xref: /freebsd/sys/i386/i386/pmap.c (revision fd1aa5b3)
1 /*-
2  * SPDX-License-Identifier: BSD-4-Clause
3  *
4  * Copyright (c) 1991 Regents of the University of California.
5  * All rights reserved.
6  * Copyright (c) 1994 John S. Dyson
7  * All rights reserved.
8  * Copyright (c) 1994 David Greenman
9  * All rights reserved.
10  * Copyright (c) 2005-2010 Alan L. Cox <alc@cs.rice.edu>
11  * All rights reserved.
12  *
13  * This code is derived from software contributed to Berkeley by
14  * the Systems Programming Group of the University of Utah Computer
15  * Science Department and William Jolitz of UUNET Technologies Inc.
16  *
17  * Redistribution and use in source and binary forms, with or without
18  * modification, are permitted provided that the following conditions
19  * are met:
20  * 1. Redistributions of source code must retain the above copyright
21  *    notice, this list of conditions and the following disclaimer.
22  * 2. Redistributions in binary form must reproduce the above copyright
23  *    notice, this list of conditions and the following disclaimer in the
24  *    documentation and/or other materials provided with the distribution.
25  * 3. All advertising materials mentioning features or use of this software
26  *    must display the following acknowledgement:
27  *	This product includes software developed by the University of
28  *	California, Berkeley and its contributors.
29  * 4. Neither the name of the University nor the names of its contributors
30  *    may be used to endorse or promote products derived from this software
31  *    without specific prior written permission.
32  *
33  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
34  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
35  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
36  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
37  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
38  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
39  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
40  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
41  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
42  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
43  * SUCH DAMAGE.
44  */
45 /*-
46  * Copyright (c) 2003 Networks Associates Technology, Inc.
47  * All rights reserved.
48  * Copyright (c) 2018 The FreeBSD Foundation
49  * All rights reserved.
50  *
51  * This software was developed for the FreeBSD Project by Jake Burkholder,
52  * Safeport Network Services, and Network Associates Laboratories, the
53  * Security Research Division of Network Associates, Inc. under
54  * DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA
55  * CHATS research program.
56  *
57  * Portions of this software were developed by
58  * Konstantin Belousov <kib@FreeBSD.org> under sponsorship from
59  * the FreeBSD Foundation.
60  *
61  * Redistribution and use in source and binary forms, with or without
62  * modification, are permitted provided that the following conditions
63  * are met:
64  * 1. Redistributions of source code must retain the above copyright
65  *    notice, this list of conditions and the following disclaimer.
66  * 2. Redistributions in binary form must reproduce the above copyright
67  *    notice, this list of conditions and the following disclaimer in the
68  *    documentation and/or other materials provided with the distribution.
69  *
70  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
71  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
72  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
73  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
74  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
75  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
76  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
77  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
78  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
79  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
80  * SUCH DAMAGE.
81  */
82 
83 #include <sys/cdefs.h>
84 /*
85  *	Manages physical address maps.
86  *
87  *	Since the information managed by this module is
88  *	also stored by the logical address mapping module,
89  *	this module may throw away valid virtual-to-physical
90  *	mappings at almost any time.  However, invalidations
91  *	of virtual-to-physical mappings must be done as
92  *	requested.
93  *
94  *	In order to cope with hardware architectures which
95  *	make virtual-to-physical map invalidates expensive,
96  *	this module may delay invalidate or reduced protection
97  *	operations until such time as they are actually
98  *	necessary.  This module is given full information as
99  *	to which processors are currently using which maps,
100  *	and to when physical maps must be made correct.
101  */
102 
103 #include "opt_apic.h"
104 #include "opt_cpu.h"
105 #include "opt_pmap.h"
106 #include "opt_smp.h"
107 #include "opt_vm.h"
108 
109 #include <sys/param.h>
110 #include <sys/systm.h>
111 #include <sys/kernel.h>
112 #include <sys/ktr.h>
113 #include <sys/lock.h>
114 #include <sys/malloc.h>
115 #include <sys/mman.h>
116 #include <sys/msgbuf.h>
117 #include <sys/mutex.h>
118 #include <sys/proc.h>
119 #include <sys/rwlock.h>
120 #include <sys/sbuf.h>
121 #include <sys/sf_buf.h>
122 #include <sys/sx.h>
123 #include <sys/vmmeter.h>
124 #include <sys/sched.h>
125 #include <sys/sysctl.h>
126 #include <sys/smp.h>
127 #include <sys/vmem.h>
128 
129 #include <vm/vm.h>
130 #include <vm/vm_param.h>
131 #include <vm/vm_kern.h>
132 #include <vm/vm_page.h>
133 #include <vm/vm_map.h>
134 #include <vm/vm_object.h>
135 #include <vm/vm_extern.h>
136 #include <vm/vm_pageout.h>
137 #include <vm/vm_pager.h>
138 #include <vm/vm_phys.h>
139 #include <vm/vm_radix.h>
140 #include <vm/vm_reserv.h>
141 #include <vm/uma.h>
142 
143 #ifdef DEV_APIC
144 #include <sys/bus.h>
145 #include <machine/intr_machdep.h>
146 #include <x86/apicvar.h>
147 #endif
148 #include <x86/ifunc.h>
149 #include <machine/bootinfo.h>
150 #include <machine/cpu.h>
151 #include <machine/cputypes.h>
152 #include <machine/md_var.h>
153 #include <machine/pcb.h>
154 #include <machine/specialreg.h>
155 #ifdef SMP
156 #include <machine/smp.h>
157 #endif
158 #include <machine/pmap_base.h>
159 
160 #ifdef PV_STATS
161 #define PV_STAT(x)	do { x ; } while (0)
162 #else
163 #define PV_STAT(x)	do { } while (0)
164 #endif
165 
166 #define	pa_index(pa)	((pa) >> PDRSHIFT)
167 #define	pa_to_pvh(pa)	(&pv_table[pa_index(pa)])
168 
169 /*
170  * PTmap is recursive pagemap at top of virtual address space.
171  * Within PTmap, the page directory can be found (third indirection).
172  */
173 #define	PTmap	((pt_entry_t *)(PTDPTDI << PDRSHIFT))
174 #define	PTD	((pd_entry_t *)((PTDPTDI << PDRSHIFT) + (PTDPTDI * PAGE_SIZE)))
175 #define	PTDpde	((pd_entry_t *)((PTDPTDI << PDRSHIFT) + (PTDPTDI * PAGE_SIZE) + \
176     (PTDPTDI * PDESIZE)))
177 
178 /*
179  * Translate a virtual address to the kernel virtual address of its page table
180  * entry (PTE).  This can be used recursively.  If the address of a PTE as
181  * previously returned by this macro is itself given as the argument, then the
182  * address of the page directory entry (PDE) that maps the PTE will be
183  * returned.
184  *
185  * This macro may be used before pmap_bootstrap() is called.
186  */
187 #define	vtopte(va)	(PTmap + i386_btop(va))
188 
189 /*
190  * Get PDEs and PTEs for user/kernel address space
191  */
192 #define	pmap_pde(m, v)	(&((m)->pm_pdir[(vm_offset_t)(v) >> PDRSHIFT]))
193 #define pdir_pde(m, v) (m[(vm_offset_t)(v) >> PDRSHIFT])
194 
195 #define pmap_pde_v(pte)		((*(int *)pte & PG_V) != 0)
196 #define pmap_pte_w(pte)		((*(int *)pte & PG_W) != 0)
197 #define pmap_pte_m(pte)		((*(int *)pte & PG_M) != 0)
198 #define pmap_pte_u(pte)		((*(int *)pte & PG_A) != 0)
199 #define pmap_pte_v(pte)		((*(int *)pte & PG_V) != 0)
200 
201 #define pmap_pte_set_w(pte, v)	((v) ? atomic_set_int((u_int *)(pte), PG_W) : \
202     atomic_clear_int((u_int *)(pte), PG_W))
203 #define pmap_pte_set_prot(pte, v) ((*(int *)pte &= ~PG_PROT), (*(int *)pte |= (v)))
204 
205 static int pgeflag = 0;		/* PG_G or-in */
206 static int pseflag = 0;		/* PG_PS or-in */
207 
208 static int nkpt = NKPT;
209 
210 #ifdef PMAP_PAE_COMP
211 pt_entry_t pg_nx;
212 static uma_zone_t pdptzone;
213 #else
214 #define	pg_nx	0
215 #endif
216 
217 _Static_assert(VM_MAXUSER_ADDRESS == VADDR(TRPTDI, 0), "VM_MAXUSER_ADDRESS");
218 _Static_assert(VM_MAX_KERNEL_ADDRESS <= VADDR(PTDPTDI, 0),
219     "VM_MAX_KERNEL_ADDRESS");
220 _Static_assert(PMAP_MAP_LOW == VADDR(LOWPTDI, 0), "PMAP_MAP_LOW");
221 _Static_assert(KERNLOAD == (KERNPTDI << PDRSHIFT), "KERNLOAD");
222 
223 extern int pat_works;
224 extern int pg_ps_enabled;
225 
226 extern int elf32_nxstack;
227 
228 #define	PAT_INDEX_SIZE	8
229 static int pat_index[PAT_INDEX_SIZE];	/* cache mode to PAT index conversion */
230 
231 /*
232  * pmap_mapdev support pre initialization (i.e. console)
233  */
234 #define	PMAP_PREINIT_MAPPING_COUNT	8
235 static struct pmap_preinit_mapping {
236 	vm_paddr_t	pa;
237 	vm_offset_t	va;
238 	vm_size_t	sz;
239 	int		mode;
240 } pmap_preinit_mapping[PMAP_PREINIT_MAPPING_COUNT];
241 static int pmap_initialized;
242 
243 static struct rwlock_padalign pvh_global_lock;
244 
245 /*
246  * Data for the pv entry allocation mechanism
247  */
248 static TAILQ_HEAD(pch, pv_chunk) pv_chunks = TAILQ_HEAD_INITIALIZER(pv_chunks);
249 extern int pv_entry_max, pv_entry_count;
250 static int pv_entry_high_water = 0;
251 static struct md_page *pv_table;
252 extern int shpgperproc;
253 
254 static struct pv_chunk *pv_chunkbase;	/* KVA block for pv_chunks */
255 static int pv_maxchunks;		/* How many chunks we have KVA for */
256 static vm_offset_t pv_vafree;		/* freelist stored in the PTE */
257 
258 /*
259  * All those kernel PT submaps that BSD is so fond of
260  */
261 static pt_entry_t *CMAP3;
262 static pd_entry_t *KPTD;
263 static caddr_t CADDR3;
264 
265 /*
266  * Crashdump maps.
267  */
268 static caddr_t crashdumpmap;
269 
270 static pt_entry_t *PMAP1 = NULL, *PMAP2, *PMAP3;
271 static pt_entry_t *PADDR1 = NULL, *PADDR2, *PADDR3;
272 #ifdef SMP
273 static int PMAP1cpu, PMAP3cpu;
274 extern int PMAP1changedcpu;
275 #endif
276 extern int PMAP1changed;
277 extern int PMAP1unchanged;
278 static struct mtx PMAP2mutex;
279 
280 /*
281  * Internal flags for pmap_enter()'s helper functions.
282  */
283 #define	PMAP_ENTER_NORECLAIM	0x1000000	/* Don't reclaim PV entries. */
284 #define	PMAP_ENTER_NOREPLACE	0x2000000	/* Don't replace mappings. */
285 
286 static void	free_pv_chunk(struct pv_chunk *pc);
287 static void	free_pv_entry(pmap_t pmap, pv_entry_t pv);
288 static pv_entry_t get_pv_entry(pmap_t pmap, bool try);
289 static void	pmap_pv_demote_pde(pmap_t pmap, vm_offset_t va, vm_paddr_t pa);
290 static bool	pmap_pv_insert_pde(pmap_t pmap, vm_offset_t va, pd_entry_t pde,
291 		    u_int flags);
292 #if VM_NRESERVLEVEL > 0
293 static void	pmap_pv_promote_pde(pmap_t pmap, vm_offset_t va, vm_paddr_t pa);
294 #endif
295 static void	pmap_pvh_free(struct md_page *pvh, pmap_t pmap, vm_offset_t va);
296 static pv_entry_t pmap_pvh_remove(struct md_page *pvh, pmap_t pmap,
297 		    vm_offset_t va);
298 static int	pmap_pvh_wired_mappings(struct md_page *pvh, int count);
299 
300 static void	pmap_abort_ptp(pmap_t pmap, vm_offset_t va, vm_page_t mpte);
301 static bool	pmap_demote_pde(pmap_t pmap, pd_entry_t *pde, vm_offset_t va);
302 static int	pmap_enter_4mpage(pmap_t pmap, vm_offset_t va, vm_page_t m,
303 		    vm_prot_t prot);
304 static int	pmap_enter_pde(pmap_t pmap, vm_offset_t va, pd_entry_t newpde,
305 		    u_int flags, vm_page_t m);
306 static vm_page_t pmap_enter_quick_locked(pmap_t pmap, vm_offset_t va,
307     vm_page_t m, vm_prot_t prot, vm_page_t mpte);
308 static int pmap_insert_pt_page(pmap_t pmap, vm_page_t mpte, bool promoted,
309     bool allpte_PG_A_set);
310 static void pmap_invalidate_pde_page(pmap_t pmap, vm_offset_t va,
311 		    pd_entry_t pde);
312 static void pmap_fill_ptp(pt_entry_t *firstpte, pt_entry_t newpte);
313 static bool pmap_is_modified_pvh(struct md_page *pvh);
314 static bool pmap_is_referenced_pvh(struct md_page *pvh);
315 static void pmap_kenter_attr(vm_offset_t va, vm_paddr_t pa, int mode);
316 static void pmap_kenter_pde(vm_offset_t va, pd_entry_t newpde);
317 static void pmap_pde_attr(pd_entry_t *pde, int cache_bits);
318 #if VM_NRESERVLEVEL > 0
319 static bool pmap_promote_pde(pmap_t pmap, pd_entry_t *pde, vm_offset_t va,
320     vm_page_t mpte);
321 #endif
322 static bool pmap_protect_pde(pmap_t pmap, pd_entry_t *pde, vm_offset_t sva,
323     vm_prot_t prot);
324 static void pmap_pte_attr(pt_entry_t *pte, int cache_bits);
325 static void pmap_remove_pde(pmap_t pmap, pd_entry_t *pdq, vm_offset_t sva,
326     struct spglist *free);
327 static int pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq, vm_offset_t sva,
328     struct spglist *free);
329 static vm_page_t pmap_remove_pt_page(pmap_t pmap, vm_offset_t va);
330 static void pmap_remove_page(pmap_t pmap, vm_offset_t va, struct spglist *free);
331 static bool	pmap_remove_ptes(pmap_t pmap, vm_offset_t sva, vm_offset_t eva,
332 		    struct spglist *free);
333 static void pmap_remove_entry(pmap_t pmap, vm_page_t m, vm_offset_t va);
334 static void pmap_insert_entry(pmap_t pmap, vm_offset_t va, vm_page_t m);
335 static bool pmap_try_insert_pv_entry(pmap_t pmap, vm_offset_t va,
336     vm_page_t m);
337 static void pmap_update_pde(pmap_t pmap, vm_offset_t va, pd_entry_t *pde,
338     pd_entry_t newpde);
339 static void pmap_update_pde_invalidate(vm_offset_t va, pd_entry_t newpde);
340 
341 static vm_page_t pmap_allocpte(pmap_t pmap, vm_offset_t va, u_int flags);
342 
343 static vm_page_t _pmap_allocpte(pmap_t pmap, u_int ptepindex, u_int flags);
344 static void _pmap_unwire_ptp(pmap_t pmap, vm_page_t m, struct spglist *free);
345 static pt_entry_t *pmap_pte_quick(pmap_t pmap, vm_offset_t va);
346 static void pmap_pte_release(pt_entry_t *pte);
347 static int pmap_unuse_pt(pmap_t, vm_offset_t, struct spglist *);
348 #ifdef PMAP_PAE_COMP
349 static void *pmap_pdpt_allocf(uma_zone_t zone, vm_size_t bytes, int domain,
350     uint8_t *flags, int wait);
351 #endif
352 static void pmap_init_trm(void);
353 static void pmap_invalidate_all_int(pmap_t pmap);
354 
355 static __inline void pagezero(void *page);
356 
357 CTASSERT(1 << PDESHIFT == sizeof(pd_entry_t));
358 CTASSERT(1 << PTESHIFT == sizeof(pt_entry_t));
359 
360 extern char _end[];
361 extern u_long physfree;	/* phys addr of next free page */
362 extern u_long vm86phystk;/* PA of vm86/bios stack */
363 extern u_long vm86paddr;/* address of vm86 region */
364 extern int vm86pa;	/* phys addr of vm86 region */
365 extern u_long KERNend;	/* phys addr end of kernel (just after bss) */
366 #ifdef PMAP_PAE_COMP
367 pd_entry_t *IdlePTD_pae;	/* phys addr of kernel PTD */
368 pdpt_entry_t *IdlePDPT;	/* phys addr of kernel PDPT */
369 pt_entry_t *KPTmap_pae;	/* address of kernel page tables */
370 #define	IdlePTD	IdlePTD_pae
371 #define	KPTmap	KPTmap_pae
372 #else
373 pd_entry_t *IdlePTD_nopae;
374 pt_entry_t *KPTmap_nopae;
375 #define	IdlePTD	IdlePTD_nopae
376 #define	KPTmap	KPTmap_nopae
377 #endif
378 extern u_long KPTphys;	/* phys addr of kernel page tables */
379 extern u_long tramp_idleptd;
380 
381 static u_long
allocpages(u_int cnt,u_long * physfree)382 allocpages(u_int cnt, u_long *physfree)
383 {
384 	u_long res;
385 
386 	res = *physfree;
387 	*physfree += PAGE_SIZE * cnt;
388 	bzero((void *)res, PAGE_SIZE * cnt);
389 	return (res);
390 }
391 
392 static void
pmap_cold_map(u_long pa,u_long va,u_long cnt)393 pmap_cold_map(u_long pa, u_long va, u_long cnt)
394 {
395 	pt_entry_t *pt;
396 
397 	for (pt = (pt_entry_t *)KPTphys + atop(va); cnt > 0;
398 	    cnt--, pt++, va += PAGE_SIZE, pa += PAGE_SIZE)
399 		*pt = pa | PG_V | PG_RW | PG_A | PG_M;
400 }
401 
402 static void
pmap_cold_mapident(u_long pa,u_long cnt)403 pmap_cold_mapident(u_long pa, u_long cnt)
404 {
405 
406 	pmap_cold_map(pa, pa, cnt);
407 }
408 
409 _Static_assert(LOWPTDI * 2 * NBPDR == KERNBASE,
410     "Broken double-map of zero PTD");
411 
412 static void
__CONCAT(PMTYPE,remap_lower)413 __CONCAT(PMTYPE, remap_lower)(bool enable)
414 {
415 	int i;
416 
417 	for (i = 0; i < LOWPTDI; i++)
418 		IdlePTD[i] = enable ? IdlePTD[LOWPTDI + i] : 0;
419 	load_cr3(rcr3());		/* invalidate TLB */
420 }
421 
422 /*
423  * Called from locore.s before paging is enabled.  Sets up the first
424  * kernel page table.  Since kernel is mapped with PA == VA, this code
425  * does not require relocations.
