and
3868 	 * we just configure protections for the section mapping
3869 	 * that is going to be created.
3870 	 */
3871 	if ((first_pve->pv_flags & PVF_WRITE) != 0) {
3872 		if (!L2_S_WRITABLE(firstpte)) {
3873 			first_pve->pv_flags &= ~PVF_WRITE;
3874 			prot &= ~VM_PROT_WRITE;
3875 		}
3876 	} else
3877 		prot &= ~VM_PROT_WRITE;
3878 
3879 	if (!L2_S_EXECUTABLE(firstpte))
3880 		prot &= ~VM_PROT_EXECUTE;
3881 
3882 	/*
3883 	 * Examine each of the other PTEs in the specified l2_bucket.
3884 	 * Abort if this PTE maps an unexpected 4KB physical page or
3885 	 * does not have identical characteristics to the first PTE.
3886 	 */
3887 	pa = l2pte_pa(firstpte) + ((L2_PTE_NUM_TOTAL - 1) * PAGE_SIZE);
3888 	old_va = L2_NEXT_BUCKET(first_va) - PAGE_SIZE;
3889 
3890 	for (pte = (firstptep + L2_PTE_NUM_TOTAL - 1); pte > firstptep; pte--) {
3891 		oldpte = *pte;
3892 		if (l2pte_pa(oldpte) != pa) {
3893 			pmap_section_p_failures++;
3894 			CTR2(KTR_PMAP, "pmap_promote_section: failure for "
3895 			    "va %#x in pmap %p", va, pmap);
3896 			return;
3897 		}
3898 		if ((oldpte & L2_S_PROMOTE) != (firstpte & L2_S_PROMOTE)) {
3899 			pmap_section_p_failures++;
3900 			CTR2(KTR_PMAP, "pmap_promote_section: failure for "
3901 			    "va %#x in pmap %p", va, pmap);
3902 			return;
3903 		}
3904 		oldm = PHYS_TO_VM_PAGE(l2pte_pa(oldpte));
3905 		if (oldm && ((oldm->oflags & VPO_UNMANAGED) != 0)) {
3906 			pmap_section_p_failures++;
3907 			CTR2(KTR_PMAP, "pmap_promote_section: failure for "
3908 			    "va %#x in pmap %p", va, pmap);
3909 			return;
3910 		}
3911 
3912 		pve = pmap_find_pv(&oldm->md, pmap, old_va);
3913 		if (pve == NULL) {
3914 			pmap_section_p_failures++;
3915 			CTR2(KTR_PMAP, "pmap_promote_section: failure for "
3916 			    "va %#x old_va  %x - no pve", va, old_va);
3917 			return;
3918 		}
3919 
3920 		if (!L2_S_WRITABLE(oldpte) && (pve->pv_flags & PVF_WRITE))
3921 			pve->pv_flags &= ~PVF_WRITE;
3922 		if (pve->pv_flags != first_pve->pv_flags) {
3923 			pmap_section_p_failures++;
3924 			CTR2(KTR_PMAP, "pmap_promote_section: failure for "
3925 			    "va %#x in pmap %p", va, pmap);
3926 			return;
3927 		}
3928 
3929 		old_va -= PAGE_SIZE;
3930 		pa -= PAGE_SIZE;
3931 	}
3932 	/*
3933 	 * Promote the pv entries.
3934 	 */
3935 	pmap_pv_promote_section(pmap, first_va, l2pte_pa(firstpte));
3936 	/*
3937 	 * Map the superpage.
3938 	 */
3939 	pmap_map_section(pmap, first_va, l2pte_pa(firstpte), prot, TRUE);
3940 	/*
3941 	 * Invalidate all possible TLB mappings for small
3942 	 * pages within the newly created superpage.
3943 	 * Rely on the first PTE's attributes since they
3944 	 * have to be consistent across all of the base pages
3945 	 * within the superpage. If page is not executable it
3946 	 * is at least referenced.
3947 	 * The fastest way to do that is to invalidate whole
3948 	 * TLB at once instead of executing 256 CP15 TLB
3949 	 * invalidations by single entry. TLBs usually maintain
3950 	 * several dozen entries so loss of unrelated entries is
3951 	 * still a less agresive approach.
3952 	 */
3953 	if (L2_S_EXECUTABLE(firstpte))
3954 		cpu_tlb_flushID();
3955 	else
3956 		cpu_tlb_flushD();
3957 	cpu_cpwait();
3958 
3959 	pmap_section_promotions++;
3960 	CTR2(KTR_PMAP, "pmap_promote_section: success for va %#x"
3961 	    " in pmap %p", first_va, pmap);
3962 }
3963 
3964 /*
3965  * Fills a l2_bucket with mappings to consecutive physical pages.
3966  */
3967 static void
3968 pmap_fill_l2b(struct l2_bucket *l2b, pt_entry_t newpte)
3969 {
3970 	pt_entry_t *ptep;
3971 	int i;
3972 
3973 	for (i = 0; i < L2_PTE_NUM_TOTAL; i++) {
3974 		ptep = &l2b->l2b_kva[i];
3975 		*ptep = newpte;
3976 		PTE_SYNC(ptep);
3977 
3978 		newpte += PAGE_SIZE;
3979 	}
3980 
3981 	l2b->l2b_occupancy = L2_PTE_NUM_TOTAL;
3982 }
3983 
3984 /*
3985  * Tries to demote a 1MB section mapping. If demotion fails, the
3986  * 1MB section mapping is invalidated.
3987  */
3988 static boolean_t
3989 pmap_demote_section(pmap_t pmap, vm_offset_t va)
3990 {
3991 	struct l2_bucket *l2b;
3992 	struct pv_entry *l1pdpve;
3993 	struct md_page *pvh;
3994 	pd_entry_t *pl1pd, l1pd, newl1pd;
3995 	pt_entry_t *firstptep, newpte;
3996 	vm_offset_t pa;
3997 	vm_page_t m;
3998 
3999 	PMAP_ASSERT_LOCKED(pmap);
4000 	/*
4001 	 * According to assumptions described in pmap_promote_section,
4002 	 * kernel is and always should be mapped using 1MB section mappings.
4003 	 * What more, managed kernel pages were not to be promoted.
4004 	 */
4005 	KASSERT(pmap != pmap_kernel() && L1_IDX(va) != L1_IDX(vector_page),
4006 	    ("pmap_demote_section: forbidden section mapping"));
4007 
4008 	va = trunc_1mpage(va);
4009 	pl1pd = &pmap->pm_l1->l1_kva[L1_IDX(va)];
4010 	l1pd = *pl1pd;
4011 	KASSERT((l1pd & L1_TYPE_MASK) == L1_S_PROTO,
4012 	    ("pmap_demote_section: not section or invalid section"));
4013 
4014 	pa = l1pd & L1_S_FRAME;
4015 	m = PHYS_TO_VM_PAGE(pa);
4016 	KASSERT((m != NULL && (m->oflags & VPO_UNMANAGED) == 0),
4017 	    ("pmap_demote_section: no vm_page for selected superpage or"
4018 	     "unmanaged"));
4019 
4020 	pvh = pa_to_pvh(pa);
4021 	l1pdpve = pmap_find_pv(pvh, pmap, va);
4022 	KASSERT(l1pdpve != NULL, ("pmap_demote_section: no pv entry for "
4023 	    "managed page"));
4024 
4025 	l2b = pmap_get_l2_bucket(pmap, va);
4026 	if (l2b == NULL) {
4027 		KASSERT((l1pdpve->pv_flags & PVF_WIRED) == 0,
4028 		    ("pmap_demote_section: No l2_bucket for wired mapping"));
4029 		/*
4030 		 * Invalidate the 1MB section mapping and return
4031 		 * "failure" if the mapping was never accessed or the
4032 		 * allocation of the new l2_bucket fails.
4033 		 */
4034 		if (!L1_S_REFERENCED(l1pd) ||
4035 		    (l2b = pmap_alloc_l2_bucket(pmap, va)) == NULL) {
4036 			/* Unmap and invalidate superpage. */
4037 			pmap_remove_section(pmap, trunc_1mpage(va));
4038 			CTR2(KTR_PMAP, "pmap_demote_section: failure for "
4039 			    "va %#x in pmap %p", va, pmap);
4040 			return (FALSE);
4041 		}
4042 	}
4043 
4044 	/*
4045 	 * Now we should have corresponding l2_bucket available.
4046 	 * Let's process it to recreate 256 PTEs for each base page
4047 	 * within superpage.
4048 	 */
4049 	newpte = pa | L1_S_DEMOTE(l1pd);
4050 	if (m->md.pv_memattr != VM_MEMATTR_UNCACHEABLE)
4051 		newpte |= pte_l2_s_cache_mode;
4052 
4053 	/*
4054 	 * If the l2_bucket is new, initialize it.
4055 	 */
4056 	if (l2b->l2b_occupancy == 0)
4057 		pmap_fill_l2b(l2b, newpte);
4058 	else {
4059 		firstptep = &l2b->l2b_kva[0];
4060 		KASSERT(l2pte_pa(*firstptep) == (pa),
4061 		    ("pmap_demote_section: firstpte and newpte map different "
4062 		     "physical addresses"));
4063 		/*
4064 		 * If the mapping has changed attributes, update the page table
4065 		 * entries.
4066 		 */
4067 		if ((*firstptep & L2_S_PROMOTE) != (L1_S_DEMOTE(l1pd)))
4068 			pmap_fill_l2b(l2b, newpte);
4069 	}
4070 	/* Demote PV entry */
4071 	pmap_pv_demote_section(pmap, va, pa);
4072 
4073 	/* Now fix-up L1 */
4074 	newl1pd = l2b->l2b_phys | L1_C_DOM(pmap->pm_domain) | L1_C_PROTO;
4075 	*pl1pd = newl1pd;
4076 	PTE_SYNC(pl1pd);
4077 	/* Invalidate old TLB mapping */
4078 	if (L1_S_EXECUTABLE(l1pd))
4079 		cpu_tlb_flushID_SE(va);
4080 	else if (L1_S_REFERENCED(l1pd))
4081 		cpu_tlb_flushD_SE(va);
4082 	cpu_cpwait();
4083 
4084 	pmap_section_demotions++;
4085 	CTR2(KTR_PMAP, "pmap_demote_section: success for va %#x"
4086 	    " in pmap %p", va, pmap);
4087 	return (TRUE);
4088 }
4089 
4090 /***************************************************
4091  * page management routines.
4092  ***************************************************/
4093 
4094 /*
4095  * We are in a serious low memory condition.  Resort to
4096  * drastic measures to free some pages so we can allocate
4097  * another pv entry chunk.
4098  */
4099 static vm_page_t
4100 pmap_pv_reclaim(pmap_t locked_pmap)
4101 {
4102 	struct pch newtail;
4103 	struct pv_chunk *pc;
4104 	struct l2_bucket *l2b = NULL;
4105 	pmap_t pmap;
4106 	pd_entry_t *pl1pd;
4107 	pt_entry_t *ptep;
4108 	pv_entry_t pv;
4109 	vm_offset_t va;
4110 	vm_page_t free, m, m_pc;
4111 	uint32_t inuse;
4112 	int bit, field, freed, idx;
4113 
4114 	PMAP_ASSERT_LOCKED(locked_pmap);
4115 	pmap = NULL;
4116 	free = m_pc = NULL;
4117 	TAILQ_INIT(&newtail);
4118 	while ((pc = TAILQ_FIRST(&pv_chunks)) != NULL && (pv_vafree == 0 ||
4119 	    free == NULL)) {
4120 		TAILQ_REMOVE(&pv_chunks, pc, pc_lru);
4121 		if (pmap != pc->pc_pmap) {
4122 			if (pmap != NULL) {
4123 				cpu_tlb_flushID();
4124 				cpu_cpwait();
4125 				if (pmap != locked_pmap)
4126 					PMAP_UNLOCK(pmap);
4127 			}
4128 			pmap = pc->pc_pmap;
4129 			/* Avoid deadlock and lock recursion. */
4130 			if (pmap > locked_pmap)
4131 				PMAP_LOCK(pmap);
4132 			else if (pmap != locked_pmap && !PMAP_TRYLOCK(pmap)) {
4133 				pmap = NULL;
4134 				TAILQ_INSERT_TAIL(&newtail, pc, pc_lru);
4135 				continue;
4136 			}
4137 		}
4138 
4139 		/*
4140 		 * Destroy every non-wired, 4 KB page mapping in the chunk.
4141 		 */
4142 		freed = 0;
4143 		for (field = 0; field < _NPCM; field++) {
4144 			for (inuse = ~pc->pc_map[field] & pc_freemask[field];
4145 			    inuse != 0; inuse &= ~(1UL << bit)) {
4146 				bit = ffs(inuse) - 1;
4147 				idx = field * sizeof(inuse) * NBBY + bit;
4148 				pv = &pc->pc_pventry[idx];
4149 				va = pv->pv_va;
4150 
4151 				pl1pd = &pmap->pm_l1->l1_kva[L1_IDX(va)];
4152 				if ((*pl1pd & L1_TYPE_MASK) == L1_S_PROTO)
4153 					continue;
4154 				if (pv->pv_flags & PVF_WIRED)
4155 					continue;
4156 
4157 				l2b = pmap_get_l2_bucket(pmap, va);
4158 				KASSERT(l2b != NULL, ("No l2 bucket"));
4159 				ptep = &l2b->l2b_kva[l2pte_index(va)];
4160 				m = PHYS_TO_VM_PAGE(l2pte_pa(*ptep));
4161 				KASSERT((vm_offset_t)m >= KERNBASE,
4162 				    ("Trying to access non-existent page "
4163 				     "va %x pte %x", va, *ptep));
4164 				*ptep = 0;
4165 				PTE_SYNC(ptep);
4166 				TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
4167 				if (TAILQ_EMPTY(&m->md.pv_list))
4168 					vm_page_aflag_clear(m, PGA_WRITEABLE);
4169 				pc->pc_map[field] |= 1UL << bit;
4170 				freed++;
4171 			}
4172 		}
4173 
4174 		if (freed == 0) {
4175 			TAILQ_INSERT_TAIL(&newtail, pc, pc_lru);
4176 			continue;
4177 		}
4178 		/* Every freed mapping is for a 4 KB page. */
4179 		pmap->pm_stats.resident_count -= freed;
4180 		PV_STAT(pv_entry_frees += freed);
4181 		PV_STAT(pv_entry_spare += freed);
4182 		pv_entry_count -= freed;
4183 		TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
4184 		for (field = 0; field < _NPCM; field++)
4185 			if (pc->pc_map[field] != pc_freemask[field]) {
4186 				TAILQ_INSERT_HEAD(&pmap->pm_pvchunk, pc,
4187 				    pc_list);
4188 				TAILQ_INSERT_TAIL(&newtail, pc, pc_lru);
4189 
4190 				/*
4191 				 * One freed pv entry in locked_pmap is
4192 				 * sufficient.