426  */
427 void
__CONCAT(PMTYPE,cold)428 __CONCAT(PMTYPE, cold)(void)
429 {
430 	pt_entry_t *pt;
431 	u_long a;
432 	u_int cr3, ncr4;
433 
434 	physfree = (u_long)&_end;
435 	if (bootinfo.bi_esymtab != 0)
436 		physfree = bootinfo.bi_esymtab;
437 	if (bootinfo.bi_kernend != 0)
438 		physfree = bootinfo.bi_kernend;
439 	physfree = roundup2(physfree, NBPDR);
440 	KERNend = physfree;
441 
442 	/* Allocate Kernel Page Tables */
443 	KPTphys = allocpages(NKPT, &physfree);
444 	KPTmap = (pt_entry_t *)KPTphys;
445 
446 	/* Allocate Page Table Directory */
447 #ifdef PMAP_PAE_COMP
448 	/* XXX only need 32 bytes (easier for now) */
449 	IdlePDPT = (pdpt_entry_t *)allocpages(1, &physfree);
450 #endif
451 	IdlePTD = (pd_entry_t *)allocpages(NPGPTD, &physfree);
452 
453 	/*
454 	 * Allocate KSTACK.  Leave a guard page between IdlePTD and
455 	 * proc0kstack, to control stack overflow for thread0 and
456 	 * prevent corruption of the page table.  We leak the guard
457 	 * physical memory due to 1:1 mappings.
458 	 */
459 	allocpages(1, &physfree);
460 	proc0kstack = allocpages(TD0_KSTACK_PAGES, &physfree);
461 
462 	/* vm86/bios stack */
463 	vm86phystk = allocpages(1, &physfree);
464 
465 	/* pgtable + ext + IOPAGES */
466 	vm86paddr = vm86pa = allocpages(3, &physfree);
467 
468 	/* Install page tables into PTD.  Page table page 1 is wasted. */
469 	for (a = 0; a < NKPT; a++)
470 		IdlePTD[a] = (KPTphys + ptoa(a)) | PG_V | PG_RW | PG_A | PG_M;
471 
472 #ifdef PMAP_PAE_COMP
473 	/* PAE install PTD pointers into PDPT */
474 	for (a = 0; a < NPGPTD; a++)
475 		IdlePDPT[a] = ((u_int)IdlePTD + ptoa(a)) | PG_V;
476 #endif
477 
478 	/*
479 	 * Install recursive mapping for kernel page tables into
480 	 * itself.
481 	 */
482 	for (a = 0; a < NPGPTD; a++)
483 		IdlePTD[PTDPTDI + a] = ((u_int)IdlePTD + ptoa(a)) | PG_V |
484 		    PG_RW;
485 
486 	/*
487 	 * Initialize page table pages mapping physical address zero
488 	 * through the (physical) end of the kernel.  Many of these
489 	 * pages must be reserved, and we reserve them all and map
490 	 * them linearly for convenience.  We do this even if we've
491 	 * enabled PSE above; we'll just switch the corresponding
492 	 * kernel PDEs before we turn on paging.
493 	 *
494 	 * This and all other page table entries allow read and write
495 	 * access for various reasons.  Kernel mappings never have any
496 	 * access restrictions.
497 	 */
498 	pmap_cold_mapident(0, atop(NBPDR) * LOWPTDI);
499 	pmap_cold_map(0, NBPDR * LOWPTDI, atop(NBPDR) * LOWPTDI);
500 	pmap_cold_mapident(KERNBASE, atop(KERNend - KERNBASE));
501 
502 	/* Map page table directory */
503 #ifdef PMAP_PAE_COMP
504 	pmap_cold_mapident((u_long)IdlePDPT, 1);
505 #endif
506 	pmap_cold_mapident((u_long)IdlePTD, NPGPTD);
507 
508 	/* Map early KPTmap.  It is really pmap_cold_mapident. */
509 	pmap_cold_map(KPTphys, (u_long)KPTmap, NKPT);
510 
511 	/* Map proc0kstack */
512 	pmap_cold_mapident(proc0kstack, TD0_KSTACK_PAGES);
513 	/* ISA hole already mapped */
514 
515 	pmap_cold_mapident(vm86phystk, 1);
516 	pmap_cold_mapident(vm86pa, 3);
517 
518 	/* Map page 0 into the vm86 page table */
519 	*(pt_entry_t *)vm86pa = 0 | PG_RW | PG_U | PG_A | PG_M | PG_V;
520 
521 	/* ...likewise for the ISA hole for vm86 */
522 	for (pt = (pt_entry_t *)vm86pa + atop(ISA_HOLE_START), a = 0;
523 	    a < atop(ISA_HOLE_LENGTH); a++, pt++)
524 		*pt = (ISA_HOLE_START + ptoa(a)) | PG_RW | PG_U | PG_A |
525 		    PG_M | PG_V;
526 
527 	/* Enable PSE, PGE, VME, and PAE if configured. */
528 	ncr4 = 0;
529 	if ((cpu_feature & CPUID_PSE) != 0) {
530 		ncr4 |= CR4_PSE;
531 		pseflag = PG_PS;
532 		/*
533 		 * Superpage mapping of the kernel text.  Existing 4k
534 		 * page table pages are wasted.
535 		 */
536 		for (a = KERNBASE; a < KERNend; a += NBPDR)
537 			IdlePTD[a >> PDRSHIFT] = a | PG_PS | PG_A | PG_M |
538 			    PG_RW | PG_V;
539 	}
540 	if ((cpu_feature & CPUID_PGE) != 0) {
541 		ncr4 |= CR4_PGE;
542 		pgeflag = PG_G;
543 	}
544 	ncr4 |= (cpu_feature & CPUID_VME) != 0 ? CR4_VME : 0;
545 #ifdef PMAP_PAE_COMP
546 	ncr4 |= CR4_PAE;
547 #endif
548 	if (ncr4 != 0)
549 		load_cr4(rcr4() | ncr4);
550 
551 	/* Now enable paging */
552 #ifdef PMAP_PAE_COMP
553 	cr3 = (u_int)IdlePDPT;
554 	if ((cpu_feature & CPUID_PAT) == 0)
555 		wbinvd();
556 #else
557 	cr3 = (u_int)IdlePTD;
558 #endif
559 	tramp_idleptd = cr3;
560 	load_cr3(cr3);
561 	load_cr0(rcr0() | CR0_PG);
562 
563 	/*
564 	 * Now running relocated at KERNBASE where the system is
565 	 * linked to run.
566 	 */
567 
568 	/*
569 	 * Remove the lowest part of the double mapping of low memory
570 	 * to get some null pointer checks.
571 	 */
572 	__CONCAT(PMTYPE, remap_lower)(false);
573 
574 	kernel_vm_end = /* 0 + */ NKPT * NBPDR;
575 #ifdef PMAP_PAE_COMP
576 	i386_pmap_VM_NFREEORDER = VM_NFREEORDER_PAE;
577 	i386_pmap_VM_LEVEL_0_ORDER = VM_LEVEL_0_ORDER_PAE;
578 	i386_pmap_PDRSHIFT = PDRSHIFT_PAE;
579 #else
580 	i386_pmap_VM_NFREEORDER = VM_NFREEORDER_NOPAE;
581 	i386_pmap_VM_LEVEL_0_ORDER = VM_LEVEL_0_ORDER_NOPAE;
582 	i386_pmap_PDRSHIFT = PDRSHIFT_NOPAE;
583 #endif
584 }
585 
586 static void
__CONCAT(PMTYPE,set_nx)587 __CONCAT(PMTYPE, set_nx)(void)
588 {
589 
590 #ifdef PMAP_PAE_COMP
591 	if ((amd_feature & AMDID_NX) == 0)
592 		return;
593 	pg_nx = PG_NX;
594 	elf32_nxstack = 1;
595 	/* EFER.EFER_NXE is set in initializecpu(). */
596 #endif
597 }
598 
599 /*
600  *	Bootstrap the system enough to run with virtual memory.
601  *
602  *	On the i386 this is called after pmap_cold() created initial
603  *	kernel page table and enabled paging, and just syncs the pmap
604  *	module with what has already been done.
605  */
606 static void
__CONCAT(PMTYPE,bootstrap)607 __CONCAT(PMTYPE, bootstrap)(vm_paddr_t firstaddr)
608 {
609 	vm_offset_t va;
610 	pt_entry_t *pte, *unused __unused;
611 	struct pcpu *pc;
612 	u_long res;
613 	int i;
614 
615 	res = atop(firstaddr - (vm_paddr_t)KERNLOAD);
616 
617 	/*
618 	 * Add a physical memory segment (vm_phys_seg) corresponding to the
619 	 * preallocated kernel page table pages so that vm_page structures
620 	 * representing these pages will be created.  The vm_page structures
621 	 * are required for promotion of the corresponding kernel virtual
622 	 * addresses to superpage mappings.
623 	 */
624 	vm_phys_early_add_seg(KPTphys, KPTphys + ptoa(nkpt));
625 
626 	/*
627 	 * Initialize the first available kernel virtual address.
628 	 * However, using "firstaddr" may waste a few pages of the
629 	 * kernel virtual address space, because pmap_cold() may not
630 	 * have mapped every physical page that it allocated.
631 	 * Preferably, pmap_cold() would provide a first unused
632 	 * virtual address in addition to "firstaddr".
633 	 */
634 	virtual_avail = (vm_offset_t)firstaddr;
635 	virtual_end = VM_MAX_KERNEL_ADDRESS;
636 
637 	/*
638 	 * Initialize the kernel pmap (which is statically allocated).
639 	 * Count bootstrap data as being resident in case any of this data is
640 	 * later unmapped (using pmap_remove()) and freed.
641 	 */
642 	PMAP_LOCK_INIT(kernel_pmap);
643 	kernel_pmap->pm_pdir = IdlePTD;
644 #ifdef PMAP_PAE_COMP
645 	kernel_pmap->pm_pdpt = IdlePDPT;
646 #endif
647 	CPU_FILL(&kernel_pmap->pm_active);	/* don't allow deactivation */
648 	kernel_pmap->pm_stats.resident_count = res;
649 	TAILQ_INIT(&kernel_pmap->pm_pvchunk);
650 	vm_radix_init(&kernel_pmap->pm_root);
651 
652  	/*
653 	 * Initialize the global pv list lock.
654 	 */
655 	rw_init(&pvh_global_lock, "pmap pv global");
656 
657 	/*
658 	 * Reserve some special page table entries/VA space for temporary
659 	 * mapping of pages.
660 	 */
661 #define	SYSMAP(c, p, v, n)	\
662 	v = (c)va; va += ((n)*PAGE_SIZE); p = pte; pte += (n);
663 
664 	va = virtual_avail;
665 	pte = vtopte(va);
666 
667 	/*
668 	 * Initialize temporary map objects on the current CPU for use
669 	 * during early boot.
670 	 * CMAP1/CMAP2 are used for zeroing and copying pages.
671 	 * CMAP3 is used for the boot-time memory test.
672 	 */
673 	pc = get_pcpu();
674 	mtx_init(&pc->pc_cmap_lock, "SYSMAPS", NULL, MTX_DEF);
675 	SYSMAP(caddr_t, pc->pc_cmap_pte1, pc->pc_cmap_addr1, 1)
676 	SYSMAP(caddr_t, pc->pc_cmap_pte2, pc->pc_cmap_addr2, 1)
677 	SYSMAP(vm_offset_t, pte, pc->pc_qmap_addr, 1)
678 
679 	SYSMAP(caddr_t, CMAP3, CADDR3, 1);
680 
681 	/*
682 	 * Crashdump maps.
683 	 */
684 	SYSMAP(caddr_t, unused, crashdumpmap, MAXDUMPPGS)
685 
686 	/*
687 	 * ptvmmap is used for reading arbitrary physical pages via /dev/mem.
688 	 */
689 	SYSMAP(caddr_t, unused, ptvmmap, 1)
690 
691 	/*
692 	 * msgbufp is used to map the system message buffer.
693 	 */
694 	SYSMAP(struct msgbuf *, unused, msgbufp, atop(round_page(msgbufsize)))
695 
696 	/*
697 	 * KPTmap is used by pmap_kextract().
698 	 *
699 	 * KPTmap is first initialized by pmap_cold().  However, that initial
700 	 * KPTmap can only support NKPT page table pages.  Here, a larger
701 	 * KPTmap is created that can support KVA_PAGES page table pages.
702 	 */
703 	SYSMAP(pt_entry_t *, KPTD, KPTmap, KVA_PAGES)
704 
705 	for (i = 0; i < NKPT; i++)
706 		KPTD[i] = (KPTphys + ptoa(i)) | PG_RW | PG_V;
707 
708 	/*
709 	 * PADDR1 and PADDR2 are used by pmap_pte_quick() and pmap_pte(),
710 	 * respectively.
711 	 */
712 	SYSMAP(pt_entry_t *, PMAP1, PADDR1, 1)
713 	SYSMAP(pt_entry_t *, PMAP2, PADDR2, 1)
714 	SYSMAP(pt_entry_t *, PMAP3, PADDR3, 1)
715 
716 	mtx_init(&PMAP2mutex, "PMAP2", NULL, MTX_DEF);
717 
718 	virtual_avail = va;
719 
720 	/*
721 	 * Initialize the PAT MSR if present.
722 	 * pmap_init_pat() clears and sets CR4_PGE, which, as a
723 	 * side-effect, invalidates stale PG_G TLB entries that might
724 	 * have been created in our pre-boot environment.  We assume
725 	 * that PAT support implies PGE and in reverse, PGE presence
726 	 * comes with PAT.  Both features were added for Pentium Pro.
727 	 */
728 	pmap_init_pat();
729 }
730 
731 static void
pmap_init_reserved_pages(void)732 pmap_init_reserved_pages(void)
733 {
734 	struct pcpu *pc;
735 	vm_offset_t pages;
736 	int i;
737 
738 #ifdef PMAP_PAE_COMP
739 	if (!pae_mode)
740 		return;
741 #else
742 	if (pae_mode)
743 		return;
744 #endif
745 	CPU_FOREACH(i) {
746 		pc = pcpu_find(i);
747 		mtx_init(&pc->pc_copyout_mlock, "cpmlk", NULL, MTX_DEF |
748 		    MTX_NEW);
749 		pc->pc_copyout_maddr = kva_alloc(ptoa(2));
750 		if (pc->pc_copyout_maddr == 0)
751 			panic("unable to allocate non-sleepable copyout KVA");
752 		sx_init(&pc->pc_copyout_slock, "cpslk");
753 		pc->pc_copyout_saddr = kva_alloc(ptoa(2));
754 		if (pc->pc_copyout_saddr == 0)
755 			panic("unable to allocate sleepable copyout KVA");
756 		pc->pc_pmap_eh_va = kva_alloc(ptoa(1));
757 		if (pc->pc_pmap_eh_va == 0)
758 			panic("unable to allocate pmap_extract_and_hold KVA");
759 		pc->pc_pmap_eh_ptep = (char *)vtopte(pc->pc_pmap_eh_va);
760 
761 		/*
762 		 * Skip if the mappings have already been initialized,
763 		 * i.e. this is the BSP.
764 		 */
765 		if (pc->pc_cmap_addr1 != 0)
766 			continue;
767 
768 		mtx_init(&pc->pc_cmap_lock, "SYSMAPS", NULL, MTX_DEF);
769 		pages = kva_alloc(PAGE_SIZE * 3);
770 		if (pages == 0)
771 			panic("unable to allocate CMAP KVA");
772 		pc->pc_cmap_pte1 = vtopte(pages);
773 		pc->pc_cmap_pte2 = vtopte(pages + PAGE_SIZE);
774 		pc->pc_cmap_addr1 = (caddr_t)pages;
775 		pc->pc_cmap_addr2 = (caddr_t)(pages + PAGE_SIZE);
776 		pc->pc_qmap_addr = pages + ptoa(2);
777 	}
778 }
779 
780 SYSINIT(rpages_init, SI_SUB_CPU, SI_ORDER_ANY, pmap_init_reserved_pages, NULL);
781 
782 /*
783  * Setup the PAT MSR.
784  */
785 static void
__CONCAT(PMTYPE,init_pat)786 __CONCAT(PMTYPE, init_pat)(void)
787 {
788 	int pat_table[PAT_INDEX_SIZE];
789 	uint64_t pat_msr;
790 	u_long cr0, cr4;
791 	int i;
792 
793 	/* Set default PAT index table. */
794 	for (i = 0; i < PAT_INDEX_SIZE; i++)
795 		pat_table[i] = -1;
796 	pat_table[PAT_WRITE_BACK] = 0;
797 	pat_table[PAT_WRITE_THROUGH] = 1;
798 	pat_table[PAT_UNCACHEABLE] = 3;
799 	pat_table[PAT_WRITE_COMBINING] = 3;
800 	pat_table[PAT_WRITE_PROTECTED] = 3;
801 	pat_table[PAT_UNCACHED] = 3;
802 
803 	/*
804 	 * Bail if this CPU doesn't implement PAT.
805 	 * We assume that PAT support implies PGE.
806 	 */
807 	if ((cpu_feature & CPUID_PAT) == 0) {
808 		for (i = 0; i < PAT_INDEX_SIZE; i++)
809 			pat_index[i] = pat_table[i];
810 		pat_works = 0;
811 		return;
812 	}
813 
814 	/*
815 	 * Due to some Intel errata, we can only safely use the lower 4
816 	 * PAT entries.
817 	 *
818 	 *   Intel Pentium III Processor Specification Update
819 	 * Errata E.27 (Upper Four PAT Entries Not Usable With Mode B
820 	 * or Mode C Paging)
821 	 *
822 	 *   Intel Pentium IV  Processor Specification Update
823 	 * Errata N46 (PAT Index MSB May Be Calculated Incorrectly)
824 	 */
825 	if (cpu_vendor_id == CPU_VENDOR_INTEL &&
826 	    !(CPUID_TO_FAMILY(cpu_id) == 6 && CPUID_TO_MODEL(cpu_id) >= 0xe))
827 		pat_works = 0;
828 
829 	/* Initialize default PAT entries. */
830 	pat_msr = PAT_VALUE(0, PAT_WRITE_BACK) |
831 	    PAT_VALUE(1, PAT_WRITE_THROUGH) |
832 	    PAT_VALUE(2, PAT_UNCACHED) |
833 	    PAT_VALUE(3, PAT_UNCACHEABLE) |
834 	    PAT_VALUE(4, PAT_WRITE_BACK) |
835 	    PAT_VALUE(5, PAT_WRITE_THROUGH) |
836 	    PAT_VALUE(6, PAT_UNCACHED) |
837 	    PAT_VALUE(7, PAT_UNCACHEABLE);
838 
839 	if (pat_works) {
840 		/*
841 		 * Leave the indices 0-3 at the default of WB, WT, UC-, and UC.
842 		 * Program 5 and 6 as WP and WC.
843 		 * Leave 4 and 7 as WB and UC.
844 		 */
845 		pat_msr &= ~(PAT_MASK(5) | PAT_MASK(6));
846 		pat_msr |= PAT_VALUE(5, PAT_WRITE_PROTECTED) |
847 		    PAT_VALUE(6, PAT_WRITE_COMBINING);
848 		pat_table[PAT_UNCACHED] = 2;
849 		pat_table[PAT_WRITE_PROTECTED] = 5;
850 		pat_table[PAT_WRITE_COMBINING] = 6;
851 	} else {
852 		/*
853 		 * Just replace PAT Index 2 with WC instead of UC-.
854 		 */
855 		pat_msr &= ~PAT_MASK(2);
856 		pat_msr |= PAT_VALUE(2, PAT_WRITE_COMBINING);
857 		pat_table[PAT_WRITE_COMBINING] = 2;
858 	}
859 
860 	/* Disable PGE. */
861 	cr4 = rcr4();
862 	load_cr4(cr4 & ~CR4_PGE);
863 
864 	/* Disable caches (CD = 1, NW = 0). */
865 	cr0 = rcr0();
866 	load_cr0((cr0 & ~CR0_NW) | CR0_CD);
867 
868 	/* Flushes caches and TLBs. */
869 	wbinvd();
870 	invltlb();
871 
872 	/* Update PAT and index table. */
873 	wrmsr(MSR_PAT, pat_msr);
874 	for (i = 0; i < PAT_INDEX_SIZE; i++)
875 		pat_index[i] = pat_table[i];
876 
877 	/* Flush caches and TLBs again. */
878 	wbinvd();
879 	invltlb();
880 
881 	/* Restore caches and PGE. */
882 	load_cr0(cr0);
883 	load_cr4(cr4);
884 }
885 
886 #ifdef PMAP_PAE_COMP
887 static void *
pmap_pdpt_allocf(uma_zone_t zone,vm_size_t bytes,int domain,uint8_t * flags,int wait)888 pmap_pdpt_allocf(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *flags,
889     int wait)
890 {
891 
892 	/* Inform UMA that this allocator uses kernel_map/object. */
893 	*flags = UMA_SLAB_KERNEL;
894 	return ((void *)kmem_alloc_contig_domainset(DOMAINSET_FIXED(domain),
895 	    bytes, wait, 0x0ULL, 0xffffffffULL, 1, 0, VM_MEMATTR_DEFAULT));
896 }
897 #endif
898 
899 /*
900  * Abuse the pte nodes for unmapped kva to thread a kva freelist through.
901  * Requirements:
902  *  - Must deal with pages in order to ensure that none of the PG_* bits
903  *    are ever set, PG_V in particular.
904  *  - Assumes we can write to ptes without pte_store() atomic ops, even
905  *    on PAE systems.  This should be ok.
906  *  - Assumes nothing will ever test these addresses for 0 to indicate
907  *    no mapping instead of correctly checking PG_V.
908  *  - Assumes a vm_offset_t will fit in a pte (true for i386).
909  * Because PG_V is never set, there can be no mappings to invalidate.
910  */
911 static vm_offset_t
pmap_ptelist_alloc(vm_offset_t * head)912 pmap_ptelist_alloc(vm_offset_t *head)
913 {
914 	pt_entry_t *pte;
915 	vm_offset_t va;
916 
917 	va = *head;
918 	if (va == 0)
919 		panic("pmap_ptelist_alloc: exhausted ptelist KVA");
920 	pte = vtopte(va);
921 	*head = *pte;
922 	if (*head & PG_V)
923 		panic("pmap_ptelist_alloc: va with PG_V set!");
924 	*pte = 0;
925 	return (va);
926 }
927 
928 static void
pmap_ptelist_free(vm_offset_t * head,vm_offset_t va)929 pmap_ptelist_free(vm_offset_t *head, vm_offset_t va)
930 {
931 	pt_entry_t *pte;
932 
933 	if (va & PG_V)
934 		panic("pmap_ptelist_free: freeing va with PG_V set!");
935 	pte = vtopte(va);
936 	*pte = *head;		/* virtual! PG_V is 0 though */
937 	*head = va;
938 }
939 
940 static void
pmap_ptelist_init(vm_offset_t * head,void * base,int npages)941 pmap_ptelist_init(vm_offset_t *head, void *base, int npages)
942 {
943 	int i;
944 	vm_offset_t va;
945 
946 	*head = 0;
947 	for (i = npages - 1; i >= 0; i--) {
948 		va = (vm_offset_t)base + i * PAGE_SIZE;
949 		pmap_ptelist_free(head, va);
950 	}
951 }
952 
953 /*
954  *	Initialize the pmap module.
955  *	Called by vm_init, to initialize any structures that the pmap
956  *	system needs to map virtual memory.
957  */
958 static void
__CONCAT(PMTYPE,init)959 __CONCAT(PMTYPE, init)(void)
960 {
961 	struct pmap_preinit_mapping *ppim;
962 	vm_page_t mpte;
963 	vm_size_t s;
964 	int i, pv_npg;
965 
966 	/*
967 	 * Initialize the vm page array entries for the kernel pmap's
968 	 * page table pages.
969 	 */
970 	PMAP_LOCK(kernel_pmap);
971 	for (i = 0; i < NKPT; i++) {
972 		mpte = PHYS_TO_VM_PAGE(KPTphys + ptoa(i));
973 		KASSERT(mpte >= vm_page_array &&
974 		    mpte < &vm_page_array[vm_page_array_size],
975 		    ("pmap_init: page table page is out of range"));
976 		mpte->pindex = i + KPTDI;
977 		mpte->phys_addr = KPTphys + ptoa(i);
978 		mpte->ref_count = 1;
979 
980 		/*
981 		 * Collect the page table pages that were replaced by a 2/4MB
982 		 * page.  They are filled with equivalent 4KB page mappings.
983 		 */
984 		if (pseflag != 0 &&
985 		    KERNBASE <= i << PDRSHIFT && i << PDRSHIFT < KERNend &&
986 		    pmap_insert_pt_page(kernel_pmap, mpte, true, true))
987 			panic("pmap_init: pmap_insert_pt_page failed");
988 	}
989 	PMAP_UNLOCK(kernel_pmap);
990 	vm_wire_add(NKPT);
991 
992 	/*
993 	 * Initialize the address space (zone) for the pv entries.  Set a
994 	 * high water mark so that the system can recover from excessive
995 	 * numbers of pv entries.
996 	 */
997 	TUNABLE_INT_FETCH("vm.pmap.shpgperproc", &shpgperproc);
998 	pv_entry_max = shpgperproc * maxproc + vm_cnt.v_page_count;
999 	TUNABLE_INT_FETCH("vm.pmap.pv_entry_max", &pv_entry_max);
1000 	pv_entry_max = roundup(pv_entry_max, _NPCPV);
1001 	pv_entry_high_water = 9 * (pv_entry_max / 10);
1002 
1003 	/*
1004 	 * If the kernel is running on a virtual machine, then it must assume
1005 	 * that MCA is enabled by the hypervisor.  Moreover, the kernel must
1006 	 * be prepared for the hypervisor changing the vendor and family that
1007 	 * are reported by CPUID.  Consequently, the workaround for AMD Family
1008 	 * 10h Erratum 383 is enabled if the processor's feature set does not
1009 	 * include at least one feature that is only supported by older Intel
1010 	 * or newer AMD processors.
1011 	 */
1012 	if (vm_guest != VM_GUEST_NO && (cpu_feature & CPUID_SS) == 0 &&
1013 	    (cpu_feature2 & (CPUID2_SSSE3 | CPUID2_SSE41 | CPUID2_AESNI |
1014 	    CPUID2_AVX | CPUID2_XSAVE)) == 0 && (amd_feature2 & (AMDID2_XOP |
1015 	    AMDID2_FMA4)) == 0)
1016 		workaround_erratum383 = 1;
1017 
1018 	/*
1019 	 * Are large page mappings supported and enabled?
1020 	 */
1021 	TUNABLE_INT_FETCH("vm.pmap.pg_ps_enabled", &pg_ps_enabled);
1022 	if (pseflag == 0)
1023 		pg_ps_enabled = 0;
1024 	else if (pg_ps_enabled) {
1025 		KASSERT(MAXPAGESIZES > 1 && pagesizes[1] == 0,
1026 		    ("pmap_init: can't assign to pagesizes[1]"));
1027 		pagesizes[1] = NBPDR;
1028 	}
1029 
1030 	/*
1031 	 * Calculate the size of the pv head table for superpages.
1032 	 * Handle the possibility that "vm_phys_segs[...].end" is zero.
1033 	 */
1034 	pv_npg = trunc_4mpage(vm_phys_segs[vm_phys_nsegs - 1].end -
1035 	    PAGE_SIZE) / NBPDR + 1;
1036 
1037 	/*
1038 	 * Allocate memory for the pv head table for superpages.
1039 	 */
1040 	s = (vm_size_t)(pv_npg * sizeof(struct md_page));
1041 	s = round_page(s);
1042 	pv_table = kmem_malloc(s, M_WAITOK | M_ZERO);
1043 	for (i = 0; i < pv_npg; i++)
1044 		TAILQ_INIT(&pv_table[i].pv_list);
1045 
1046 	pv_maxchunks = MAX(pv_entry_max / _NPCPV, maxproc);
1047 	pv_chunkbase = (struct pv_chunk *)kva_alloc(PAGE_SIZE * pv_maxchunks);
1048 	if (pv_chunkbase == NULL)
1049 		panic("pmap_init: not enough kvm for pv chunks");
1050 	pmap_ptelist_init(&pv_vafree, pv_chunkbase, pv_maxchunks);
1051 #ifdef PMAP_PAE_COMP
1052 	pdptzone = uma_zcreate("PDPT", NPGPTD * sizeof(pdpt_entry_t), NULL,
1053 	    NULL, NULL, NULL, (NPGPTD * sizeof(pdpt_entry_t)) - 1,
1054 	    UMA_ZONE_CONTIG | UMA_ZONE_VM | UMA_ZONE_NOFREE);
1055 	uma_zone_set_allocf(pdptzone, pmap_pdpt_allocf);
1056 #endif
1057 
1058 	pmap_initialized = 1;
1059 	pmap_init_trm();
1060 
1061 	if (!bootverbose)
1062 		return;
1063 	for (i = 0; i < PMAP_PREINIT_MAPPING_COUNT; i++) {
1064 		ppim = pmap_preinit_mapping + i;
1065 		if (ppim->va == 0)
1066 			continue;
1067 		printf("PPIM %u: PA=%#jx, VA=%#x, size=%#x, mode=%#x\n", i,
1068 		    (uintmax_t)ppim->pa, ppim->va, ppim->sz, ppim->mode);
1069 	}
1070 
1071 }
1072 
1073 extern u_long pmap_pde_demotions;
1074 extern u_long pmap_pde_mappings;
1075 extern u_long pmap_pde_p_failures;
1076 extern u_long pmap_pde_promotions;
1077 
1078 /***************************************************
1079  * Low level helper routines.....
1080  ***************************************************/
1081 
1082 static bool
__CONCAT(PMTYPE,is_valid_memattr)1083 __CONCAT(PMTYPE, is_valid_memattr)(pmap_t pmap __unused, vm_memattr_t mode)
1084 {
1085 
1086 	return (mode >= 0 && mode < PAT_INDEX_SIZE &&
1087 	    pat_index[(int)mode] >= 0);
1088 }
1089 
1090 /*
1091  * Determine the appropriate bits to set in a PTE or PDE for a specified
1092  * caching mode.
1093  */
1094 static int
__CONCAT(PMTYPE,cache_bits)1095 __CONCAT(PMTYPE, cache_bits)(pmap_t pmap, int mode, bool is_pde)
1096 {
1097 	int cache_bits, pat_flag, pat_idx;
1098 
1099 	if (!pmap_is_valid_memattr(pmap, mode))
1100 		panic("Unknown caching mode %d\n", mode);
1101 
1102 	/* The PAT bit is different for PTE's and PDE's. */
1103 	pat_flag = is_pde ? PG_PDE_PAT : PG_PTE_PAT;
1104 
1105 	/* Map the caching mode to a PAT index. */
1106 	pat_idx = pat_index[mode];
1107 
1108 	/* Map the 3-bit index value into the PAT, PCD, and PWT bits. */
1109 	cache_bits = 0;
1110 	if (pat_idx & 0x4)
1111 		cache_bits |= pat_flag;
1112 	if (pat_idx & 0x2)
1113 		cache_bits |= PG_NC_PCD;
1114 	if (pat_idx & 0x1)
1115 		cache_bits |= PG_NC_PWT;
1116 	return (cache_bits);
1117 }
1118 
1119 static int
pmap_pat_index(pmap_t pmap,pt_entry_t pte,bool is_pde)1120 pmap_pat_index(pmap_t pmap, pt_entry_t pte, bool is_pde)
1121 {
1122 	int pat_flag, pat_idx;
1123 
1124 	if ((cpu_feature & CPUID_PAT) == 0)
1125 		return (0);
1126 
1127 	pat_idx = 0;
1128 	/* The PAT bit is different for PTE's and PDE's. */
1129 	pat_flag = is_pde ? PG_PDE_PAT : PG_PTE_PAT;
1130 
1131 	if ((pte & pat_flag) != 0)
1132 		pat_idx |= 0x4;
1133 	if ((pte & PG_NC_PCD) != 0)
1134 		pat_idx |= 0x2;
1135 	if ((pte & PG_NC_PWT) != 0)
1136 		pat_idx |= 0x1;
1137 
1138 	/* See pmap_init_pat(). */
1139 	if (pat_works) {
1140 		if (pat_idx == 4)
1141 			pat_idx = 0;
1142 		if (pat_idx == 7)
1143 			pat_idx = 3;
1144 	} else {
1145 		/* XXXKIB */
1146 	}
1147 
1148 	return (pat_idx);
1149 }
1150 
1151 static bool
__CONCAT(PMTYPE,ps_enabled)1152 __CONCAT(PMTYPE, ps_enabled)(pmap_t pmap __unused)
1153 {
1154 
1155 	return (pg_ps_enabled);
1156 }
1157 
1158 /*
1159  * The caller is responsible for maintaining TLB consistency.
1160  */
1161 static void
pmap_kenter_pde(vm_offset_t va,pd_entry_t newpde)1162 pmap_kenter_pde(vm_offset_t va, pd_entry_t newpde)
1163 {
1164 	pd_entry_t *pde;
1165 
1166 	pde = pmap_pde(kernel_pmap, va);
1167 	pde_store(pde, newpde);
1168 }
1169 
1170 /*
1171  * After changing the page size for the specified virtual address in the page
1172  * table, flush the corresponding entries from the processor's TLB.  Only the
1173  * calling processor's TLB is affected.
1174  *
1175  * The calling thread must be pinned to a processor.
1176  */
1177 static void
pmap_update_pde_invalidate(vm_offset_t va,pd_entry_t newpde)1178 pmap_update_pde_invalidate(vm_offset_t va, pd_entry_t newpde)
1179 {
1180 
1181 	if ((newpde & PG_PS) == 0)
1182 		/* Demotion: flush a specific 2MB page mapping. */
1183 		invlpg(va);
1184 	else /* if ((newpde & PG_G) == 0) */
1185 		/*
1186 		 * Promotion: flush every 4KB page mapping from the TLB
1187 		 * because there are too many to flush individually.