4193 				 */
4194 				if (pmap == locked_pmap)
4195 					goto out;
4196 				break;
4197 			}
4198 		if (field == _NPCM) {
4199 			PV_STAT(pv_entry_spare -= _NPCPV);
4200 			PV_STAT(pc_chunk_count--);
4201 			PV_STAT(pc_chunk_frees++);
4202 			/* Entire chunk is free; return it. */
4203 			m_pc = PHYS_TO_VM_PAGE(pmap_kextract((vm_offset_t)pc));
4204 			pmap_qremove((vm_offset_t)pc, 1);
4205 			pmap_ptelist_free(&pv_vafree, (vm_offset_t)pc);
4206 			break;
4207 		}
4208 	}
4209 out:
4210 	TAILQ_CONCAT(&pv_chunks, &newtail, pc_lru);
4211 	if (pmap != NULL) {
4212 		cpu_tlb_flushID();
4213 		cpu_cpwait();
4214 		if (pmap != locked_pmap)
4215 			PMAP_UNLOCK(pmap);
4216 	}
4217 	return (m_pc);
4218 }
4219 
4220 /*
4221  * free the pv_entry back to the free list
4222  */
4223 static void
4224 pmap_free_pv_entry(pmap_t pmap, pv_entry_t pv)
4225 {
4226 	struct pv_chunk *pc;
4227 	int bit, field, idx;
4228 
4229 	rw_assert(&pvh_global_lock, RA_WLOCKED);
4230 	PMAP_ASSERT_LOCKED(pmap);
4231 	PV_STAT(pv_entry_frees++);
4232 	PV_STAT(pv_entry_spare++);
4233 	pv_entry_count--;
4234 	pc = pv_to_chunk(pv);
4235 	idx = pv - &pc->pc_pventry[0];
4236 	field = idx / (sizeof(u_long) * NBBY);
4237 	bit = idx % (sizeof(u_long) * NBBY);
4238 	pc->pc_map[field] |= 1ul << bit;
4239 	for (idx = 0; idx < _NPCM; idx++)
4240 		if (pc->pc_map[idx] != pc_freemask[idx]) {
4241 			/*
4242 			 * 98% of the time, pc is already at the head of the
4243 			 * list.  If it isn't already, move it to the head.
4244 			 */
4245 			if (__predict_false(TAILQ_FIRST(&pmap->pm_pvchunk) !=
4246 			    pc)) {
4247 				TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
4248 				TAILQ_INSERT_HEAD(&pmap->pm_pvchunk, pc,
4249 				    pc_list);
4250 			}
4251 			return;
4252 		}
4253 	TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
4254 	pmap_free_pv_chunk(pc);
4255 }
4256 
4257 static void
4258 pmap_free_pv_chunk(struct pv_chunk *pc)
4259 {
4260 	vm_page_t m;
4261 
4262 	TAILQ_REMOVE(&pv_chunks, pc, pc_lru);
4263 	PV_STAT(pv_entry_spare -= _NPCPV);
4264 	PV_STAT(pc_chunk_count--);
4265 	PV_STAT(pc_chunk_frees++);
4266 	/* entire chunk is free, return it */
4267 	m = PHYS_TO_VM_PAGE(pmap_kextract((vm_offset_t)pc));
4268 	pmap_qremove((vm_offset_t)pc, 1);
4269 	vm_page_unwire(m, PQ_INACTIVE);
4270 	vm_page_free(m);
4271 	pmap_ptelist_free(&pv_vafree, (vm_offset_t)pc);
4272 
4273 }
4274 
4275 static pv_entry_t
4276 pmap_get_pv_entry(pmap_t pmap, boolean_t try)
4277 {
4278 	static const struct timeval printinterval = { 60, 0 };
4279 	static struct timeval lastprint;
4280 	struct pv_chunk *pc;
4281 	pv_entry_t pv;
4282 	vm_page_t m;
4283 	int bit, field, idx;
4284 
4285 	rw_assert(&pvh_global_lock, RA_WLOCKED);
4286 	PMAP_ASSERT_LOCKED(pmap);
4287 	PV_STAT(pv_entry_allocs++);
4288 	pv_entry_count++;
4289 
4290 	if (pv_entry_count > pv_entry_high_water)
4291 		if (ratecheck(&lastprint, &printinterval))
4292 			printf("%s: Approaching the limit on PV entries.\n",
4293 			    __func__);
4294 retry:
4295 	pc = TAILQ_FIRST(&pmap->pm_pvchunk);
4296 	if (pc != NULL) {
4297 		for (field = 0; field < _NPCM; field++) {
4298 			if (pc->pc_map[field]) {
4299 				bit = ffs(pc->pc_map[field]) - 1;
4300 				break;
4301 			}
4302 		}
4303 		if (field < _NPCM) {
4304 			idx = field * sizeof(pc->pc_map[field]) * NBBY + bit;
4305 			pv = &pc->pc_pventry[idx];
4306 			pc->pc_map[field] &= ~(1ul << bit);
4307 			/* If this was the last item, move it to tail */
4308 			for (field = 0; field < _NPCM; field++)
4309 				if (pc->pc_map[field] != 0) {
4310 					PV_STAT(pv_entry_spare--);
4311 					return (pv);	/* not full, return */
4312 				}
4313 			TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
4314 			TAILQ_INSERT_TAIL(&pmap->pm_pvchunk, pc, pc_list);
4315 			PV_STAT(pv_entry_spare--);
4316 			return (pv);
4317 		}
4318 	}
4319 	/*
4320 	 * Access to the ptelist "pv_vafree" is synchronized by the pvh
4321 	 * global lock.  If "pv_vafree" is currently non-empty, it will
4322 	 * remain non-empty until pmap_ptelist_alloc() completes.
4323 	 */
4324 	if (pv_vafree == 0 || (m = vm_page_alloc(NULL, 0, VM_ALLOC_NORMAL |
4325 	    VM_ALLOC_NOOBJ | VM_ALLOC_WIRED)) == NULL) {
4326 		if (try) {
4327 			pv_entry_count--;
4328 			PV_STAT(pc_chunk_tryfail++);
4329 			return (NULL);
4330 		}
4331 		m = pmap_pv_reclaim(pmap);
4332 		if (m == NULL)
4333 			goto retry;
4334 	}
4335 	PV_STAT(pc_chunk_count++);
4336 	PV_STAT(pc_chunk_allocs++);
4337 	pc = (struct pv_chunk *)pmap_ptelist_alloc(&pv_vafree);
4338 	pmap_qenter((vm_offset_t)pc, &m, 1);
4339 	pc->pc_pmap = pmap;
4340 	pc->pc_map[0] = pc_freemask[0] & ~1ul;	/* preallocated bit 0 */
4341 	for (field = 1; field < _NPCM; field++)
4342 		pc->pc_map[field] = pc_freemask[field];
4343 	TAILQ_INSERT_TAIL(&pv_chunks, pc, pc_lru);
4344 	pv = &pc->pc_pventry[0];
4345 	TAILQ_INSERT_HEAD(&pmap->pm_pvchunk, pc, pc_list);
4346 	PV_STAT(pv_entry_spare += _NPCPV - 1);
4347 	return (pv);
4348 }
4349 
4350 /*
4351  *	Remove the given range of addresses from the specified map.
4352  *
4353  *	It is assumed that the start and end are properly
4354  *	rounded to the page size.
4355  */
4356 #define	PMAP_REMOVE_CLEAN_LIST_SIZE	3
4357 void
4358 pmap_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
4359 {
4360 	struct l2_bucket *l2b;
4361 	vm_offset_t next_bucket;
4362 	pd_entry_t l1pd;
4363 	pt_entry_t *ptep;
4364 	u_int total;
4365 	u_int mappings, is_exec, is_refd;
4366 	int flushall = 0;
4367 
4368 
4369 	/*
4370 	 * we lock in the pmap => pv_head direction
4371 	 */
4372 
4373 	rw_wlock(&pvh_global_lock);
4374 	PMAP_LOCK(pmap);
4375 	total = 0;
4376 	while (sva < eva) {
4377 		next_bucket = L2_NEXT_BUCKET(sva);
4378 
4379 		/*
4380 		 * Check for large page.
4381 		 */
4382 		l1pd = pmap->pm_l1->l1_kva[L1_IDX(sva)];
4383 		if ((l1pd & L1_TYPE_MASK) == L1_S_PROTO) {
4384 			KASSERT((l1pd & L1_S_DOM_MASK) !=
4385 			    L1_S_DOM(PMAP_DOMAIN_KERNEL), ("pmap_remove: "
4386 			    "Trying to remove kernel section mapping"));
4387 			/*
4388 			 * Are we removing the entire large page?  If not,
4389 			 * demote the mapping and fall through.
4390 			 */
4391 			if (sva + L1_S_SIZE == next_bucket &&
4392 			    eva >= next_bucket) {
4393 				pmap_remove_section(pmap, sva);
4394 				sva = next_bucket;
4395 				continue;
4396 			} else if (!pmap_demote_section(pmap, sva)) {
4397 				/* The large page mapping was destroyed. */
4398 				sva = next_bucket;
4399 				continue;
4400 			}
4401 		}
4402 		/*
4403 		 * Do one L2 bucket's worth at a time.
4404 		 */
4405 		if (next_bucket > eva)
4406 			next_bucket = eva;
4407 
4408 		l2b = pmap_get_l2_bucket(pmap, sva);
4409 		if (l2b == NULL) {
4410 			sva = next_bucket;
4411 			continue;
4412 		}
4413 
4414 		ptep = &l2b->l2b_kva[l2pte_index(sva)];
4415 		mappings = 0;
4416 
4417 		while (sva < next_bucket) {
4418 			struct vm_page *m;
4419 			pt_entry_t pte;
4420 			vm_paddr_t pa;
4421 
4422 			pte = *ptep;
4423 
4424 			if (pte == 0) {
4425 				/*
4426 				 * Nothing here, move along
4427 				 */
4428 				sva += PAGE_SIZE;
4429 				ptep++;
4430 				continue;
4431 			}
4432 
4433 			pmap->pm_stats.resident_count--;
4434 			pa = l2pte_pa(pte);
4435 			is_exec = 0;
4436 			is_refd = 1;
4437 
4438 			/*
4439 			 * Update flags. In a number of circumstances,
4440 			 * we could cluster a lot of these and do a
4441 			 * number of sequential pages in one go.
4442 			 */
4443 			if ((m = PHYS_TO_VM_PAGE(pa)) != NULL) {
4444 				struct pv_entry *pve;
4445 
4446 				pve = pmap_remove_pv(m, pmap, sva);
4447 				if (pve) {
4448 					is_exec = PTE_BEEN_EXECD(pte);
4449 					is_refd = PTE_BEEN_REFD(pte);
4450 					pmap_free_pv_entry(pmap, pve);
4451 				}
4452 			}
4453 
4454 			*ptep = 0;
4455 			PTE_SYNC(ptep);
4456 			if (pmap_is_current(pmap)) {
4457 				total++;
4458 				if (total < PMAP_REMOVE_CLEAN_LIST_SIZE) {
4459 					if (is_exec)
4460 						cpu_tlb_flushID_SE(sva);
4461 					else if (is_refd)
4462 						cpu_tlb_flushD_SE(sva);
4463 				} else if (total == PMAP_REMOVE_CLEAN_LIST_SIZE)
4464 					flushall = 1;
4465 			}
4466 
4467 			sva += PAGE_SIZE;
4468 			ptep++;
4469 			mappings++;
4470 		}
4471 
4472 		pmap_free_l2_bucket(pmap, l2b, mappings);
4473 	}
4474 
4475 	rw_wunlock(&pvh_global_lock);
4476 	if (flushall)
4477 		cpu_tlb_flushID();
4478 	cpu_cpwait();
4479 
4480 	PMAP_UNLOCK(pmap);
4481 }
4482 
4483 /*
4484  * pmap_zero_page()
4485  *
4486  * Zero a given physical page by mapping it at a page hook point.
4487  * In doing the zero page op, the page we zero is mapped cachable, as with
4488  * StrongARM accesses to non-cached pages are non-burst making writing
4489  * _any_ bulk data very slow.
4490  */
4491 static void
4492 pmap_zero_page_gen(vm_page_t m, int off, int size)
4493 {
4494 	struct czpages *czp;
4495 
4496 	KASSERT(TAILQ_EMPTY(&m->md.pv_list),
4497 	    ("pmap_zero_page_gen: page has mappings"));
4498 
4499 	vm_paddr_t phys = VM_PAGE_TO_PHYS(m);
4500 
4501 	sched_pin();
4502 	czp = &cpu_czpages[PCPU_GET(cpuid)];
4503 	mtx_lock(&czp->lock);
4504 
4505 	/*
4506 	 * Hook in the page, zero it.
4507 	 */
4508 	*czp->dstptep = L2_S_PROTO | phys | pte_l2_s_cache_mode | L2_S_REF;
4509 	pmap_set_prot(czp->dstptep, VM_PROT_WRITE, 0);
4510 	PTE_SYNC(czp->dstptep);
4511 	cpu_tlb_flushD_SE(czp->dstva);
4512 	cpu_cpwait();
4513 
4514 	if (off || size != PAGE_SIZE)
4515 		bzero((void *)(czp->dstva + off), size);
4516 	else
4517 		bzero_page(czp->dstva);
4518 
4519 	/*
4520 	 * Although aliasing is not possible, if we use temporary mappings with
4521 	 * memory that will be mapped later as non-cached or with write-through
4522 	 * caches, we might end up overwriting it when calling wbinv_all.  So
4523 	 * make sure caches are clean after the operation.
4524 	 */
4525 	cpu_idcache_wbinv_range(czp->dstva, size);
4526 	pmap_l2cache_wbinv_range(czp->dstva, phys, size);
4527 
4528 	mtx_unlock(&czp->lock);
4529 	sched_unpin();
4530 }
4531 
4532 /*
4533  *	pmap_zero_page zeros the specified hardware page by mapping
4534  *	the page into KVM and using bzero to clear its contents.
4535  */
4536 void
4537 pmap_zero_page(vm_page_t m)
4538 {
4539 	pmap_zero_page_gen(m, 0, PAGE_SIZE);
4540 }
4541 
4542 
4543 /*
4544  *	pmap_zero_page_area zeros the specified hardware page by mapping
4545  *	the page into KVM and using bzero to clear its contents.
4546  *
4547  *	off and size may not cover an area beyond a single hardware page.
4548  */
4549 void
4550 pmap_zero_page_area(vm_page_t m, int off, int size)
4551 {
4552 
4553 	pmap_zero_page_gen(m, off, size);
4554 }
4555 
4556 
4557 /*
4558  *	pmap_zero_page_idle zeros the specified hardware page by mapping
4559  *	the page into KVM and using bzero to clear its contents.  This
4560  *	is intended to be called from the vm_pagezero process only and
4561  *	outside of Giant.
4562  */
4563 void
4564 pmap_zero_page_idle(vm_page_t m)
4565 {
4566 
4567 	pmap_zero_page(m);
4568 }
4569 
4570 /*
4571  *	pmap_copy_page copies the specified (machine independent)
4572  *	page by mapping the page into virtual memory and using
4573  *	bcopy to copy the page, one machine dependent page at a
4574  *	time.
4575  */
4576 
4577 /*
4578  * pmap_copy_page()
4579  *
4580  * Copy one physical page into another, by mapping the pages into
4581  * hook points. The same comment regarding cachability as in
4582  * pmap_zero_page also applies here.
4583  */
4584 void
4585 pmap_copy_page_generic(vm_paddr_t src, vm_paddr_t dst)
4586 {
4587 	struct czpages *czp;
4588 
4589 	sched_pin();
4590 	czp = &cpu_czpages[PCPU_GET(cpuid)];
4591 	mtx_lock(&czp->lock);
4592 
4593 	/*
4594 	 * Map the pages into the page hook points, copy them, and purge the
4595 	 * cache for the appropriate page.
4596 	 */
4597 	*czp->srcptep = L2_S_PROTO | src | pte_l2_s_cache_mode | L2_S_REF;
4598 	pmap_set_prot(czp->srcptep, VM_PROT_READ, 0);
4599 	PTE_SYNC(czp->srcptep);
4600 	cpu_tlb_flushD_SE(czp->srcva);
4601 	*czp->dstptep = L2_S_PROTO | dst | pte_l2_s_cache_mode | L2_S_REF;
4602 	pmap_set_prot(czp->dstptep, VM_PROT_READ | VM_PROT_WRITE, 0);
4603 	PTE_SYNC(czp->dstptep);
4604 	cpu_tlb_flushD_SE(czp->dstva);
4605 	cpu_cpwait();
4606 
4607 	bcopy_page(czp->srcva, czp->dstva);
4608 
4609 	/*
4610 	 * Although aliasing is not possible, if we use temporary mappings with
4611 	 * memory that will be mapped later as non-cached or with write-through
4612 	 * caches, we might end up overwriting it when calling wbinv_all.  So
4613 	 * make sure caches are clean after the operation.