1188 		 */
1189 		invltlb();
1190 }
1191 
1192 #ifdef SMP
1193 
1194 static void
pmap_curcpu_cb_dummy(pmap_t pmap __unused,vm_offset_t addr1 __unused,vm_offset_t addr2 __unused)1195 pmap_curcpu_cb_dummy(pmap_t pmap __unused, vm_offset_t addr1 __unused,
1196     vm_offset_t addr2 __unused)
1197 {
1198 }
1199 
1200 /*
1201  * For SMP, these functions have to use the IPI mechanism for coherence.
1202  *
1203  * N.B.: Before calling any of the following TLB invalidation functions,
1204  * the calling processor must ensure that all stores updating a non-
1205  * kernel page table are globally performed.  Otherwise, another
1206  * processor could cache an old, pre-update entry without being
1207  * invalidated.  This can happen one of two ways: (1) The pmap becomes
1208  * active on another processor after its pm_active field is checked by
1209  * one of the following functions but before a store updating the page
1210  * table is globally performed. (2) The pmap becomes active on another
1211  * processor before its pm_active field is checked but due to
1212  * speculative loads one of the following functions stills reads the
1213  * pmap as inactive on the other processor.
1214  *
1215  * The kernel page table is exempt because its pm_active field is
1216  * immutable.  The kernel page table is always active on every
1217  * processor.
1218  */
1219 static void
pmap_invalidate_page_int(pmap_t pmap,vm_offset_t va)1220 pmap_invalidate_page_int(pmap_t pmap, vm_offset_t va)
1221 {
1222 	cpuset_t *mask, other_cpus;
1223 	u_int cpuid;
1224 
1225 	sched_pin();
1226 	if (pmap == kernel_pmap) {
1227 		invlpg(va);
1228 		mask = &all_cpus;
1229 	} else if (!CPU_CMP(&pmap->pm_active, &all_cpus)) {
1230 		mask = &all_cpus;
1231 	} else {
1232 		cpuid = PCPU_GET(cpuid);
1233 		other_cpus = all_cpus;
1234 		CPU_CLR(cpuid, &other_cpus);
1235 		CPU_AND(&other_cpus, &other_cpus, &pmap->pm_active);
1236 		mask = &other_cpus;
1237 	}
1238 	smp_masked_invlpg(*mask, va, pmap, pmap_curcpu_cb_dummy);
1239 	sched_unpin();
1240 }
1241 
1242 /* 4k PTEs -- Chosen to exceed the total size of Broadwell L2 TLB */
1243 #define	PMAP_INVLPG_THRESHOLD	(4 * 1024 * PAGE_SIZE)
1244 
1245 static void
pmap_invalidate_range_int(pmap_t pmap,vm_offset_t sva,vm_offset_t eva)1246 pmap_invalidate_range_int(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
1247 {
1248 	cpuset_t *mask, other_cpus;
1249 	vm_offset_t addr;
1250 	u_int cpuid;
1251 
1252 	if (eva - sva >= PMAP_INVLPG_THRESHOLD) {
1253 		pmap_invalidate_all_int(pmap);
1254 		return;
1255 	}
1256 
1257 	sched_pin();
1258 	if (pmap == kernel_pmap) {
1259 		for (addr = sva; addr < eva; addr += PAGE_SIZE)
1260 			invlpg(addr);
1261 		mask = &all_cpus;
1262 	} else  if (!CPU_CMP(&pmap->pm_active, &all_cpus)) {
1263 		mask = &all_cpus;
1264 	} else {
1265 		cpuid = PCPU_GET(cpuid);
1266 		other_cpus = all_cpus;
1267 		CPU_CLR(cpuid, &other_cpus);
1268 		CPU_AND(&other_cpus, &other_cpus, &pmap->pm_active);
1269 		mask = &other_cpus;
1270 	}
1271 	smp_masked_invlpg_range(*mask, sva, eva, pmap, pmap_curcpu_cb_dummy);
1272 	sched_unpin();
1273 }
1274 
1275 static void
pmap_invalidate_all_int(pmap_t pmap)1276 pmap_invalidate_all_int(pmap_t pmap)
1277 {
1278 	cpuset_t *mask, other_cpus;
1279 	u_int cpuid;
1280 
1281 	sched_pin();
1282 	if (pmap == kernel_pmap) {
1283 		invltlb();
1284 		mask = &all_cpus;
1285 	} else if (!CPU_CMP(&pmap->pm_active, &all_cpus)) {
1286 		mask = &all_cpus;
1287 	} else {
1288 		cpuid = PCPU_GET(cpuid);
1289 		other_cpus = all_cpus;
1290 		CPU_CLR(cpuid, &other_cpus);
1291 		CPU_AND(&other_cpus, &other_cpus, &pmap->pm_active);
1292 		mask = &other_cpus;
1293 	}
1294 	smp_masked_invltlb(*mask, pmap, pmap_curcpu_cb_dummy);
1295 	sched_unpin();
1296 }
1297 
1298 static void
pmap_invalidate_cache_curcpu_cb(pmap_t pmap __unused,vm_offset_t addr1 __unused,vm_offset_t addr2 __unused)1299 pmap_invalidate_cache_curcpu_cb(pmap_t pmap __unused,
1300     vm_offset_t addr1 __unused, vm_offset_t addr2 __unused)
1301 {
1302 	wbinvd();
1303 }
1304 
1305 static void
__CONCAT(PMTYPE,invalidate_cache)1306 __CONCAT(PMTYPE, invalidate_cache)(void)
1307 {
1308 	smp_cache_flush(pmap_invalidate_cache_curcpu_cb);
1309 }
1310 
1311 struct pde_action {
1312 	cpuset_t invalidate;	/* processors that invalidate their TLB */
1313 	vm_offset_t va;
1314 	pd_entry_t *pde;
1315 	pd_entry_t newpde;
1316 	u_int store;		/* processor that updates the PDE */
1317 };
1318 
1319 static void
pmap_update_pde_kernel(void * arg)1320 pmap_update_pde_kernel(void *arg)
1321 {
1322 	struct pde_action *act = arg;
1323 	pd_entry_t *pde;
1324 
1325 	if (act->store == PCPU_GET(cpuid)) {
1326 		pde = pmap_pde(kernel_pmap, act->va);
1327 		pde_store(pde, act->newpde);
1328 	}
1329 }
1330 
1331 static void
pmap_update_pde_user(void * arg)1332 pmap_update_pde_user(void *arg)
1333 {
1334 	struct pde_action *act = arg;
1335 
1336 	if (act->store == PCPU_GET(cpuid))
1337 		pde_store(act->pde, act->newpde);
1338 }
1339 
1340 static void
pmap_update_pde_teardown(void * arg)1341 pmap_update_pde_teardown(void *arg)
1342 {
1343 	struct pde_action *act = arg;
1344 
1345 	if (CPU_ISSET(PCPU_GET(cpuid), &act->invalidate))
1346 		pmap_update_pde_invalidate(act->va, act->newpde);
1347 }
1348 
1349 /*
1350  * Change the page size for the specified virtual address in a way that
1351  * prevents any possibility of the TLB ever having two entries that map the
1352  * same virtual address using different page sizes.  This is the recommended
1353  * workaround for Erratum 383 on AMD Family 10h processors.  It prevents a
1354  * machine check exception for a TLB state that is improperly diagnosed as a
1355  * hardware error.
1356  */
1357 static void
pmap_update_pde(pmap_t pmap,vm_offset_t va,pd_entry_t * pde,pd_entry_t newpde)1358 pmap_update_pde(pmap_t pmap, vm_offset_t va, pd_entry_t *pde, pd_entry_t newpde)
1359 {
1360 	struct pde_action act;
1361 	cpuset_t active, other_cpus;
1362 	u_int cpuid;
1363 
1364 	sched_pin();
1365 	cpuid = PCPU_GET(cpuid);
1366 	other_cpus = all_cpus;
1367 	CPU_CLR(cpuid, &other_cpus);
1368 	if (pmap == kernel_pmap)
1369 		active = all_cpus;
1370 	else
1371 		active = pmap->pm_active;
1372 	if (CPU_OVERLAP(&active, &other_cpus)) {
1373 		act.store = cpuid;
1374 		act.invalidate = active;
1375 		act.va = va;
1376 		act.pde = pde;
1377 		act.newpde = newpde;
1378 		CPU_SET(cpuid, &active);
1379 		smp_rendezvous_cpus(active,
1380 		    smp_no_rendezvous_barrier, pmap == kernel_pmap ?
1381 		    pmap_update_pde_kernel : pmap_update_pde_user,
1382 		    pmap_update_pde_teardown, &act);
1383 	} else {
1384 		if (pmap == kernel_pmap)
1385 			pmap_kenter_pde(va, newpde);
1386 		else
1387 			pde_store(pde, newpde);
1388 		if (CPU_ISSET(cpuid, &active))
1389 			pmap_update_pde_invalidate(va, newpde);
1390 	}
1391 	sched_unpin();
1392 }
1393 #else /* !SMP */
1394 /*
1395  * Normal, non-SMP, 486+ invalidation functions.
1396  * We inline these within pmap.c for speed.
1397  */
1398 static void
pmap_invalidate_page_int(pmap_t pmap,vm_offset_t va)1399 pmap_invalidate_page_int(pmap_t pmap, vm_offset_t va)
1400 {
1401 
1402 	if (pmap == kernel_pmap)
1403 		invlpg(va);
1404 }
1405 
1406 static void
pmap_invalidate_range_int(pmap_t pmap,vm_offset_t sva,vm_offset_t eva)1407 pmap_invalidate_range_int(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
1408 {
1409 	vm_offset_t addr;
1410 
1411 	if (pmap == kernel_pmap)
1412 		for (addr = sva; addr < eva; addr += PAGE_SIZE)
1413 			invlpg(addr);
1414 }
1415 
1416 static void
pmap_invalidate_all_int(pmap_t pmap)1417 pmap_invalidate_all_int(pmap_t pmap)
1418 {
1419 
1420 	if (pmap == kernel_pmap)
1421 		invltlb();
1422 }
1423 
1424 static void
__CONCAT(PMTYPE,invalidate_cache)1425 __CONCAT(PMTYPE, invalidate_cache)(void)
1426 {
1427 
1428 	wbinvd();
1429 }
1430 
1431 static void
pmap_update_pde(pmap_t pmap,vm_offset_t va,pd_entry_t * pde,pd_entry_t newpde)1432 pmap_update_pde(pmap_t pmap, vm_offset_t va, pd_entry_t *pde, pd_entry_t newpde)
1433 {
1434 
1435 	if (pmap == kernel_pmap)
1436 		pmap_kenter_pde(va, newpde);
1437 	else
1438 		pde_store(pde, newpde);
1439 	if (pmap == kernel_pmap || !CPU_EMPTY(&pmap->pm_active))
1440 		pmap_update_pde_invalidate(va, newpde);
1441 }
1442 #endif /* !SMP */
1443 
1444 static void
__CONCAT(PMTYPE,invalidate_page)1445 __CONCAT(PMTYPE, invalidate_page)(pmap_t pmap, vm_offset_t va)
1446 {
1447 
1448 	pmap_invalidate_page_int(pmap, va);
1449 }
1450 
1451 static void
__CONCAT(PMTYPE,invalidate_range)1452 __CONCAT(PMTYPE, invalidate_range)(pmap_t pmap, vm_offset_t sva,
1453     vm_offset_t eva)
1454 {
1455 
1456 	pmap_invalidate_range_int(pmap, sva, eva);
1457 }
1458 
1459 static void
__CONCAT(PMTYPE,invalidate_all)1460 __CONCAT(PMTYPE, invalidate_all)(pmap_t pmap)
1461 {
1462 
1463 	pmap_invalidate_all_int(pmap);
1464 }
1465 
1466 static void
pmap_invalidate_pde_page(pmap_t pmap,vm_offset_t va,pd_entry_t pde)1467 pmap_invalidate_pde_page(pmap_t pmap, vm_offset_t va, pd_entry_t pde)
1468 {
1469 
1470 	/*
1471 	 * When the PDE has PG_PROMOTED set, the 2- or 4MB page mapping was
1472 	 * created by a promotion that did not invalidate the 512 or 1024 4KB
1473 	 * page mappings that might exist in the TLB.  Consequently, at this
1474 	 * point, the TLB may hold both 4KB and 2- or 4MB page mappings for
1475 	 * the address range [va, va + NBPDR).  Therefore, the entire range
1476 	 * must be invalidated here.  In contrast, when PG_PROMOTED is clear,
1477 	 * the TLB will not hold any 4KB page mappings for the address range
1478 	 * [va, va + NBPDR), and so a single INVLPG suffices to invalidate the
1479 	 * 2- or 4MB page mapping from the TLB.
1480 	 */
1481 	if ((pde & PG_PROMOTED) != 0)
1482 		pmap_invalidate_range_int(pmap, va, va + NBPDR - 1);
1483 	else
1484 		pmap_invalidate_page_int(pmap, va);
1485 }
1486 
1487 /*
1488  * Are we current address space or kernel?
1489  */
1490 static __inline int
pmap_is_current(pmap_t pmap)1491 pmap_is_current(pmap_t pmap)
1492 {
1493 
1494 	return (pmap == kernel_pmap);
1495 }
1496 
1497 /*
1498  * If the given pmap is not the current or kernel pmap, the returned pte must
1499  * be released by passing it to pmap_pte_release().
1500  */
1501 static pt_entry_t *
__CONCAT(PMTYPE,pte)1502 __CONCAT(PMTYPE, pte)(pmap_t pmap, vm_offset_t va)
1503 {
1504 	pd_entry_t newpf;
1505 	pd_entry_t *pde;
1506 
1507 	pde = pmap_pde(pmap, va);
1508 	if (*pde & PG_PS)
1509 		return (pde);
1510 	if (*pde != 0) {
1511 		/* are we current address space or kernel? */
1512 		if (pmap_is_current(pmap))
1513 			return (vtopte(va));
1514 		mtx_lock(&PMAP2mutex);
1515 		newpf = *pde & PG_FRAME;
1516 		if ((*PMAP2 & PG_FRAME) != newpf) {
1517 			*PMAP2 = newpf | PG_RW | PG_V | PG_A | PG_M;
1518 			pmap_invalidate_page_int(kernel_pmap,
1519 			    (vm_offset_t)PADDR2);
1520 		}
1521 		return (PADDR2 + (i386_btop(va) & (NPTEPG - 1)));
1522 	}
1523 	return (NULL);
1524 }
1525 
1526 /*
1527  * Releases a pte that was obtained from pmap_pte().  Be prepared for the pte
1528  * being NULL.
1529  */
1530 static __inline void
pmap_pte_release(pt_entry_t * pte)1531 pmap_pte_release(pt_entry_t *pte)
1532 {
1533 
1534 	if ((pt_entry_t *)((vm_offset_t)pte & ~PAGE_MASK) == PADDR2)
1535 		mtx_unlock(&PMAP2mutex);
1536 }
1537 
1538 /*
1539  * NB:  The sequence of updating a page table followed by accesses to the
1540  * corresponding pages is subject to the situation described in the "AMD64
1541  * Architecture Programmer's Manual Volume 2: System Programming" rev. 3.23,
1542  * "7.3.1 Special Coherency Considerations".  Therefore, issuing the INVLPG
1543  * right after modifying the PTE bits is crucial.
1544  */
1545 static __inline void
invlcaddr(void * caddr)1546 invlcaddr(void *caddr)
1547 {
1548 
1549 	invlpg((u_int)caddr);
1550 }
1551 
1552 /*
1553  * Super fast pmap_pte routine best used when scanning
1554  * the pv lists.  This eliminates many coarse-grained
1555  * invltlb calls.  Note that many of the pv list
1556  * scans are across different pmaps.  It is very wasteful
1557  * to do an entire invltlb for checking a single mapping.
1558  *
1559  * If the given pmap is not the current pmap, pvh_global_lock
1560  * must be held and curthread pinned to a CPU.