4614 	 */
4615 	cpu_idcache_wbinv_range(czp->dstva, PAGE_SIZE);
4616 	pmap_l2cache_wbinv_range(czp->dstva, dst, PAGE_SIZE);
4617 
4618 	mtx_unlock(&czp->lock);
4619 	sched_unpin();
4620 }
4621 
4622 int unmapped_buf_allowed = 1;
4623 
4624 void
4625 pmap_copy_pages(vm_page_t ma[], vm_offset_t a_offset, vm_page_t mb[],
4626     vm_offset_t b_offset, int xfersize)
4627 {
4628 	vm_page_t a_pg, b_pg;
4629 	vm_offset_t a_pg_offset, b_pg_offset;
4630 	int cnt;
4631 	struct czpages *czp;
4632 
4633 	sched_pin();
4634 	czp = &cpu_czpages[PCPU_GET(cpuid)];
4635 	mtx_lock(&czp->lock);
4636 
4637 	while (xfersize > 0) {
4638 		a_pg = ma[a_offset >> PAGE_SHIFT];
4639 		a_pg_offset = a_offset & PAGE_MASK;
4640 		cnt = min(xfersize, PAGE_SIZE - a_pg_offset);
4641 		b_pg = mb[b_offset >> PAGE_SHIFT];
4642 		b_pg_offset = b_offset & PAGE_MASK;
4643 		cnt = min(cnt, PAGE_SIZE - b_pg_offset);
4644 		*czp->srcptep = L2_S_PROTO | VM_PAGE_TO_PHYS(a_pg) |
4645 		    pte_l2_s_cache_mode | L2_S_REF;
4646 		pmap_set_prot(czp->srcptep, VM_PROT_READ, 0);
4647 		PTE_SYNC(czp->srcptep);
4648 		cpu_tlb_flushD_SE(czp->srcva);
4649 		*czp->dstptep = L2_S_PROTO | VM_PAGE_TO_PHYS(b_pg) |
4650 		    pte_l2_s_cache_mode | L2_S_REF;
4651 		pmap_set_prot(czp->dstptep, VM_PROT_READ | VM_PROT_WRITE, 0);
4652 		PTE_SYNC(czp->dstptep);
4653 		cpu_tlb_flushD_SE(czp->dstva);
4654 		cpu_cpwait();
4655 		bcopy((char *)czp->srcva + a_pg_offset, (char *)czp->dstva + b_pg_offset,
4656 		    cnt);
4657 		cpu_idcache_wbinv_range(czp->dstva + b_pg_offset, cnt);
4658 		pmap_l2cache_wbinv_range(czp->dstva + b_pg_offset,
4659 		    VM_PAGE_TO_PHYS(b_pg) + b_pg_offset, cnt);
4660 		xfersize -= cnt;
4661 		a_offset += cnt;
4662 		b_offset += cnt;
4663 	}
4664 
4665 	mtx_unlock(&czp->lock);
4666 	sched_unpin();
4667 }
4668 
4669 void
4670 pmap_copy_page(vm_page_t src, vm_page_t dst)
4671 {
4672 
4673 	if (_arm_memcpy && PAGE_SIZE >= _min_memcpy_size &&
4674 	    _arm_memcpy((void *)VM_PAGE_TO_PHYS(dst),
4675 	    (void *)VM_PAGE_TO_PHYS(src), PAGE_SIZE, IS_PHYSICAL) == 0)
4676 		return;
4677 
4678 	pmap_copy_page_generic(VM_PAGE_TO_PHYS(src), VM_PAGE_TO_PHYS(dst));
4679 }
4680 
4681 /*
4682  * this routine returns true if a physical page resides
4683  * in the given pmap.
4684  */
4685 boolean_t
4686 pmap_page_exists_quick(pmap_t pmap, vm_page_t m)
4687 {
4688 	struct md_page *pvh;
4689 	pv_entry_t pv;
4690 	int loops = 0;
4691 	boolean_t rv;
4692 
4693 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
4694 	    ("pmap_page_exists_quick: page %p is not managed", m));
4695 	rv = FALSE;
4696 	rw_wlock(&pvh_global_lock);
4697 	TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
4698 		if (PV_PMAP(pv) == pmap) {
4699 			rv = TRUE;
4700 			break;
4701 		}
4702 		loops++;
4703 		if (loops >= 16)
4704 			break;
4705 	}
4706 	if (!rv && loops < 16 && (m->flags & PG_FICTITIOUS) == 0) {
4707 		pvh = pa_to_pvh(VM_PAGE_TO_PHYS(m));
4708 		TAILQ_FOREACH(pv, &pvh->pv_list, pv_list) {
4709 			if (PV_PMAP(pv) == pmap) {
4710 				rv = TRUE;
4711 				break;
4712 			}
4713 			loops++;
4714 			if (loops >= 16)
4715 				break;
4716 		}
4717 	}
4718 	rw_wunlock(&pvh_global_lock);
4719 	return (rv);
4720 }
4721 
4722 /*
4723  *	pmap_page_wired_mappings:
4724  *
4725  *	Return the number of managed mappings to the given physical page
4726  *	that are wired.
4727  */
4728 int
4729 pmap_page_wired_mappings(vm_page_t m)
4730 {
4731 	int count;
4732 
4733 	count = 0;
4734 	if ((m->oflags & VPO_UNMANAGED) != 0)
4735 		return (count);
4736 	rw_wlock(&pvh_global_lock);
4737 	count = pmap_pvh_wired_mappings(&m->md, count);
4738 	if ((m->flags & PG_FICTITIOUS) == 0) {
4739 	    count = pmap_pvh_wired_mappings(pa_to_pvh(VM_PAGE_TO_PHYS(m)),
4740 	        count);
4741 	}
4742 	rw_wunlock(&pvh_global_lock);
4743 	return (count);
4744 }
4745 
4746 /*
4747  *	pmap_pvh_wired_mappings:
4748  *
4749  *	Return the updated number "count" of managed mappings that are wired.
4750  */
4751 static int
4752 pmap_pvh_wired_mappings(struct md_page *pvh, int count)
4753 {
4754 	pv_entry_t pv;
4755 
4756 	rw_assert(&pvh_global_lock, RA_WLOCKED);
4757 	TAILQ_FOREACH(pv, &pvh->pv_list, pv_list) {
4758 		if ((pv->pv_flags & PVF_WIRED) != 0)
4759 			count++;
4760 	}
4761 	return (count);
4762 }
4763 
4764 /*
4765  * Returns TRUE if any of the given mappings were referenced and FALSE
4766  * otherwise.  Both page and section mappings are supported.
4767  */
4768 static boolean_t
4769 pmap_is_referenced_pvh(struct md_page *pvh)
4770 {
4771 	struct l2_bucket *l2b;
4772 	pv_entry_t pv;
4773 	pd_entry_t *pl1pd;
4774 	pt_entry_t *ptep;
4775 	pmap_t pmap;
4776 	boolean_t rv;
4777 
4778 	rw_assert(&pvh_global_lock, RA_WLOCKED);
4779 	rv = FALSE;
4780 	TAILQ_FOREACH(pv, &pvh->pv_list, pv_list) {
4781 		pmap = PV_PMAP(pv);
4782 		PMAP_LOCK(pmap);
4783 		pl1pd = &pmap->pm_l1->l1_kva[L1_IDX(pv->pv_va)];
4784 		if ((*pl1pd & L1_TYPE_MASK) == L1_S_PROTO)
4785 			rv = L1_S_REFERENCED(*pl1pd);
4786 		else {
4787 			l2b = pmap_get_l2_bucket(pmap, pv->pv_va);
4788 			ptep = &l2b->l2b_kva[l2pte_index(pv->pv_va)];
4789 			rv = L2_S_REFERENCED(*ptep);
4790 		}
4791 		PMAP_UNLOCK(pmap);
4792 		if (rv)
4793 			break;
4794 	}
4795 	return (rv);
4796 }
4797 
4798 /*
4799  *	pmap_is_referenced:
4800  *
4801  *	Return whether or not the specified physical page was referenced
4802  *	in any physical maps.
4803  */
4804 boolean_t
4805 pmap_is_referenced(vm_page_t m)
4806 {
4807 	boolean_t rv;
4808 
4809 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
4810 	    ("pmap_is_referenced: page %p is not managed", m));
4811 	rw_wlock(&pvh_global_lock);
4812 	rv = pmap_is_referenced_pvh(&m->md) ||
4813 	    ((m->flags & PG_FICTITIOUS) == 0 &&
4814 	    pmap_is_referenced_pvh(pa_to_pvh(VM_PAGE_TO_PHYS(m))));
4815 	rw_wunlock(&pvh_global_lock);
4816 	return (rv);
4817 }
4818 
4819 /*
4820  *	pmap_ts_referenced:
4821  *
4822  *	Return the count of reference bits for a page, clearing all of them.
4823  */
4824 int
4825 pmap_ts_referenced(vm_page_t m)
4826 {
4827 
4828 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
4829 	    ("pmap_ts_referenced: page %p is not managed", m));
4830 	return (pmap_clearbit(m, PVF_REF));
4831 }
4832 
4833 /*
4834  * Returns TRUE if any of the given mappings were used to modify
4835  * physical memory. Otherwise, returns FALSE. Both page and 1MB section
4836  * mappings are supported.
4837  */
4838 static boolean_t
4839 pmap_is_modified_pvh(struct md_page *pvh)
4840 {
4841 	pd_entry_t *pl1pd;
4842 	struct l2_bucket *l2b;
4843 	pv_entry_t pv;
4844 	pt_entry_t *ptep;
4845 	pmap_t pmap;
4846 	boolean_t rv;
4847 
4848 	rw_assert(&pvh_global_lock, RA_WLOCKED);
4849 	rv = FALSE;
4850 
4851 	TAILQ_FOREACH(pv, &pvh->pv_list, pv_list) {
4852 		pmap = PV_PMAP(pv);
4853 		PMAP_LOCK(pmap);
4854 		pl1pd = &pmap->pm_l1->l1_kva[L1_IDX(pv->pv_va)];
4855 		if ((*pl1pd & L1_TYPE_MASK) == L1_S_PROTO)
4856 			rv = L1_S_WRITABLE(*pl1pd);
4857 		else {
4858 			l2b = pmap_get_l2_bucket(pmap, pv->pv_va);
4859 			ptep = &l2b->l2b_kva[l2pte_index(pv->pv_va)];
4860 			rv = L2_S_WRITABLE(*ptep);
4861 		}
4862 		PMAP_UNLOCK(pmap);
4863 		if (rv)
4864 			break;
4865 	}
4866 
4867 	return (rv);
4868 }
4869 
4870 boolean_t
4871 pmap_is_modified(vm_page_t m)
4872 {
4873 	boolean_t rv;
4874 
4875 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
4876 	    ("pmap_is_modified: page %p is not managed", m));
4877 	/*
4878 	 * If the page is not exclusive busied, then PGA_WRITEABLE cannot be
4879 	 * concurrently set while the object is locked.  Thus, if PGA_WRITEABLE
4880 	 * is clear, no PTEs can have APX cleared.
4881 	 */
4882 	VM_OBJECT_ASSERT_WLOCKED(m->object);
4883 	if (!vm_page_xbusied(m) && (m->aflags & PGA_WRITEABLE) == 0)
4884 		return (FALSE);
4885 	rw_wlock(&pvh_global_lock);
4886 	rv = pmap_is_modified_pvh(&m->md) ||
4887 	    ((m->flags & PG_FICTITIOUS) == 0 &&
4888 	    pmap_is_modified_pvh(pa_to_pvh(VM_PAGE_TO_PHYS(m))));
4889 	rw_wunlock(&pvh_global_lock);
4890 	return (rv);
4891 }
4892 
4893 /*
4894  *	Apply the given advice to the specified range of addresses within the
4895  *	given pmap.  Depending on the advice, clear the referenced and/or
4896  *	modified flags in each mapping.
4897  */
4898 void
4899 pmap_advise(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, int advice)
4900 {
4901 	struct l2_bucket *l2b;
4902 	struct pv_entry *pve;
4903 	pd_entry_t l1pd;
4904 	pt_entry_t *ptep, opte, pte;
4905 	vm_offset_t next_bucket;
4906 	vm_page_t m;
4907 
4908 	if (advice != MADV_DONTNEED && advice != MADV_FREE)
4909 		return;
4910 	rw_wlock(&pvh_global_lock);
4911 	PMAP_LOCK(pmap);
4912 	for (; sva < eva; sva = next_bucket) {
4913 		next_bucket = L2_NEXT_BUCKET(sva);
4914 		if (next_bucket < sva)
4915 			next_bucket = eva;
4916 		l1pd = pmap->pm_l1->l1_kva[L1_IDX(sva)];
4917 		if ((l1pd & L1_TYPE_MASK) == L1_S_PROTO) {
4918 			if (pmap == pmap_kernel())
4919 				continue;
4920 			if (!pmap_demote_section(pmap, sva)) {
4921 				/*
4922 				 * The large page mapping was destroyed.
4923 				 */
4924 				continue;
4925 			}
4926 			/*
4927 			 * Unless the page mappings are wired, remove the
4928 			 * mapping to a single page so that a subsequent
4929 			 * access may repromote. Since the underlying
4930 			 * l2_bucket is fully populated, this removal
4931 			 * never frees an entire l2_bucket.
4932 			 */
4933 			l2b = pmap_get_l2_bucket(pmap, sva);
4934 			KASSERT(l2b != NULL,
4935 			    ("pmap_advise: no l2 bucket for "
4936 			     "va 0x%#x, pmap 0x%p", sva, pmap));
4937 			ptep = &l2b->l2b_kva[l2pte_index(sva)];
4938 			opte = *ptep;
4939 			m = PHYS_TO_VM_PAGE(l2pte_pa(*ptep));
4940 			KASSERT(m != NULL,
4941 			    ("pmap_advise: no vm_page for demoted superpage"));
4942 			pve = pmap_find_pv(&m->md, pmap, sva);
4943 			KASSERT(pve != NULL,
4944 			    ("pmap_advise: no PV entry for managed mapping"));
4945 			if ((pve->pv_flags & PVF_WIRED) == 0) {
4946 				pmap_free_l2_bucket(pmap, l2b, 1);
4947 				pve = pmap_remove_pv(m, pmap, sva);
4948 				pmap_free_pv_entry(pmap, pve);
4949 				*ptep = 0;
4950 				PTE_SYNC(ptep);
4951 				if (pmap_is_current(pmap)) {
4952 					if (PTE_BEEN_EXECD(opte))
4953 						cpu_tlb_flushID_SE(sva);
4954 					else if (PTE_BEEN_REFD(opte))
4955 						cpu_tlb_flushD_SE(sva);
4956 				}
4957 			}
4958 		}
4959 		if (next_bucket > eva)
4960 			next_bucket = eva;
4961 		l2b = pmap_get_l2_bucket(pmap, sva);
4962 		if (l2b == NULL)
4963 			continue;
4964 		for (ptep = &l2b->l2b_kva[l2pte_index(sva)];
4965 		    sva != next_bucket; ptep++, sva += PAGE_SIZE) {
4966 			opte = pte = *ptep;
4967 			if ((opte & L2_S_PROTO) == 0)
4968 				continue;
4969 			m = PHYS_TO_VM_PAGE(l2pte_pa(opte));
4970 			if (m == NULL || (m->oflags & VPO_UNMANAGED) != 0)
4971 				continue;
4972 			else if (L2_S_WRITABLE(opte)) {
4973 				if (advice == MADV_DONTNEED) {
4974 					/*
4975 					 * Don't need to mark the page
4976 					 * dirty as it was already marked as
4977 					 * such in pmap_fault_fixup() or
4978 					 * pmap_enter_locked().
4979 					 * Just clear the state.