1561  */
1562 static pt_entry_t *
pmap_pte_quick(pmap_t pmap,vm_offset_t va)1563 pmap_pte_quick(pmap_t pmap, vm_offset_t va)
1564 {
1565 	pd_entry_t newpf;
1566 	pd_entry_t *pde;
1567 
1568 	pde = pmap_pde(pmap, va);
1569 	if (*pde & PG_PS)
1570 		return (pde);
1571 	if (*pde != 0) {
1572 		/* are we current address space or kernel? */
1573 		if (pmap_is_current(pmap))
1574 			return (vtopte(va));
1575 		rw_assert(&pvh_global_lock, RA_WLOCKED);
1576 		KASSERT(curthread->td_pinned > 0, ("curthread not pinned"));
1577 		newpf = *pde & PG_FRAME;
1578 		if ((*PMAP1 & PG_FRAME) != newpf) {
1579 			*PMAP1 = newpf | PG_RW | PG_V | PG_A | PG_M;
1580 #ifdef SMP
1581 			PMAP1cpu = PCPU_GET(cpuid);
1582 #endif
1583 			invlcaddr(PADDR1);
1584 			PMAP1changed++;
1585 		} else
1586 #ifdef SMP
1587 		if (PMAP1cpu != PCPU_GET(cpuid)) {
1588 			PMAP1cpu = PCPU_GET(cpuid);
1589 			invlcaddr(PADDR1);
1590 			PMAP1changedcpu++;
1591 		} else
1592 #endif
1593 			PMAP1unchanged++;
1594 		return (PADDR1 + (i386_btop(va) & (NPTEPG - 1)));
1595 	}
1596 	return (0);
1597 }
1598 
1599 static pt_entry_t *
pmap_pte_quick3(pmap_t pmap,vm_offset_t va)1600 pmap_pte_quick3(pmap_t pmap, vm_offset_t va)
1601 {
1602 	pd_entry_t newpf;
1603 	pd_entry_t *pde;
1604 
1605 	pde = pmap_pde(pmap, va);
1606 	if (*pde & PG_PS)
1607 		return (pde);
1608 	if (*pde != 0) {
1609 		rw_assert(&pvh_global_lock, RA_WLOCKED);
1610 		KASSERT(curthread->td_pinned > 0, ("curthread not pinned"));
1611 		newpf = *pde & PG_FRAME;
1612 		if ((*PMAP3 & PG_FRAME) != newpf) {
1613 			*PMAP3 = newpf | PG_RW | PG_V | PG_A | PG_M;
1614 #ifdef SMP
1615 			PMAP3cpu = PCPU_GET(cpuid);
1616 #endif
1617 			invlcaddr(PADDR3);
1618 			PMAP1changed++;
1619 		} else
1620 #ifdef SMP
1621 		if (PMAP3cpu != PCPU_GET(cpuid)) {
1622 			PMAP3cpu = PCPU_GET(cpuid);
1623 			invlcaddr(PADDR3);
1624 			PMAP1changedcpu++;
1625 		} else
1626 #endif
1627 			PMAP1unchanged++;
1628 		return (PADDR3 + (i386_btop(va) & (NPTEPG - 1)));
1629 	}
1630 	return (0);
1631 }
1632 
1633 static pt_entry_t
pmap_pte_ufast(pmap_t pmap,vm_offset_t va,pd_entry_t pde)1634 pmap_pte_ufast(pmap_t pmap, vm_offset_t va, pd_entry_t pde)
1635 {
1636 	pt_entry_t *eh_ptep, pte, *ptep;
1637 
1638 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
1639 	pde &= PG_FRAME;
1640 	critical_enter();
1641 	eh_ptep = (pt_entry_t *)PCPU_GET(pmap_eh_ptep);
1642 	if ((*eh_ptep & PG_FRAME) != pde) {
1643 		*eh_ptep = pde | PG_RW | PG_V | PG_A | PG_M;
1644 		invlcaddr((void *)PCPU_GET(pmap_eh_va));
1645 	}
1646 	ptep = (pt_entry_t *)PCPU_GET(pmap_eh_va) + (i386_btop(va) &
1647 	    (NPTEPG - 1));
1648 	pte = *ptep;
1649 	critical_exit();
1650 	return (pte);
1651 }
1652 
1653 /*
1654  * Extract from the kernel page table the physical address that is mapped by
1655  * the given virtual address "va".
1656  *
1657  * This function may be used before pmap_bootstrap() is called.
1658  */
1659 static vm_paddr_t
__CONCAT(PMTYPE,kextract)1660 __CONCAT(PMTYPE, kextract)(vm_offset_t va)
1661 {
1662 	vm_paddr_t pa;
1663 
1664 	if ((pa = pte_load(&PTD[va >> PDRSHIFT])) & PG_PS) {
1665 		pa = (pa & PG_PS_FRAME) | (va & PDRMASK);
1666 	} else {
1667 		/*
1668 		 * Beware of a concurrent promotion that changes the PDE at
1669 		 * this point!  For example, vtopte() must not be used to
1670 		 * access the PTE because it would use the new PDE.  It is,
1671 		 * however, safe to use the old PDE because the page table
1672 		 * page is preserved by the promotion.
1673 		 */
1674 		pa = KPTmap[i386_btop(va)];
1675 		pa = (pa & PG_FRAME) | (va & PAGE_MASK);
1676 	}
1677 	return (pa);
1678 }
1679 
1680 /*
1681  *	Routine:	pmap_extract
1682  *	Function:
1683  *		Extract the physical page address associated
1684  *		with the given map/virtual_address pair.
1685  */
1686 static vm_paddr_t
__CONCAT(PMTYPE,extract)1687 __CONCAT(PMTYPE, extract)(pmap_t pmap, vm_offset_t va)
1688 {
1689 	vm_paddr_t rtval;
1690 	pt_entry_t pte;
1691 	pd_entry_t pde;
1692 
1693 	rtval = 0;
1694 	PMAP_LOCK(pmap);
1695 	pde = pmap->pm_pdir[va >> PDRSHIFT];
1696 	if (pde != 0) {
1697 		if ((pde & PG_PS) != 0)
1698 			rtval = (pde & PG_PS_FRAME) | (va & PDRMASK);
1699 		else {
1700 			pte = pmap_pte_ufast(pmap, va, pde);
1701 			rtval = (pte & PG_FRAME) | (va & PAGE_MASK);
1702 		}
1703 	}
1704 	PMAP_UNLOCK(pmap);
1705 	return (rtval);
1706 }
1707 
1708 /*
1709  *	Routine:	pmap_extract_and_hold
1710  *	Function:
1711  *		Atomically extract and hold the physical page
1712  *		with the given pmap and virtual address pair
1713  *		if that mapping permits the given protection.
1714  */
1715 static vm_page_t
__CONCAT(PMTYPE,extract_and_hold)1716 __CONCAT(PMTYPE, extract_and_hold)(pmap_t pmap, vm_offset_t va, vm_prot_t prot)
1717 {
1718 	pd_entry_t pde;
1719 	pt_entry_t pte;
1720 	vm_page_t m;
1721 
1722 	m = NULL;
1723 	PMAP_LOCK(pmap);
1724 	pde = *pmap_pde(pmap, va);
1725 	if (pde != 0) {
1726 		if (pde & PG_PS) {
1727 			if ((pde & PG_RW) || (prot & VM_PROT_WRITE) == 0)
1728 				m = PHYS_TO_VM_PAGE((pde & PG_PS_FRAME) |
1729 				    (va & PDRMASK));
1730 		} else {
1731 			pte = pmap_pte_ufast(pmap, va, pde);
1732 			if (pte != 0 &&
1733 			    ((pte & PG_RW) || (prot & VM_PROT_WRITE) == 0))
1734 				m = PHYS_TO_VM_PAGE(pte & PG_FRAME);
1735 		}
1736 		if (m != NULL && !vm_page_wire_mapped(m))
1737 			m = NULL;
1738 	}
1739 	PMAP_UNLOCK(pmap);
1740 	return (m);
1741 }
1742 
1743 /***************************************************
1744  * Low level mapping routines.....
1745  ***************************************************/
1746 
1747 /*
1748  * Add a wired page to the kva.
1749  * Note: not SMP coherent.
1750  *
1751  * This function may be used before pmap_bootstrap() is called.
1752  */
1753 static void
__CONCAT(PMTYPE,kenter)1754 __CONCAT(PMTYPE, kenter)(vm_offset_t va, vm_paddr_t pa)
1755 {
1756 	pt_entry_t *pte;
1757 
1758 	pte = vtopte(va);
1759 	pte_store(pte, pa | PG_RW | PG_V);
1760 }
1761 
1762 static __inline void
pmap_kenter_attr(vm_offset_t va,vm_paddr_t pa,int mode)1763 pmap_kenter_attr(vm_offset_t va, vm_paddr_t pa, int mode)
1764 {
1765 	pt_entry_t *pte;
1766 
1767 	pte = vtopte(va);
1768 	pte_store(pte, pa | PG_RW | PG_V | pmap_cache_bits(kernel_pmap,
1769 	    mode, false));
1770 }
1771 
1772 /*
1773  * Remove a page from the kernel pagetables.
1774  * Note: not SMP coherent.
1775  *
1776  * This function may be used before pmap_bootstrap() is called.
1777  */
1778 static void
__CONCAT(PMTYPE,kremove)1779 __CONCAT(PMTYPE, kremove)(vm_offset_t va)
1780 {
1781 	pt_entry_t *pte;
1782 
1783 	pte = vtopte(va);
1784 	pte_clear(pte);
1785 }
1786 
1787 /*
1788  *	Used to map a range of physical addresses into kernel
1789  *	virtual address space.
1790  *
1791  *	The value passed in '*virt' is a suggested virtual address for
1792  *	the mapping. Architectures which can support a direct-mapped
1793  *	physical to virtual region can return the appropriate address
1794  *	within that region, leaving '*virt' unchanged. Other
1795  *	architectures should map the pages starting at '*virt' and
1796  *	update '*virt' with the first usable address after the mapped
1797  *	region.
1798  */
1799 static vm_offset_t
__CONCAT(PMTYPE,map)1800 __CONCAT(PMTYPE, map)(vm_offset_t *virt, vm_paddr_t start, vm_paddr_t end,
1801     int prot)
1802 {
1803 	vm_offset_t va, sva;
1804 	vm_paddr_t superpage_offset;
1805 	pd_entry_t newpde;
1806 
1807 	va = *virt;
1808 	/*
1809 	 * Does the physical address range's size and alignment permit at
1810 	 * least one superpage mapping to be created?
1811 	 */
1812 	superpage_offset = start & PDRMASK;
1813 	if ((end - start) - ((NBPDR - superpage_offset) & PDRMASK) >= NBPDR) {
1814 		/*
1815 		 * Increase the starting virtual address so that its alignment
1816 		 * does not preclude the use of superpage mappings.
1817 		 */
1818 		if ((va & PDRMASK) < superpage_offset)
1819 			va = (va & ~PDRMASK) + superpage_offset;
1820 		else if ((va & PDRMASK) > superpage_offset)
1821 			va = ((va + PDRMASK) & ~PDRMASK) + superpage_offset;
1822 	}
1823 	sva = va;
1824 	while (start < end) {
1825 		if ((start & PDRMASK) == 0 && end - start >= NBPDR &&
1826 		    pseflag != 0) {
1827 			KASSERT((va & PDRMASK) == 0,
1828 			    ("pmap_map: misaligned va %#x", va));
1829 			newpde = start | PG_PS | PG_RW | PG_V;
1830 			pmap_kenter_pde(va, newpde);
1831 			va += NBPDR;
1832 			start += NBPDR;
1833 		} else {
1834 			pmap_kenter(va, start);
1835 			va += PAGE_SIZE;
1836 			start += PAGE_SIZE;
1837 		}
1838 	}
1839 	pmap_invalidate_range_int(kernel_pmap, sva, va);
1840 	*virt = va;
1841 	return (sva);
1842 }
1843 
1844 /*
1845  * Add a list of wired pages to the kva
1846  * this routine is only used for temporary
1847  * kernel mappings that do not need to have
1848  * page modification or references recorded.
1849  * Note that old mappings are simply written
1850  * over.  The page *must* be wired.
1851  * Note: SMP coherent.  Uses a ranged shootdown IPI.
1852  */
1853 static void
__CONCAT(PMTYPE,qenter)1854 __CONCAT(PMTYPE, qenter)(vm_offset_t sva, vm_page_t *ma, int count)
1855 {
1856 	pt_entry_t *endpte, oldpte, pa, *pte;
1857 	vm_page_t m;
1858 
1859 	oldpte = 0;
1860 	pte = vtopte(sva);
1861 	endpte = pte + count;
1862 	while (pte < endpte) {
1863 		m = *ma++;
1864 		pa = VM_PAGE_TO_PHYS(m) | pmap_cache_bits(kernel_pmap,
1865 		    m->md.pat_mode, false);
1866 		if ((*pte & (PG_FRAME | PG_PTE_CACHE)) != pa) {
1867 			oldpte |= *pte;
1868 			pte_store(pte, pa | pg_nx | PG_RW | PG_V);
1869 		}
1870 		pte++;
1871 	}
1872 	if (__predict_false((oldpte & PG_V) != 0))
1873 		pmap_invalidate_range_int(kernel_pmap, sva, sva + count *
1874 		    PAGE_SIZE);
1875 }
1876 
1877 /*
1878  * This routine tears out page mappings from the
1879  * kernel -- it is meant only for temporary mappings.
1880  * Note: SMP coherent.  Uses a ranged shootdown IPI.
1881  */
1882 static void
__CONCAT(PMTYPE,qremove)1883 __CONCAT(PMTYPE, qremove)(vm_offset_t sva, int count)
1884 {
1885 	vm_offset_t va;
1886 
1887 	va = sva;
1888 	while (count-- > 0) {
1889 		pmap_kremove(va);
1890 		va += PAGE_SIZE;
1891 	}
1892 	pmap_invalidate_range_int(kernel_pmap, sva, va);
1893 }
1894 
1895 /***************************************************
1896  * Page table page management routines.....
1897  ***************************************************/
1898 /*
1899  * Schedule the specified unused page table page to be freed.  Specifically,
1900  * add the page to the specified list of pages that will be released to the
1901  * physical memory manager after the TLB has been updated.
1902  */
1903 static __inline void
pmap_add_delayed_free_list(vm_page_t m,struct spglist * free,bool set_PG_ZERO)1904 pmap_add_delayed_free_list(vm_page_t m, struct spglist *free, bool set_PG_ZERO)
1905 {
1906 
1907 	if (set_PG_ZERO)
1908 		m->flags |= PG_ZERO;
1909 	else
1910 		m->flags &= ~PG_ZERO;
1911 	SLIST_INSERT_HEAD(free, m, plinks.s.ss);
1912 }
1913 
1914 /*
1915  * Inserts the specified page table page into the specified pmap's collection
1916  * of idle page table pages.  Each of a pmap's page table pages is responsible
1917  * for mapping a distinct range of virtual addresses.  The pmap's collection is
1918  * ordered by this virtual address range.
1919  *
1920  * If "promoted" is false, then the page table page "mpte" must be zero filled;
1921  * "mpte"'s valid field will be set to 0.
1922  *
1923  * If "promoted" is true and "allpte_PG_A_set" is false, then "mpte" must
1924  * contain valid mappings with identical attributes except for PG_A; "mpte"'s
1925  * valid field will be set to 1.
1926  *
1927  * If "promoted" and "allpte_PG_A_set" are both true, then "mpte" must contain
1928  * valid mappings with identical attributes including PG_A; "mpte"'s valid
1929  * field will be set to VM_PAGE_BITS_ALL.
1930  */
1931 static __inline int
pmap_insert_pt_page(pmap_t pmap,vm_page_t mpte,bool promoted,bool allpte_PG_A_set)1932 pmap_insert_pt_page(pmap_t pmap, vm_page_t mpte, bool promoted,
1933     bool allpte_PG_A_set)
1934 {
1935 
1936 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
1937 	KASSERT(promoted || !allpte_PG_A_set,
1938 	    ("a zero-filled PTP can't have PG_A set in every PTE"));
1939 	mpte->valid = promoted ? (allpte_PG_A_set ? VM_PAGE_BITS_ALL : 1) : 0;
1940 	return (vm_radix_insert(&pmap->pm_root, mpte));
1941 }
1942 
1943 /*
1944  * Removes the page table page mapping the specified virtual address from the
1945  * specified pmap's collection of idle page table pages, and returns it.
1946  * Otherwise, returns NULL if there is no page table page corresponding to the
1947  * specified virtual address.
1948  */
1949 static __inline vm_page_t
pmap_remove_pt_page(pmap_t pmap,vm_offset_t va)1950 pmap_remove_pt_page(pmap_t pmap, vm_offset_t va)
1951 {
1952 
1953 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
1954 	return (vm_radix_remove(&pmap->pm_root, va >> PDRSHIFT));
1955 }
1956 
1957 /*
1958  * Decrements a page table page's reference count, which is used to record the
1959  * number of valid page table entries within the page.  If the reference count
1960  * drops to zero, then the page table page is unmapped.  Returns true if the
1961  * page table page was unmapped and false otherwise.
1962  */
1963 static inline bool
pmap_unwire_ptp(pmap_t pmap,vm_page_t m,struct spglist * free)1964 pmap_unwire_ptp(pmap_t pmap, vm_page_t m, struct spglist *free)
1965 {
1966 
1967 	--m->ref_count;
1968 	if (m->ref_count == 0) {
1969 		_pmap_unwire_ptp(pmap, m, free);
1970 		return (true);
1971 	} else
1972 		return (false);
1973 }
1974 
1975 static void
_pmap_unwire_ptp(pmap_t pmap,vm_page_t m,struct spglist * free)1976 _pmap_unwire_ptp(pmap_t pmap, vm_page_t m, struct spglist *free)
1977 {
1978 
1979 	/*
1980 	 * unmap the page table page
1981 	 */
1982 	pmap->pm_pdir[m->pindex] = 0;
1983 	--pmap->pm_stats.resident_count;
1984 
1985 	/*
1986 	 * There is not need to invalidate the recursive mapping since
1987 	 * we never instantiate such mapping for the usermode pmaps,
1988 	 * and never remove page table pages from the kernel pmap.
1989 	 * Put page on a list so that it is released since all TLB
1990 	 * shootdown is done.
1991 	 */
1992 	MPASS(pmap != kernel_pmap);
1993 	pmap_add_delayed_free_list(m, free, true);
1994 }
1995 
1996 /*
1997  * After removing a page table entry, this routine is used to
1998  * conditionally free the page, and manage the reference count.
1999  */
2000 static int
pmap_unuse_pt(pmap_t pmap,vm_offset_t va,struct spglist * free)2001 pmap_unuse_pt(pmap_t pmap, vm_offset_t va, struct spglist *free)
2002 {
2003 	pd_entry_t ptepde;
2004 	vm_page_t mpte;
2005 
2006 	if (pmap == kernel_pmap)
2007 		return (0);
2008 	ptepde = *pmap_pde(pmap, va);
2009 	mpte = PHYS_TO_VM_PAGE(ptepde & PG_FRAME);
2010 	return (pmap_unwire_ptp(pmap, mpte, free));
2011 }
2012 
2013 /*
2014  * Release a page table page reference after a failed attempt to create a
2015  * mapping.
2016  */
2017 static void
pmap_abort_ptp(pmap_t pmap,vm_offset_t va,vm_page_t mpte)2018 pmap_abort_ptp(pmap_t pmap, vm_offset_t va, vm_page_t mpte)
2019 {
2020 	struct spglist free;
2021 
2022 	SLIST_INIT(&free);
2023 	if (pmap_unwire_ptp(pmap, mpte, &free)) {
2024 		/*
2025 		 * Although "va" was never mapped, paging-structure caches
2026 		 * could nonetheless have entries that refer to the freed
2027 		 * page table pages.  Invalidate those entries.