4980 					 */
4981 				} else
4982 					pte |= L2_APX;
4983 
4984 				pte &= ~L2_S_REF;
4985 				*ptep = pte;
4986 				PTE_SYNC(ptep);
4987 			} else if (L2_S_REFERENCED(opte)) {
4988 				pte &= ~L2_S_REF;
4989 				*ptep = pte;
4990 				PTE_SYNC(ptep);
4991 			} else
4992 				continue;
4993 			if (pmap_is_current(pmap)) {
4994 				if (PTE_BEEN_EXECD(opte))
4995 					cpu_tlb_flushID_SE(sva);
4996 				else if (PTE_BEEN_REFD(opte))
4997 					cpu_tlb_flushD_SE(sva);
4998 			}
4999 		}
5000 	}
5001 	cpu_cpwait();
5002 	rw_wunlock(&pvh_global_lock);
5003 	PMAP_UNLOCK(pmap);
5004 }
5005 
5006 /*
5007  *	Clear the modify bits on the specified physical page.
5008  */
5009 void
5010 pmap_clear_modify(vm_page_t m)
5011 {
5012 
5013 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
5014 	    ("pmap_clear_modify: page %p is not managed", m));
5015 	VM_OBJECT_ASSERT_WLOCKED(m->object);
5016 	KASSERT(!vm_page_xbusied(m),
5017 	    ("pmap_clear_modify: page %p is exclusive busied", m));
5018 
5019 	/*
5020 	 * If the page is not PGA_WRITEABLE, then no mappings can be modified.
5021 	 * If the object containing the page is locked and the page is not
5022 	 * exclusive busied, then PGA_WRITEABLE cannot be concurrently set.
5023 	 */
5024 	if ((m->aflags & PGA_WRITEABLE) == 0)
5025 		return;
5026 	if (pmap_is_modified(m))
5027 		pmap_clearbit(m, PVF_MOD);
5028 }
5029 
5030 
5031 /*
5032  * Clear the write and modified bits in each of the given page's mappings.
5033  */
5034 void
5035 pmap_remove_write(vm_page_t m)
5036 {
5037 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
5038 	    ("pmap_remove_write: page %p is not managed", m));
5039 
5040 	/*
5041 	 * If the page is not exclusive busied, then PGA_WRITEABLE cannot be
5042 	 * set by another thread while the object is locked.  Thus,
5043 	 * if PGA_WRITEABLE is clear, no page table entries need updating.
5044 	 */
5045 	VM_OBJECT_ASSERT_WLOCKED(m->object);
5046 	if (vm_page_xbusied(m) || (m->aflags & PGA_WRITEABLE) != 0)
5047 		pmap_clearbit(m, PVF_WRITE);
5048 }
5049 
5050 
5051 /*
5052  * perform the pmap work for mincore
5053  */
5054 int
5055 pmap_mincore(pmap_t pmap, vm_offset_t addr, vm_paddr_t *locked_pa)
5056 {
5057 	struct l2_bucket *l2b;
5058 	pd_entry_t *pl1pd, l1pd;
5059 	pt_entry_t *ptep, pte;
5060 	vm_paddr_t pa;
5061 	vm_page_t m;
5062 	int val;
5063 	boolean_t managed;
5064 
5065 	PMAP_LOCK(pmap);
5066 retry:
5067 	pl1pd = &pmap->pm_l1->l1_kva[L1_IDX(addr)];
5068 	l1pd = *pl1pd;
5069 	if ((l1pd & L1_TYPE_MASK) == L1_S_PROTO) {
5070 		pa = (l1pd & L1_S_FRAME);
5071 		val = MINCORE_SUPER | MINCORE_INCORE;
5072 		if (L1_S_WRITABLE(l1pd))
5073 			val |= MINCORE_MODIFIED | MINCORE_MODIFIED_OTHER;
5074 		managed = FALSE;
5075 		m = PHYS_TO_VM_PAGE(pa);
5076 		if (m != NULL && (m->oflags & VPO_UNMANAGED) == 0)
5077 			managed = TRUE;
5078 		if (managed) {
5079 			if (L1_S_REFERENCED(l1pd))
5080 				val |= MINCORE_REFERENCED |
5081 				    MINCORE_REFERENCED_OTHER;
5082 		}
5083 	} else {
5084 		l2b = pmap_get_l2_bucket(pmap, addr);
5085 		if (l2b == NULL) {
5086 			val = 0;
5087 			goto out;
5088 		}
5089 		ptep = &l2b->l2b_kva[l2pte_index(addr)];
5090 		pte = *ptep;
5091 		if (!l2pte_valid(pte)) {
5092 			val = 0;
5093 			goto out;
5094 		}
5095 		val = MINCORE_INCORE;
5096 		if (L2_S_WRITABLE(pte))
5097 			val |= MINCORE_MODIFIED | MINCORE_MODIFIED_OTHER;
5098 		managed = FALSE;
5099 		pa = l2pte_pa(pte);
5100 		m = PHYS_TO_VM_PAGE(pa);
5101 		if (m != NULL && (m->oflags & VPO_UNMANAGED) == 0)
5102 			managed = TRUE;
5103 		if (managed) {
5104 			if (L2_S_REFERENCED(pte))
5105 				val |= MINCORE_REFERENCED |
5106 				    MINCORE_REFERENCED_OTHER;
5107 		}
5108 	}
5109 	if ((val & (MINCORE_MODIFIED_OTHER | MINCORE_REFERENCED_OTHER)) !=
5110 	    (MINCORE_MODIFIED_OTHER | MINCORE_REFERENCED_OTHER) && managed) {
5111 		/* Ensure that "PHYS_TO_VM_PAGE(pa)->object" doesn't change. */
5112 		if (vm_page_pa_tryrelock(pmap, pa, locked_pa))
5113 			goto retry;
5114 	} else
5115 out:
5116 		PA_UNLOCK_COND(*locked_pa);
5117 	PMAP_UNLOCK(pmap);
5118 	return (val);
5119 }
5120 
5121 void
5122 pmap_sync_icache(pmap_t pmap, vm_offset_t va, vm_size_t sz)
5123 {
5124 }
5125 
5126 /*
5127  *	Increase the starting virtual address of the given mapping if a
5128  *	different alignment might result in more superpage mappings.
5129  */
5130 void
5131 pmap_align_superpage(vm_object_t object, vm_ooffset_t offset,
5132     vm_offset_t *addr, vm_size_t size)
5133 {
5134 	vm_offset_t superpage_offset;
5135 
5136 	if (size < NBPDR)
5137 		return;
5138 	if (object != NULL && (object->flags & OBJ_COLORED) != 0)
5139 		offset += ptoa(object->pg_color);
5140 	superpage_offset = offset & PDRMASK;
5141 	if (size - ((NBPDR - superpage_offset) & PDRMASK) < NBPDR ||
5142 	    (*addr & PDRMASK) == superpage_offset)
5143 		return;
5144 	if ((*addr & PDRMASK) < superpage_offset)
5145 		*addr = (*addr & ~PDRMASK) + superpage_offset;
5146 	else
5147 		*addr = ((*addr + PDRMASK) & ~PDRMASK) + superpage_offset;
5148 }
5149 
5150 /*
5151  * pmap_map_section:
5152  *
5153  *	Create a single section mapping.
5154  */
5155 void
5156 pmap_map_section(pmap_t pmap, vm_offset_t va, vm_offset_t pa, vm_prot_t prot,
5157     boolean_t ref)
5158 {
5159 	pd_entry_t *pl1pd, l1pd;
5160 	pd_entry_t fl;
5161 
5162 	KASSERT(((va | pa) & L1_S_OFFSET) == 0,
5163 	    ("Not a valid section mapping"));
5164 
5165 	fl = pte_l1_s_cache_mode;
5166 
5167 	pl1pd = &pmap->pm_l1->l1_kva[L1_IDX(va)];
5168 	l1pd = L1_S_PROTO | pa | L1_S_PROT(PTE_USER, prot) | fl |
5169 	    L1_S_DOM(pmap->pm_domain);
5170 
5171 	/* Mark page referenced if this section is a result of a promotion. */
5172 	if (ref == TRUE)
5173 		l1pd |= L1_S_REF;
5174 #ifdef SMP
5175 	l1pd |= L1_SHARED;
5176 #endif
5177 	*pl1pd = l1pd;
5178 	PTE_SYNC(pl1pd);
5179 }
5180 
5181 /*
5182  * pmap_link_l2pt:
5183  *
5184  *	Link the L2 page table specified by l2pv.pv_pa into the L1
5185  *	page table at the slot for "va".
5186  */
5187 void
5188 pmap_link_l2pt(vm_offset_t l1pt, vm_offset_t va, struct pv_addr *l2pv)
5189 {
5190 	pd_entry_t *pde = (pd_entry_t *) l1pt, proto;
5191 	u_int slot = va >> L1_S_SHIFT;
5192 
5193 	proto = L1_S_DOM(PMAP_DOMAIN_KERNEL) | L1_C_PROTO;
5194 
5195 #ifdef VERBOSE_INIT_ARM
5196 	printf("pmap_link_l2pt: pa=0x%x va=0x%x\n", l2pv->pv_pa, l2pv->pv_va);
5197 #endif
5198 
5199 	pde[slot + 0] = proto | (l2pv->pv_pa + 0x000);
5200 	PTE_SYNC(&pde[slot]);
5201 
5202 	SLIST_INSERT_HEAD(&kernel_pt_list, l2pv, pv_list);
5203 
5204 }
5205 
5206 /*
5207  * pmap_map_entry
5208  *
5209  *	Create a single page mapping.
5210  */
5211 void
5212 pmap_map_entry(vm_offset_t l1pt, vm_offset_t va, vm_offset_t pa, int prot,
5213     int cache)
5214 {
5215 	pd_entry_t *pde = (pd_entry_t *) l1pt;
5216 	pt_entry_t fl;
5217 	pt_entry_t *ptep;
5218 
5219 	KASSERT(((va | pa) & PAGE_MASK) == 0, ("ouin"));
5220 
5221 	fl = l2s_mem_types[cache];
5222 
5223 	if ((pde[va >> L1_S_SHIFT] & L1_TYPE_MASK) != L1_TYPE_C)
5224 		panic("pmap_map_entry: no L2 table for VA 0x%08x", va);
5225 
5226 	ptep = (pt_entry_t *)kernel_pt_lookup(pde[L1_IDX(va)] & L1_C_ADDR_MASK);
5227 
5228 	if (ptep == NULL)
5229 		panic("pmap_map_entry: can't find L2 table for VA 0x%08x", va);
5230 
5231 	ptep[l2pte_index(va)] = L2_S_PROTO | pa | fl | L2_S_REF;
5232 	pmap_set_prot(&ptep[l2pte_index(va)], prot, 0);
5233 	PTE_SYNC(&ptep[l2pte_index(va)]);
5234 }
5235 
5236 /*
5237  * pmap_map_chunk:
5238  *
5239  *	Map a chunk of memory using the most efficient mappings
5240  *	possible (section. large page, small page) into the
5241  *	provided L1 and L2 tables at the specified virtual address.
5242  */
5243 vm_size_t
5244 pmap_map_chunk(vm_offset_t l1pt, vm_offset_t va, vm_offset_t pa,
5245     vm_size_t size, int prot, int type)
5246 {
5247 	pd_entry_t *pde = (pd_entry_t *) l1pt;
5248 	pt_entry_t *ptep, f1, f2s, f2l;
5249 	vm_size_t resid;
5250 	int i;
5251 
5252 	resid = (size + (PAGE_SIZE - 1)) & ~(PAGE_SIZE - 1);
5253 
5254 	if (l1pt == 0)
5255 		panic("pmap_map_chunk: no L1 table provided");
5256 
5257 #ifdef VERBOSE_INIT_ARM
5258 	printf("pmap_map_chunk: pa=0x%x va=0x%x size=0x%x resid=0x%x "
5259 	    "prot=0x%x type=%d\n", pa, va, size, resid, prot, type);
5260 #endif
5261 
5262 	f1 = l1_mem_types[type];
5263 	f2l = l2l_mem_types[type];
5264 	f2s = l2s_mem_types[type];
5265 
5266 	size = resid;
5267 
5268 	while (resid > 0) {
5269 		/* See if we can use a section mapping. */
5270 		if (L1_S_MAPPABLE_P(va, pa, resid)) {
5271 #ifdef VERBOSE_INIT_ARM
5272 			printf("S");
5273 #endif
5274 			pde[va >> L1_S_SHIFT] = L1_S_PROTO | pa |
5275 			    L1_S_PROT(PTE_KERNEL, prot | VM_PROT_EXECUTE) |
5276 			    f1 | L1_S_DOM(PMAP_DOMAIN_KERNEL) | L1_S_REF;
5277 			PTE_SYNC(&pde[va >> L1_S_SHIFT]);
5278 			va += L1_S_SIZE;
5279 			pa += L1_S_SIZE;
5280 			resid -= L1_S_SIZE;
5281 			continue;
5282 		}
5283 
5284 		/*
5285 		 * Ok, we're going to use an L2 table.  Make sure
5286 		 * one is actually in the corresponding L1 slot
5287 		 * for the current VA.
5288 		 */
5289 		if ((pde[va >> L1_S_SHIFT] & L1_TYPE_MASK) != L1_TYPE_C)
5290 			panic("pmap_map_chunk: no L2 table for VA 0x%08x", va);
5291 
5292 		ptep = (pt_entry_t *) kernel_pt_lookup(
5293 		    pde[L1_IDX(va)] & L1_C_ADDR_MASK);
5294 		if (ptep == NULL)
5295 			panic("pmap_map_chunk: can't find L2 table for VA"
5296 			    "0x%08x", va);
5297 		/* See if we can use a L2 large page mapping. */
5298 		if (L2_L_MAPPABLE_P(va, pa, resid)) {
5299 #ifdef VERBOSE_INIT_ARM
5300 			printf("L");
5301 #endif
5302 			for (i = 0; i < 16; i++) {
5303 				ptep[l2pte_index(va) + i] =
5304 				    L2_L_PROTO | pa |
5305 				    L2_L_PROT(PTE_KERNEL, prot) | f2l;
5306 				PTE_SYNC(&ptep[l2pte_index(va) + i]);
5307 			}
5308 			va += L2_L_SIZE;
5309 			pa += L2_L_SIZE;
5310 			resid -= L2_L_SIZE;
5311 			continue;
5312 		}
5313 
5314 		/* Use a small page mapping. */
5315 #ifdef VERBOSE_INIT_ARM
5316 		printf("P");
5317 #endif
5318 		ptep[l2pte_index(va)] = L2_S_PROTO | pa | f2s | L2_S_REF;
5319 		pmap_set_prot(&ptep[l2pte_index(va)], prot, 0);
5320 		PTE_SYNC(&ptep[l2pte_index(va)]);
5321 		va += PAGE_SIZE;
5322 		pa += PAGE_SIZE;
5323 		resid -= PAGE_SIZE;
5324 	}
5325 #ifdef VERBOSE_INIT_ARM
5326 	printf("\n");
5327 #endif
5328 	return (size);
5329 
5330 }
5331 
5332 int
5333 pmap_dmap_iscurrent(pmap_t pmap)
5334 {
5335 	return(pmap_is_current(pmap));
5336 }
5337 
5338 void
5339 pmap_page_set_memattr(vm_page_t m, vm_memattr_t ma)
5340 {
5341 	/*
5342 	 * Remember the memattr in a field that gets used to set the appropriate
5343 	 * bits in the PTEs as mappings are established.
5344 	 */
5345 	m->md.pv_memattr = ma;
5346 
5347 	/*
5348 	 * It appears that this function can only be called before any mappings
5349 	 * for the page are established on ARM.  If this ever changes, this code
5350 	 * will need to walk the pv_list and make each of the existing mappings
5351 	 * uncacheable, being careful to sync caches and PTEs (and maybe
5352 	 * invalidate TLB?) for any current mapping it modifies.
5353 	 */
5354 	if (TAILQ_FIRST(&m->md.pv_list) != NULL)
5355 		panic("Can't change memattr on page with existing mappings");
5356 }
5357