2028 		 */
2029 		pmap_invalidate_page_int(pmap, va);
2030 		vm_page_free_pages_toq(&free, true);
2031 	}
2032 }
2033 
2034 /*
2035  * Initialize the pmap for the swapper process.
2036  */
2037 static void
__CONCAT(PMTYPE,pinit0)2038 __CONCAT(PMTYPE, pinit0)(pmap_t pmap)
2039 {
2040 
2041 	PMAP_LOCK_INIT(pmap);
2042 	pmap->pm_pdir = IdlePTD;
2043 #ifdef PMAP_PAE_COMP
2044 	pmap->pm_pdpt = IdlePDPT;
2045 #endif
2046 	vm_radix_init(&pmap->pm_root);
2047 	CPU_ZERO(&pmap->pm_active);
2048 	TAILQ_INIT(&pmap->pm_pvchunk);
2049 	bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
2050 	pmap_activate_boot(pmap);
2051 }
2052 
2053 /*
2054  * Initialize a preallocated and zeroed pmap structure,
2055  * such as one in a vmspace structure.
2056  */
2057 static int
__CONCAT(PMTYPE,pinit)2058 __CONCAT(PMTYPE, pinit)(pmap_t pmap)
2059 {
2060 	int i;
2061 
2062 	/*
2063 	 * No need to allocate page table space yet but we do need a valid
2064 	 * page directory table.
2065 	 */
2066 	if (pmap->pm_pdir == NULL) {
2067 		pmap->pm_pdir = (pd_entry_t *)kva_alloc(NBPTD);
2068 		if (pmap->pm_pdir == NULL)
2069 			return (0);
2070 #ifdef PMAP_PAE_COMP
2071 		pmap->pm_pdpt = uma_zalloc(pdptzone, M_WAITOK | M_ZERO);
2072 		KASSERT(((vm_offset_t)pmap->pm_pdpt &
2073 		    ((NPGPTD * sizeof(pdpt_entry_t)) - 1)) == 0,
2074 		    ("pmap_pinit: pdpt misaligned"));
2075 		KASSERT(pmap_kextract((vm_offset_t)pmap->pm_pdpt) < (4ULL<<30),
2076 		    ("pmap_pinit: pdpt above 4g"));
2077 #endif
2078 		vm_radix_init(&pmap->pm_root);
2079 	}
2080 	KASSERT(vm_radix_is_empty(&pmap->pm_root),
2081 	    ("pmap_pinit: pmap has reserved page table page(s)"));
2082 
2083 	/*
2084 	 * allocate the page directory page(s)
2085 	 */
2086 	for (i = 0; i < NPGPTD; i++) {
2087 		pmap->pm_ptdpg[i] = vm_page_alloc_noobj(VM_ALLOC_WIRED |
2088 		    VM_ALLOC_ZERO | VM_ALLOC_WAITOK);
2089 #ifdef PMAP_PAE_COMP
2090 		pmap->pm_pdpt[i] = VM_PAGE_TO_PHYS(pmap->pm_ptdpg[i]) | PG_V;
2091 #endif
2092 	}
2093 
2094 	pmap_qenter((vm_offset_t)pmap->pm_pdir, pmap->pm_ptdpg, NPGPTD);
2095 #ifdef PMAP_PAE_COMP
2096 	if ((cpu_feature & CPUID_PAT) == 0) {
2097 		pmap_invalidate_cache_range(
2098 		    trunc_page((vm_offset_t)pmap->pm_pdpt),
2099 		    round_page((vm_offset_t)pmap->pm_pdpt +
2100 		    NPGPTD * sizeof(pdpt_entry_t)));
2101 	}
2102 #endif
2103 
2104 	/* Install the trampoline mapping. */
2105 	pmap->pm_pdir[TRPTDI] = PTD[TRPTDI];
2106 
2107 	CPU_ZERO(&pmap->pm_active);
2108 	TAILQ_INIT(&pmap->pm_pvchunk);
2109 	bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
2110 
2111 	return (1);
2112 }
2113 
2114 /*
2115  * this routine is called if the page table page is not
2116  * mapped correctly.
2117  */
2118 static vm_page_t
_pmap_allocpte(pmap_t pmap,u_int ptepindex,u_int flags)2119 _pmap_allocpte(pmap_t pmap, u_int ptepindex, u_int flags)
2120 {
2121 	vm_paddr_t ptepa;
2122 	vm_page_t m;
2123 
2124 	/*
2125 	 * Allocate a page table page.
2126 	 */
2127 	if ((m = vm_page_alloc_noobj(VM_ALLOC_WIRED | VM_ALLOC_ZERO)) == NULL) {
2128 		if ((flags & PMAP_ENTER_NOSLEEP) == 0) {
2129 			PMAP_UNLOCK(pmap);
2130 			rw_wunlock(&pvh_global_lock);
2131 			vm_wait(NULL);
2132 			rw_wlock(&pvh_global_lock);
2133 			PMAP_LOCK(pmap);
2134 		}
2135 
2136 		/*
2137 		 * Indicate the need to retry.  While waiting, the page table
2138 		 * page may have been allocated.
2139 		 */
2140 		return (NULL);
2141 	}
2142 	m->pindex = ptepindex;
2143 
2144 	/*
2145 	 * Map the pagetable page into the process address space, if
2146 	 * it isn't already there.
2147 	 */
2148 
2149 	pmap->pm_stats.resident_count++;
2150 
2151 	ptepa = VM_PAGE_TO_PHYS(m);
2152 	KASSERT((pmap->pm_pdir[ptepindex] & PG_V) == 0,
2153 	    ("%s: page directory entry %#jx is valid",
2154 	    __func__, (uintmax_t)pmap->pm_pdir[ptepindex]));
2155 	pmap->pm_pdir[ptepindex] =
2156 	    (pd_entry_t)(ptepa | PG_U | PG_RW | PG_V | PG_A | PG_M);
2157 
2158 	return (m);
2159 }
2160 
2161 static vm_page_t
pmap_allocpte(pmap_t pmap,vm_offset_t va,u_int flags)2162 pmap_allocpte(pmap_t pmap, vm_offset_t va, u_int flags)
2163 {
2164 	u_int ptepindex;
2165 	pd_entry_t ptepa;
2166 	vm_page_t m;
2167 
2168 	/*
2169 	 * Calculate pagetable page index
2170 	 */
2171 	ptepindex = va >> PDRSHIFT;
2172 retry:
2173 	/*
2174 	 * Get the page directory entry
2175 	 */
2176 	ptepa = pmap->pm_pdir[ptepindex];
2177 
2178 	/*
2179 	 * This supports switching from a 4MB page to a
2180 	 * normal 4K page.
2181 	 */
2182 	if (ptepa & PG_PS) {
2183 		(void)pmap_demote_pde(pmap, &pmap->pm_pdir[ptepindex], va);
2184 		ptepa = pmap->pm_pdir[ptepindex];
2185 	}
2186 
2187 	/*
2188 	 * If the page table page is mapped, we just increment the
2189 	 * hold count, and activate it.
2190 	 */
2191 	if (ptepa) {
2192 		m = PHYS_TO_VM_PAGE(ptepa & PG_FRAME);
2193 		m->ref_count++;
2194 	} else {
2195 		/*
2196 		 * Here if the pte page isn't mapped, or if it has
2197 		 * been deallocated.
2198 		 */
2199 		m = _pmap_allocpte(pmap, ptepindex, flags);
2200 		if (m == NULL && (flags & PMAP_ENTER_NOSLEEP) == 0)
2201 			goto retry;
2202 	}
2203 	return (m);
2204 }
2205 
2206 /***************************************************
2207 * Pmap allocation/deallocation routines.
2208  ***************************************************/
2209 
2210 /*
2211  * Release any resources held by the given physical map.
2212  * Called when a pmap initialized by pmap_pinit is being released.
2213  * Should only be called if the map contains no valid mappings.
2214  */
2215 static void
__CONCAT(PMTYPE,release)2216 __CONCAT(PMTYPE, release)(pmap_t pmap)
2217 {
2218 	vm_page_t m;
2219 	int i;
2220 
2221 	KASSERT(pmap->pm_stats.resident_count == 0,
2222 	    ("pmap_release: pmap resident count %ld != 0",
2223 	    pmap->pm_stats.resident_count));
2224 	KASSERT(vm_radix_is_empty(&pmap->pm_root),
2225 	    ("pmap_release: pmap has reserved page table page(s)"));
2226 	KASSERT(CPU_EMPTY(&pmap->pm_active),
2227 	    ("releasing active pmap %p", pmap));
2228 
2229 	pmap_qremove((vm_offset_t)pmap->pm_pdir, NPGPTD);
2230 
2231 	for (i = 0; i < NPGPTD; i++) {
2232 		m = pmap->pm_ptdpg[i];
2233 #ifdef PMAP_PAE_COMP
2234 		KASSERT(VM_PAGE_TO_PHYS(m) == (pmap->pm_pdpt[i] & PG_FRAME),
2235 		    ("pmap_release: got wrong ptd page"));
2236 #endif
2237 		vm_page_unwire_noq(m);
2238 		vm_page_free(m);
2239 	}
2240 }
2241 
2242 /*
2243  * grow the number of kernel page table entries, if needed
2244  */
2245 static void
__CONCAT(PMTYPE,growkernel)2246 __CONCAT(PMTYPE, growkernel)(vm_offset_t addr)
2247 {
2248 	vm_paddr_t ptppaddr;
2249 	vm_page_t nkpg;
2250 	pd_entry_t newpdir;
2251 
2252 	mtx_assert(&kernel_map->system_mtx, MA_OWNED);
2253 	addr = roundup2(addr, NBPDR);
2254 	if (addr - 1 >= vm_map_max(kernel_map))
2255 		addr = vm_map_max(kernel_map);
2256 	while (kernel_vm_end < addr) {
2257 		if (pdir_pde(PTD, kernel_vm_end)) {
2258 			kernel_vm_end = (kernel_vm_end + NBPDR) & ~PDRMASK;
2259 			if (kernel_vm_end - 1 >= vm_map_max(kernel_map)) {
2260 				kernel_vm_end = vm_map_max(kernel_map);
2261 				break;
2262 			}
2263 			continue;
2264 		}
2265 
2266 		nkpg = vm_page_alloc_noobj(VM_ALLOC_INTERRUPT | VM_ALLOC_WIRED |
2267 		    VM_ALLOC_ZERO);
2268 		if (nkpg == NULL)
2269 			panic("pmap_growkernel: no memory to grow kernel");
2270 		nkpg->pindex = kernel_vm_end >> PDRSHIFT;
2271 		nkpt++;
2272 
2273 		ptppaddr = VM_PAGE_TO_PHYS(nkpg);
2274 		newpdir = (pd_entry_t) (ptppaddr | PG_V | PG_RW | PG_A | PG_M);
2275 		pdir_pde(KPTD, kernel_vm_end) = newpdir;
2276 
2277 		pmap_kenter_pde(kernel_vm_end, newpdir);
2278 		kernel_vm_end = (kernel_vm_end + NBPDR) & ~PDRMASK;
2279 		if (kernel_vm_end - 1 >= vm_map_max(kernel_map)) {
2280 			kernel_vm_end = vm_map_max(kernel_map);
2281 			break;
2282 		}
2283 	}
2284 }
2285 
2286 /***************************************************
2287  * page management routines.
2288  ***************************************************/
2289 
2290 static const uint32_t pc_freemask[_NPCM] = {
2291 	[0 ... _NPCM - 2] = PC_FREEN,
2292 	[_NPCM - 1] = PC_FREEL
2293 };
2294 
2295 #ifdef PV_STATS
2296 extern int pc_chunk_count, pc_chunk_allocs, pc_chunk_frees, pc_chunk_tryfail;
2297 extern long pv_entry_frees, pv_entry_allocs;
2298 extern int pv_entry_spare;
2299 #endif
2300 
2301 /*
2302  * We are in a serious low memory condition.  Resort to
2303  * drastic measures to free some pages so we can allocate
2304  * another pv entry chunk.
2305  */
2306 static vm_page_t
pmap_pv_reclaim(pmap_t locked_pmap)2307 pmap_pv_reclaim(pmap_t locked_pmap)
2308 {
2309 	struct pch newtail;
2310 	struct pv_chunk *pc;
2311 	struct md_page *pvh;
2312 	pd_entry_t *pde;
2313 	pmap_t pmap;
2314 	pt_entry_t *pte, tpte;
2315 	pv_entry_t pv;
2316 	vm_offset_t va;
2317 	vm_page_t m, m_pc;
2318 	struct spglist free;
2319 	uint32_t inuse;
2320 	int bit, field, freed;
2321 
2322 	PMAP_LOCK_ASSERT(locked_pmap, MA_OWNED);
2323 	pmap = NULL;
2324 	m_pc = NULL;
2325 	SLIST_INIT(&free);
2326 	TAILQ_INIT(&newtail);
2327 	while ((pc = TAILQ_FIRST(&pv_chunks)) != NULL && (pv_vafree == 0 ||
2328 	    SLIST_EMPTY(&free))) {
2329 		TAILQ_REMOVE(&pv_chunks, pc, pc_lru);
2330 		if (pmap != pc->pc_pmap) {
2331 			if (pmap != NULL) {
2332 				pmap_invalidate_all_int(pmap);
2333 				if (pmap != locked_pmap)
2334 					PMAP_UNLOCK(pmap);
2335 			}
2336 			pmap = pc->pc_pmap;
2337 			/* Avoid deadlock and lock recursion. */
2338 			if (pmap > locked_pmap)
2339 				PMAP_LOCK(pmap);
2340 			else if (pmap != locked_pmap && !PMAP_TRYLOCK(pmap)) {
2341 				pmap = NULL;
2342 				TAILQ_INSERT_TAIL(&newtail, pc, pc_lru);
2343 				continue;
2344 			}
2345 		}
2346 
2347 		/*
2348 		 * Destroy every non-wired, 4 KB page mapping in the chunk.
2349 		 */
2350 		freed = 0;
2351 		for (field = 0; field < _NPCM; field++) {
2352 			for (inuse = ~pc->pc_map[field] & pc_freemask[field];
2353 			    inuse != 0; inuse &= ~(1UL << bit)) {
2354 				bit = bsfl(inuse);
2355 				pv = &pc->pc_pventry[field * 32 + bit];
2356 				va = pv->pv_va;
2357 				pde = pmap_pde(pmap, va);
2358 				if ((*pde & PG_PS) != 0)
2359 					continue;
2360 				pte = __CONCAT(PMTYPE, pte)(pmap, va);
2361 				tpte = *pte;
2362 				if ((tpte & PG_W) == 0)
2363 					tpte = pte_load_clear(pte);
2364 				pmap_pte_release(pte);
2365 				if ((tpte & PG_W) != 0)
2366 					continue;
2367 				KASSERT(tpte != 0,
2368 				    ("pmap_pv_reclaim: pmap %p va %x zero pte",
2369 				    pmap, va));
2370 				if ((tpte & PG_G) != 0)
2371 					pmap_invalidate_page_int(pmap, va);
2372 				m = PHYS_TO_VM_PAGE(tpte & PG_FRAME);
2373 				if ((tpte & (PG_M | PG_RW)) == (PG_M | PG_RW))
2374 					vm_page_dirty(m);
2375 				if ((tpte & PG_A) != 0)
2376 					vm_page_aflag_set(m, PGA_REFERENCED);
2377 				TAILQ_REMOVE(&m->md.pv_list, pv, pv_next);
2378 				if (TAILQ_EMPTY(&m->md.pv_list) &&
2379 				    (m->flags & PG_FICTITIOUS) == 0) {
2380 					pvh = pa_to_pvh(VM_PAGE_TO_PHYS(m));
2381 					if (TAILQ_EMPTY(&pvh->pv_list)) {
2382 						vm_page_aflag_clear(m,
2383 						    PGA_WRITEABLE);
2384 					}
2385 				}
2386 				pc->pc_map[field] |= 1UL << bit;
2387 				pmap_unuse_pt(pmap, va, &free);
2388 				freed++;
2389 			}
2390 		}
2391 		if (freed == 0) {
2392 			TAILQ_INSERT_TAIL(&newtail, pc, pc_lru);
2393 			continue;
2394 		}
2395 		/* Every freed mapping is for a 4 KB page. */
2396 		pmap->pm_stats.resident_count -= freed;
2397 		PV_STAT(pv_entry_frees += freed);
2398 		PV_STAT(pv_entry_spare += freed);
2399 		pv_entry_count -= freed;
2400 		TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
2401 		for (field = 0; field < _NPCM; field++)
2402 			if (pc->pc_map[field] != pc_freemask[field]) {
2403 				TAILQ_INSERT_HEAD(&pmap->pm_pvchunk, pc,
2404 				    pc_list);
2405 				TAILQ_INSERT_TAIL(&newtail, pc, pc_lru);
2406 
2407 				/*
2408 				 * One freed pv entry in locked_pmap is
2409 				 * sufficient.
2410 				 */
2411 				if (pmap == locked_pmap)
2412 					goto out;
2413 				break;
2414 			}
2415 		if (field == _NPCM) {
2416 			PV_STAT(pv_entry_spare -= _NPCPV);
2417 			PV_STAT(pc_chunk_count--);
2418 			PV_STAT(pc_chunk_frees++);
2419 			/* Entire chunk is free; return it. */
2420 			m_pc = PHYS_TO_VM_PAGE(pmap_kextract((vm_offset_t)pc));
2421 			pmap_qremove((vm_offset_t)pc, 1);
2422 			pmap_ptelist_free(&pv_vafree, (vm_offset_t)pc);
2423 			break;
2424 		}
2425 	}
2426 out:
2427 	TAILQ_CONCAT(&pv_chunks, &newtail, pc_lru);
2428 	if (pmap != NULL) {
2429 		pmap_invalidate_all_int(pmap);
2430 		if (pmap != locked_pmap)
2431 			PMAP_UNLOCK(pmap);
2432 	}
2433 	if (m_pc == NULL && pv_vafree != 0 && SLIST_EMPTY(&free)) {
2434 		m_pc = SLIST_FIRST(&free);
2435 		SLIST_REMOVE_HEAD(&free, plinks.s.ss);
2436 		/* Recycle a freed page table page. */
2437 		m_pc->ref_count = 1;
2438 	}
2439 	vm_page_free_pages_toq(&free, true);
2440 	return (m_pc);
2441 }
2442 
2443 /*
2444  * free the pv_entry back to the free list
2445  */
2446 static void
free_pv_entry(pmap_t pmap,pv_entry_t pv)2447 free_pv_entry(pmap_t pmap, pv_entry_t pv)
2448 {
2449 	struct pv_chunk *pc;
2450 	int idx, field, bit;
2451 
2452 	rw_assert(&pvh_global_lock, RA_WLOCKED);
2453 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
2454 	PV_STAT(pv_entry_frees++);
2455 	PV_STAT(pv_entry_spare++);
2456 	pv_entry_count--;
2457 	pc = pv_to_chunk(pv);
2458 	idx = pv - &pc->pc_pventry[0];
2459 	field = idx / 32;
2460 	bit = idx % 32;
2461 	pc->pc_map[field] |= 1ul << bit;
2462 	for (idx = 0; idx < _NPCM; idx++)
2463 		if (pc->pc_map[idx] != pc_freemask[idx]) {
2464 			/*
2465 			 * 98% of the time, pc is already at the head of the
2466 			 * list.  If it isn't already, move it to the head.
2467 			 */
2468 			if (__predict_false(TAILQ_FIRST(&pmap->pm_pvchunk) !=
2469 			    pc)) {
2470 				TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
2471 				TAILQ_INSERT_HEAD(&pmap->pm_pvchunk, pc,
2472 				    pc_list);
2473 			}
2474 			return;
2475 		}
2476 	TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
2477 	free_pv_chunk(pc);
2478 }
2479 
2480 static void
free_pv_chunk(struct pv_chunk * pc)2481 free_pv_chunk(struct pv_chunk *pc)
2482 {
2483 	vm_page_t m;
2484 
2485  	TAILQ_REMOVE(&pv_chunks, pc, pc_lru);
2486 	PV_STAT(pv_entry_spare -= _NPCPV);
2487 	PV_STAT(pc_chunk_count--);
2488 	PV_STAT(pc_chunk_frees++);
2489 	/* entire chunk is free, return it */
2490 	m = PHYS_TO_VM_PAGE(pmap_kextract((vm_offset_t)pc));
2491 	pmap_qremove((vm_offset_t)pc, 1);
2492 	vm_page_unwire_noq(m);
2493 	vm_page_free(m);
2494 	pmap_ptelist_free(&pv_vafree, (vm_offset_t)pc);
2495 }
2496 
2497 /*
2498  * get a new pv_entry, allocating a block from the system
2499  * when needed.
2500  */
2501 static pv_entry_t
get_pv_entry(pmap_t pmap,bool try)2502 get_pv_entry(pmap_t pmap, bool try)
2503 {
2504 	static const struct timeval printinterval = { 60, 0 };
2505 	static struct timeval lastprint;
2506 	int bit, field;
2507 	pv_entry_t pv;
2508 	struct pv_chunk *pc;
2509 	vm_page_t m;
2510 
2511 	rw_assert(&pvh_global_lock, RA_WLOCKED);
2512 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
2513 	PV_STAT(pv_entry_allocs++);
2514 	pv_entry_count++;
2515 	if (pv_entry_count > pv_entry_high_water)
2516 		if (ratecheck(&lastprint, &printinterval))
2517 			printf("Approaching the limit on PV entries, consider "
2518 			    "increasing either the vm.pmap.shpgperproc or the "
2519 			    "vm.pmap.pv_entry_max tunable.\n");
2520 retry:
2521 	pc = TAILQ_FIRST(&pmap->pm_pvchunk);
2522 	if (pc != NULL) {
2523 		for (field = 0; field < _NPCM; field++) {
2524 			if (pc->pc_map[field]) {
2525 				bit = bsfl(pc->pc_map[field]);
2526 				break;
2527 			}
2528 		}
2529 		if (field < _NPCM) {
2530 			pv = &pc->pc_pventry[field * 32 + bit];
2531 			pc->pc_map[field] &= ~(1ul << bit);
2532 			/* If this was the last item, move it to tail */
2533 			for (field = 0; field < _NPCM; field++)
2534 				if (pc->pc_map[field] != 0) {
2535 					PV_STAT(pv_entry_spare--);
2536 					return (pv);	/* not full, return */
2537 				}
2538 			TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
2539 			TAILQ_INSERT_TAIL(&pmap->pm_pvchunk, pc, pc_list);
2540 			PV_STAT(pv_entry_spare--);
2541 			return (pv);
2542 		}
2543 	}
2544 	/*
2545 	 * Access to the ptelist "pv_vafree" is synchronized by the pvh
2546 	 * global lock.  If "pv_vafree" is currently non-empty, it will
2547 	 * remain non-empty until pmap_ptelist_alloc() completes.
2548 	 */
2549 	if (pv_vafree == 0 ||
2550 	    (m = vm_page_alloc_noobj(VM_ALLOC_WIRED)) == NULL) {
2551 		if (try) {
2552 			pv_entry_count--;
2553 			PV_STAT(pc_chunk_tryfail++);
2554 			return (NULL);
2555 		}
2556 		m = pmap_pv_reclaim(pmap);
2557 		if (m == NULL)
2558 			goto retry;
2559 	}
2560 	PV_STAT(pc_chunk_count++);
2561 	PV_STAT(pc_chunk_allocs++);
2562 	pc = (struct pv_chunk *)pmap_ptelist_alloc(&pv_vafree);
2563 	pmap_qenter((vm_offset_t)pc, &m, 1);
2564 	pc->pc_pmap = pmap;
2565 	pc->pc_map[0] = pc_freemask[0] & ~1ul;	/* preallocated bit 0 */
2566 	for (field = 1; field < _NPCM; field++)
2567 		pc->pc_map[field] = pc_freemask[field];
2568 	TAILQ_INSERT_TAIL(&pv_chunks, pc, pc_lru);
2569 	pv = &pc->pc_pventry[0];
2570 	TAILQ_INSERT_HEAD(&pmap->pm_pvchunk, pc, pc_list);
2571 	PV_STAT(pv_entry_spare += _NPCPV - 1);
2572 	return (pv);
2573 }
2574 
2575 static __inline pv_entry_t
pmap_pvh_remove(struct md_page * pvh,pmap_t pmap,vm_offset_t va)2576 pmap_pvh_remove(struct md_page *pvh, pmap_t pmap, vm_offset_t va)
2577 {
2578 	pv_entry_t pv;
2579 
2580 	rw_assert(&pvh_global_lock, RA_WLOCKED);
2581 	TAILQ_FOREACH(pv, &pvh->pv_list, pv_next) {
2582 		if (pmap == PV_PMAP(pv) && va == pv->pv_va) {
2583 			TAILQ_REMOVE(&pvh->pv_list, pv, pv_next);
2584 			break;
2585 		}
2586 	}
2587 	return (pv);
2588 }
2589 
2590 static void
pmap_pv_demote_pde(pmap_t pmap,vm_offset_t va,vm_paddr_t pa)2591 pmap_pv_demote_pde(pmap_t pmap, vm_offset_t va, vm_paddr_t pa)
2592 {
2593 	struct md_page *pvh;
2594 	pv_entry_t pv;
2595 	vm_offset_t va_last;
2596 	vm_page_t m;
2597 
2598 	rw_assert(&pvh_global_lock, RA_WLOCKED);
2599 	KASSERT((pa & PDRMASK) == 0,
2600 	    ("pmap_pv_demote_pde: pa is not 4mpage aligned"));
2601 
2602 	/*
2603 	 * Transfer the 4mpage's pv entry for this mapping to the first
2604 	 * page's pv list.
2605 	 */
2606 	pvh = pa_to_pvh(pa);
2607 	va = trunc_4mpage(va);
2608 	pv = pmap_pvh_remove(pvh, pmap, va);
2609 	KASSERT(pv != NULL, ("pmap_pv_demote_pde: pv not found"));
2610 	m = PHYS_TO_VM_PAGE(pa);
2611 	TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_next);
2612 	/* Instantiate the remaining NPTEPG - 1 pv entries. */
2613 	va_last = va + NBPDR - PAGE_SIZE;
2614 	do {
2615 		m++;
2616 		KASSERT((m->oflags & VPO_UNMANAGED) == 0,
2617 		    ("pmap_pv_demote_pde: page %p is not managed", m));
2618 		va += PAGE_SIZE;
2619 		pmap_insert_entry(pmap, va, m);
2620 	} while (va < va_last);
2621 }
2622 
2623 #if VM_NRESERVLEVEL > 0
2624 static void
pmap_pv_promote_pde(pmap_t pmap,vm_offset_t va,vm_paddr_t pa)2625 pmap_pv_promote_pde(pmap_t pmap, vm_offset_t va, vm_paddr_t pa)
2626 {
2627 	struct md_page *pvh;
2628 	pv_entry_t pv;
2629 	vm_offset_t va_last;
2630 	vm_page_t m;
2631 
2632 	rw_assert(&pvh_global_lock, RA_WLOCKED);
2633 	KASSERT((pa & PDRMASK) == 0,
2634 	    ("pmap_pv_promote_pde: pa is not 4mpage aligned"));
2635 
2636 	/*
2637 	 * Transfer the first page's pv entry for this mapping to the
2638 	 * 4mpage's pv list.  Aside from avoiding the cost of a call
2639 	 * to get_pv_entry(), a transfer avoids the possibility that
2640 	 * get_pv_entry() calls pmap_collect() and that pmap_collect()
2641 	 * removes one of the mappings that is being promoted.
2642 	 */
2643 	m = PHYS_TO_VM_PAGE(pa);
2644 	va = trunc_4mpage(va);
2645 	pv = pmap_pvh_remove(&m->md, pmap, va);
2646 	KASSERT(pv != NULL, ("pmap_pv_promote_pde: pv not found"));
2647 	pvh = pa_to_pvh(pa);
2648 	TAILQ_INSERT_TAIL(&pvh->pv_list, pv, pv_next);
2649 	/* Free the remaining NPTEPG - 1 pv entries. */
2650 	va_last = va + NBPDR - PAGE_SIZE;
2651 	do {
2652 		m++;
2653 		va += PAGE_SIZE;
2654 		pmap_pvh_free(&m->md, pmap, va);
2655 	} while (va < va_last);
2656 }
2657 #endif /* VM_NRESERVLEVEL > 0 */
2658 
2659 static void
pmap_pvh_free(struct md_page * pvh,pmap_t pmap,vm_offset_t va)2660 pmap_pvh_free(struct md_page *pvh, pmap_t pmap, vm_offset_t va)
2661 {
2662 	pv_entry_t pv;
2663 
2664 	pv = pmap_pvh_remove(pvh, pmap, va);
2665 	KASSERT(pv != NULL, ("pmap_pvh_free: pv not found"));
2666 	free_pv_entry(pmap, pv);
2667 }
2668 
2669 static void
pmap_remove_entry(pmap_t pmap,vm_page_t m,vm_offset_t va)2670 pmap_remove_entry(pmap_t pmap, vm_page_t m, vm_offset_t va)
2671 {
2672 	struct md_page *pvh;
2673 
2674 	rw_assert(&pvh_global_lock, RA_WLOCKED);
2675 	pmap_pvh_free(&m->md, pmap, va);
2676 	if (TAILQ_EMPTY(&m->md.pv_list) && (m->flags & PG_FICTITIOUS) == 0) {
2677 		pvh = pa_to_pvh(VM_PAGE_TO_PHYS(m));
2678 		if (TAILQ_EMPTY(&pvh->pv_list))
2679 			vm_page_aflag_clear(m, PGA_WRITEABLE);
2680 	}
2681 }
2682 
2683 /*
2684  * Create a pv entry for page at pa for
2685  * (pmap, va).
2686  */
2687 static void
pmap_insert_entry(pmap_t pmap,vm_offset_t va,vm_page_t m)2688 pmap_insert_entry(pmap_t pmap, vm_offset_t va, vm_page_t m)
2689 {
2690 	pv_entry_t pv;
2691 
2692 	rw_assert(&pvh_global_lock, RA_WLOCKED);
2693 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
2694 	pv = get_pv_entry(pmap, false);
2695 	pv->pv_va = va;
2696 	TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_next);
2697 }
2698 
2699 /*
2700  * Conditionally create a pv entry.
2701  */
2702 static bool
pmap_try_insert_pv_entry(pmap_t pmap,vm_offset_t va,vm_page_t m)2703 pmap_try_insert_pv_entry(pmap_t pmap, vm_offset_t va, vm_page_t m)
2704 {
2705 	pv_entry_t pv;
2706 
2707 	rw_assert(&pvh_global_lock, RA_WLOCKED);
2708 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
2709 	if (pv_entry_count < pv_entry_high_water &&
2710 	    (pv = get_pv_entry(pmap, true)) != NULL) {
2711 		pv->pv_va = va;
2712 		TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_next);
2713 		return (true);
2714 	} else
2715 		return (false);
2716 }
2717 
2718 /*
2719  * Create the pv entries for each of the pages within a superpage.
2720  */
2721 static bool
pmap_pv_insert_pde(pmap_t pmap,vm_offset_t va,pd_entry_t pde,u_int flags)2722 pmap_pv_insert_pde(pmap_t pmap, vm_offset_t va, pd_entry_t pde, u_int flags)
2723 {
2724 	struct md_page *pvh;
2725 	pv_entry_t pv;
2726 	bool noreclaim;
2727 
2728 	rw_assert(&pvh_global_lock, RA_WLOCKED);
2729 	noreclaim = (flags & PMAP_ENTER_NORECLAIM) != 0;
2730 	if ((noreclaim && pv_entry_count >= pv_entry_high_water) ||
2731 	    (pv = get_pv_entry(pmap, noreclaim)) == NULL)
2732 		return (false);
2733 	pv->pv_va = va;
2734 	pvh = pa_to_pvh(pde & PG_PS_FRAME);
2735 	TAILQ_INSERT_TAIL(&pvh->pv_list, pv, pv_next);
2736 	return (true);
2737 }
2738 
2739 /*
2740  * Fills a page table page with mappings to consecutive physical pages.
2741  */
2742 static void
pmap_fill_ptp(pt_entry_t * firstpte,pt_entry_t newpte)2743 pmap_fill_ptp(pt_entry_t *firstpte, pt_entry_t newpte)
2744 {
2745 	pt_entry_t *pte;
2746 
2747 	for (pte = firstpte; pte < firstpte + NPTEPG; pte++) {
2748 		*pte = newpte;
2749 		newpte += PAGE_SIZE;
2750 	}
2751 }
2752 
2753 /*
2754  * Tries to demote a 2- or 4MB page mapping.  If demotion fails, the
2755  * 2- or 4MB page mapping is invalidated.
2756  */
2757 static bool
pmap_demote_pde(pmap_t pmap,pd_entry_t * pde,vm_offset_t va)2758 pmap_demote_pde(pmap_t pmap, pd_entry_t *pde, vm_offset_t va)
2759 {
2760 	pd_entry_t newpde, oldpde;
2761 	pt_entry_t *firstpte, newpte;
2762 	vm_paddr_t mptepa;
2763 	vm_page_t mpte;
2764 	struct spglist free;
2765 	vm_offset_t sva;
2766 
2767 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
2768 	oldpde = *pde;
2769 	KASSERT((oldpde & (PG_PS | PG_V)) == (PG_PS | PG_V),
2770 	    ("pmap_demote_pde: oldpde is missing PG_PS and/or PG_V"));
2771 	if ((oldpde & PG_A) == 0 || (mpte = pmap_remove_pt_page(pmap, va)) ==
2772 	    NULL) {
2773 		KASSERT((oldpde & PG_W) == 0,
2774 		    ("pmap_demote_pde: page table page for a wired mapping"
2775 		    " is missing"));
2776 
2777 		/*
2778 		 * Invalidate the 2- or 4MB page mapping and return
2779 		 * "failure" if the mapping was never accessed or the
2780 		 * allocation of the new page table page fails.
2781 		 */
2782 		if ((oldpde & PG_A) == 0 ||
2783 		    (mpte = vm_page_alloc_noobj(VM_ALLOC_WIRED)) == NULL) {
2784 			SLIST_INIT(&free);
2785 			sva = trunc_4mpage(va);
2786 			pmap_remove_pde(pmap, pde, sva, &free);
2787 			if ((oldpde & PG_G) == 0)
2788 				pmap_invalidate_pde_page(pmap, sva, oldpde);
2789 			vm_page_free_pages_toq(&free, true);
2790 			CTR2(KTR_PMAP, "pmap_demote_pde: failure for va %#x"
2791 			    " in pmap %p", va, pmap);
2792 			return (false);
2793 		}
2794 		mpte->pindex = va >> PDRSHIFT;
2795 		if (pmap != kernel_pmap) {
2796 			mpte->ref_count = NPTEPG;
2797 			pmap->pm_stats.resident_count++;
2798 		}
2799 	}
2800 	mptepa = VM_PAGE_TO_PHYS(mpte);
2801 
2802 	/*
2803 	 * If the page mapping is in the kernel's address space, then the
2804 	 * KPTmap can provide access to the page table page.  Otherwise,
2805 	 * temporarily map the page table page (mpte) into the kernel's
2806 	 * address space at either PADDR1 or PADDR2.
2807 	 */
2808 	if (pmap == kernel_pmap)
2809 		firstpte = &KPTmap[i386_btop(trunc_4mpage(va))];
2810 	else if (curthread->td_pinned > 0 && rw_wowned(&pvh_global_lock)) {
2811 		if ((*PMAP1 & PG_FRAME) != mptepa) {
2812 			*PMAP1 = mptepa | PG_RW | PG_V | PG_A | PG_M;
2813 #ifdef SMP
2814 			PMAP1cpu = PCPU_GET(cpuid);
2815 #endif
2816 			invlcaddr(PADDR1);
2817 			PMAP1changed++;
2818 		} else
2819 #ifdef SMP
2820 		if (PMAP1cpu != PCPU_GET(cpuid)) {
2821 			PMAP1cpu = PCPU_GET(cpuid);
2822 			invlcaddr(PADDR1);
2823 			PMAP1changedcpu++;
2824 		} else
2825 #endif
2826 			PMAP1unchanged++;
2827 		firstpte = PADDR1;
2828 	} else {
2829 		mtx_lock(&PMAP2mutex);
2830 		if ((*PMAP2 & PG_FRAME) != mptepa) {
2831 			*PMAP2 = mptepa | PG_RW | PG_V | PG_A | PG_M;
2832 			pmap_invalidate_page_int(kernel_pmap,
2833 			    (vm_offset_t)PADDR2);
2834 		}
2835 		firstpte = PADDR2;
2836 	}
2837 	newpde = mptepa | PG_M | PG_A | (oldpde & PG_U) | PG_RW | PG_V;
2838 	KASSERT((oldpde & PG_A) != 0,
2839 	    ("pmap_demote_pde: oldpde is missing PG_A"));
2840 	KASSERT((oldpde & (PG_M | PG_RW)) != PG_RW,
2841 	    ("pmap_demote_pde: oldpde is missing PG_M"));
2842 	newpte = oldpde & ~PG_PS;
2843 	if ((newpte & PG_PDE_PAT) != 0)
2844 		newpte ^= PG_PDE_PAT | PG_PTE_PAT;
2845 
2846 	/*
2847 	 * If the PTP is not leftover from an earlier promotion or it does not
2848 	 * have PG_A set in every PTE, then fill it.  The new PTEs will all
2849 	 * have PG_A set.
2850 	 */
2851 	if (!vm_page_all_valid(mpte))
2852 		pmap_fill_ptp(firstpte, newpte);
2853 
2854 	KASSERT((*firstpte & PG_FRAME) == (newpte & PG_FRAME),
2855 	    ("pmap_demote_pde: firstpte and newpte map different physical"
2856 	    " addresses"));
2857 
2858 	/*
2859 	 * If the mapping has changed attributes, update the PTEs.
2860 	 */
2861 	if ((*firstpte & PG_PTE_PROMOTE) != (newpte & PG_PTE_PROMOTE))
2862 		pmap_fill_ptp(firstpte, newpte);
2863 
2864 	/*
2865 	 * Demote the mapping.  This pmap is locked.  The old PDE has
2866 	 * PG_A set.  If the old PDE has PG_RW set, it also has PG_M
2867 	 * set.  Thus, there is no danger of a race with another
2868 	 * processor changing the setting of PG_A and/or PG_M between
2869 	 * the read above and the store below.
2870 	 */
2871 	if (workaround_erratum383)
2872 		pmap_update_pde(pmap, va, pde, newpde);
2873 	else if (pmap == kernel_pmap)
2874 		pmap_kenter_pde(va, newpde);
2875 	else
2876 		pde_store(pde, newpde);
2877 	if (firstpte == PADDR2)
2878 		mtx_unlock(&PMAP2mutex);
2879 
2880 	/*
2881 	 * Invalidate the recursive mapping of the page table page.
2882 	 */
2883 	pmap_invalidate_page_int(pmap, (vm_offset_t)vtopte(va));
2884 
2885 	/*
2886 	 * Demote the pv entry.  This depends on the earlier demotion
2887 	 * of the mapping.  Specifically, the (re)creation of a per-
2888 	 * page pv entry might trigger the execution of pmap_collect(),
2889 	 * which might reclaim a newly (re)created per-page pv entry
2890 	 * and destroy the associated mapping.  In order to destroy
2891 	 * the mapping, the PDE must have already changed from mapping
2892 	 * the 2mpage to referencing the page table page.
2893 	 */
2894 	if ((oldpde & PG_MANAGED) != 0)
2895 		pmap_pv_demote_pde(pmap, va, oldpde & PG_PS_FRAME);
2896 
2897 	pmap_pde_demotions++;
2898 	CTR2(KTR_PMAP, "pmap_demote_pde: success for va %#x"
2899 	    " in pmap %p", va, pmap);
2900 	return (true);
2901 }
2902 
2903 /*
2904  * Removes a 2- or 4MB page mapping from the kernel pmap.
2905  */
2906 static void
pmap_remove_kernel_pde(pmap_t pmap,pd_entry_t * pde,vm_offset_t va)2907 pmap_remove_kernel_pde(pmap_t pmap, pd_entry_t *pde, vm_offset_t va)
2908 {
2909 	pd_entry_t newpde;
2910 	vm_paddr_t mptepa;
2911 	vm_page_t mpte;
2912 
2913 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
2914 	mpte = pmap_remove_pt_page(pmap, va);
2915 	if (mpte == NULL)
2916 		panic("pmap_remove_kernel_pde: Missing pt page.");
2917 
2918 	mptepa = VM_PAGE_TO_PHYS(mpte);
2919 	newpde = mptepa | PG_M | PG_A | PG_RW | PG_V;
2920 
2921 	/*
2922 	 * If this page table page was unmapped by a promotion, then it
2923 	 * contains valid mappings.  Zero it to invalidate those mappings.
2924 	 */
2925 	if (vm_page_any_valid(mpte))
2926 		pagezero((void *)&KPTmap[i386_btop(trunc_4mpage(va))]);
2927 
2928 	/*
2929 	 * Remove the mapping.
2930 	 */
2931 	if (workaround_erratum383)
2932 		pmap_update_pde(pmap, va, pde, newpde);
2933 	else
2934 		pmap_kenter_pde(va, newpde);
2935 
2936 	/*
2937 	 * Invalidate the recursive mapping of the page table page.
2938 	 */
2939 	pmap_invalidate_page_int(pmap, (vm_offset_t)vtopte(va));
2940 }
2941 
2942 /*
2943  * pmap_remove_pde: do the things to unmap a superpage in a process
2944  */
2945 static void
pmap_remove_pde(pmap_t pmap,pd_entry_t * pdq,vm_offset_t sva,struct spglist * free)2946 pmap_remove_pde(pmap_t pmap, pd_entry_t *pdq, vm_offset_t sva,
2947     struct spglist *free)
2948 {
2949 	struct md_page *pvh;
2950 	pd_entry_t oldpde;
2951 	vm_offset_t eva, va;
2952 	vm_page_t m, mpte;
2953 
2954 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
2955 	KASSERT((sva & PDRMASK) == 0,
2956 	    ("pmap_remove_pde: sva is not 4mpage aligned"));
2957 	oldpde = pte_load_clear(pdq);
2958 	if (oldpde & PG_W)
2959 		pmap->pm_stats.wired_count -= NBPDR / PAGE_SIZE;
2960 
2961 	/*
2962 	 * Machines that don't support invlpg, also don't support
2963 	 * PG_G.
2964 	 */
2965 	if ((oldpde & PG_G) != 0)
2966 		pmap_invalidate_pde_page(kernel_pmap, sva, oldpde);
2967 
2968 	pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE;
2969 	if (oldpde & PG_MANAGED) {
2970 		pvh = pa_to_pvh(oldpde & PG_PS_FRAME);
2971 		pmap_pvh_free(pvh, pmap, sva);
2972 		eva = sva + NBPDR;
2973 		for (va = sva, m = PHYS_TO_VM_PAGE(oldpde & PG_PS_FRAME);
2974 		    va < eva; va += PAGE_SIZE, m++) {
2975 			if ((oldpde & (PG_M | PG_RW)) == (PG_M | PG_RW))
2976 				vm_page_dirty(m);
2977 			if (oldpde & PG_A)
2978 				vm_page_aflag_set(m, PGA_REFERENCED);
2979 			if (TAILQ_EMPTY(&m->md.pv_list) &&
2980 			    TAILQ_EMPTY(&pvh->pv_list))
2981 				vm_page_aflag_clear(m, PGA_WRITEABLE);
2982 		}
2983 	}
2984 	if (pmap == kernel_pmap) {
2985 		pmap_remove_kernel_pde(pmap, pdq, sva);
2986 	} else {
2987 		mpte = pmap_remove_pt_page(pmap, sva);
2988 		if (mpte != NULL) {
2989 			KASSERT(vm_page_any_valid(mpte),
2990 			    ("pmap_remove_pde: pte page not promoted"));
2991 			pmap->pm_stats.resident_count--;
2992 			KASSERT(mpte->ref_count == NPTEPG,
2993 			    ("pmap_remove_pde: pte page ref count error"));
2994 			mpte->ref_count = 0;
2995 			pmap_add_delayed_free_list(mpte, free, false);
2996 		}
2997 	}
2998 }
2999 
3000 /*
3001  * pmap_remove_pte: do the things to unmap a page in a process
3002  */
3003 static int
pmap_remove_pte(pmap_t pmap,pt_entry_t * ptq,vm_offset_t va,struct spglist * free)3004 pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq, vm_offset_t va,
3005     struct spglist *free)
3006 {
3007 	pt_entry_t oldpte;
3008 	vm_page_t m;
3009 
3010 	rw_assert(&pvh_global_lock, RA_WLOCKED);
3011 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
3012 	oldpte = pte_load_clear(ptq);
3013 	KASSERT(oldpte != 0,
3014 	    ("pmap_remove_pte: pmap %p va %x zero pte", pmap, va));
3015 	if (oldpte & PG_W)
3016 		pmap->pm_stats.wired_count -= 1;
3017 	/*
3018 	 * Machines that don't support invlpg, also don't support
3019 	 * PG_G.
3020 	 */
3021 	if (oldpte & PG_G)
3022 		pmap_invalidate_page_int(kernel_pmap, va);
3023 	pmap->pm_stats.resident_count -= 1;
3024 	if (oldpte & PG_MANAGED) {
3025 		m = PHYS_TO_VM_PAGE(oldpte & PG_FRAME);
3026 		if ((oldpte & (PG_M | PG_RW)) == (PG_M | PG_RW))
3027 			vm_page_dirty(m);
3028 		if (oldpte & PG_A)
3029 			vm_page_aflag_set(m, PGA_REFERENCED);
3030 		pmap_remove_entry(pmap, m, va);
3031 	}
3032 	return (pmap_unuse_pt(pmap, va, free));
3033 }
3034 
3035 /*
3036  * Remove a single page from a process address space
3037  */
3038 static void
pmap_remove_page(pmap_t pmap,vm_offset_t va,struct spglist * free)3039 pmap_remove_page(pmap_t pmap, vm_offset_t va, struct spglist *free)
3040 {
3041 	pt_entry_t *pte;
3042 
3043 	rw_assert(&pvh_global_lock, RA_WLOCKED);
3044 	KASSERT(curthread->td_pinned > 0, ("curthread not pinned"));
3045 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
3046 	if ((pte = pmap_pte_quick(pmap, va)) == NULL || *pte == 0)
3047 		return;
3048 	pmap_remove_pte(pmap, pte, va, free);
3049 	pmap_invalidate_page_int(pmap, va);
3050 }
3051 
3052 /*
3053  * Removes the specified range of addresses from the page table page.
3054  */
3055 static bool
pmap_remove_ptes(pmap_t pmap,vm_offset_t sva,vm_offset_t eva,struct spglist * free)3056 pmap_remove_ptes(pmap_t pmap, vm_offset_t sva, vm_offset_t eva,
3057     struct spglist *free)
3058 {
3059 	pt_entry_t *pte;
3060 	bool anyvalid;
3061 
3062 	rw_assert(&pvh_global_lock, RA_WLOCKED);
3063 	KASSERT(curthread->td_pinned > 0, ("curthread not pinned"));
3064 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
3065 	anyvalid = false;
3066 	for (pte = pmap_pte_quick(pmap, sva); sva != eva; pte++,
3067 	    sva += PAGE_SIZE) {
3068 		if (*pte == 0)
3069 			continue;
3070 
3071 		/*
3072 		 * The TLB entry for a PG_G mapping is invalidated by
3073 		 * pmap_remove_pte().
3074 		 */
3075 		if ((*pte & PG_G) == 0)
3076 			anyvalid = true;
3077 
3078 		if (pmap_remove_pte(pmap, pte, sva, free))
3079 			break;
3080 	}
3081 	return (anyvalid);
3082 }
3083 
3084 /*
3085  *	Remove the given range of addresses from the specified map.
3086  *
3087  *	It is assumed that the start and end are properly
3088  *	rounded to the page size.
3089  */
3090 static void
__CONCAT(PMTYPE,remove)3091 __CONCAT(PMTYPE, remove)(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
3092 {
3093 	vm_offset_t pdnxt;
3094 	pd_entry_t ptpaddr;
3095 	struct spglist free;
3096 	int anyvalid;
3097 
3098 	/*
3099 	 * Perform an unsynchronized read.  This is, however, safe.
3100 	 */
3101 	if (pmap->pm_stats.resident_count == 0)
3102 		return;
3103 
3104 	anyvalid = 0;
3105 	SLIST_INIT(&free);
3106 
3107 	rw_wlock(&pvh_global_lock);
3108 	sched_pin();
3109 	PMAP_LOCK(pmap);
3110 
3111 	/*
3112 	 * special handling of removing one page.  a very
3113 	 * common operation and easy to short circuit some
3114 	 * code.
3115 	 */
3116 	if ((sva + PAGE_SIZE == eva) &&
3117 	    ((pmap->pm_pdir[(sva >> PDRSHIFT)] & PG_PS) == 0)) {
3118 		pmap_remove_page(pmap, sva, &free);
3119 		goto out;
3120 	}
3121 
3122 	for (; sva < eva; sva = pdnxt) {
3123 		u_int pdirindex;
3124 
3125 		/*
3126 		 * Calculate index for next page table.
3127 		 */
3128 		pdnxt = (sva + NBPDR) & ~PDRMASK;
3129 		if (pdnxt < sva)
3130 			pdnxt = eva;
3131 		if (pmap->pm_stats.resident_count == 0)
3132 			break;
3133 
3134 		pdirindex = sva >> PDRSHIFT;
3135 		ptpaddr = pmap->pm_pdir[pdirindex];
3136 
3137 		/*
3138 		 * Weed out invalid mappings. Note: we assume that the page
3139 		 * directory table is always allocated, and in kernel virtual.
3140 		 */
3141 		if (ptpaddr == 0)
3142 			continue;
3143 
3144 		/*
3145 		 * Check for large page.
3146 		 */
3147 		if ((ptpaddr & PG_PS) != 0) {
3148 			/*
3149 			 * Are we removing the entire large page?  If not,
3150 			 * demote the mapping and fall through.
3151 			 */
3152 			if (sva + NBPDR == pdnxt && eva >= pdnxt) {
3153 				/*
3154 				 * The TLB entry for a PG_G mapping is
3155 				 * invalidated by pmap_remove_pde().
3156 				 */
3157 				if ((ptpaddr & PG_G) == 0)
3158 					anyvalid = 1;
3159 				pmap_remove_pde(pmap,
3160 				    &pmap->pm_pdir[pdirindex], sva, &free);
3161 				continue;
3162 			} else if (!pmap_demote_pde(pmap,
3163 			    &pmap->pm_pdir[pdirindex], sva)) {
3164 				/* The large page mapping was destroyed. */
3165 				continue;
3166 			}
3167 		}
3168 
3169 		/*
3170 		 * Limit our scan to either the end of the va represented
3171 		 * by the current page table page, or to the end of the
3172 		 * range being removed.
3173 		 */
3174 		if (pdnxt > eva)
3175 			pdnxt = eva;
3176 
3177 		if (pmap_remove_ptes(pmap, sva, pdnxt, &free))
3178 			anyvalid = 1;
3179 	}
3180 out:
3181 	sched_unpin();
3182 	if (anyvalid)
3183 		pmap_invalidate_all_int(pmap);
3184 	rw_wunlock(&pvh_global_lock);
3185 	PMAP_UNLOCK(pmap);
3186 	vm_page_free_pages_toq(&free, true);
3187 }
3188 
3189 /*
3190  *	Routine:	pmap_remove_all
3191  *	Function:
3192  *		Removes this physical page from
3193  *		all physical maps in which it resides.
3194  *		Reflects back modify bits to the pager.
3195  *
3196  *	Notes:
3197  *		Original versions of this routine were very
3198  *		inefficient because they iteratively called
3199  *		pmap_remove (slow...)
3200  */
3201 
3202 static void
__CONCAT(PMTYPE,remove_all)3203 __CONCAT(PMTYPE, remove_all)(vm_page_t m)
3204 {
3205 	struct md_page *pvh;
3206 	pv_entry_t pv;
3207 	pmap_t pmap;
3208 	pt_entry_t *pte, tpte;
3209 	pd_entry_t *pde;
3210 	vm_offset_t va;
3211 	struct spglist free;
3212 
3213 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
3214 	    ("pmap_remove_all: page %p is not managed", m));
3215 	SLIST_INIT(&free);
3216 	rw_wlock(&pvh_global_lock);
3217 	sched_pin();
3218 	if ((m->flags & PG_FICTITIOUS) != 0)
3219 		goto small_mappings;
3220 	pvh = pa_to_pvh(VM_PAGE_TO_PHYS(m));
3221 	while ((pv = TAILQ_FIRST(&pvh->pv_list)) != NULL) {
3222 		va = pv->pv_va;
3223 		pmap = PV_PMAP(pv);
3224 		PMAP_LOCK(pmap);
3225 		pde = pmap_pde(pmap, va);
3226 		(void)pmap_demote_pde(pmap, pde, va);
3227 		PMAP_UNLOCK(pmap);
3228 	}
3229 small_mappings:
3230 	while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) {
3231 		pmap = PV_PMAP(pv);
3232 		PMAP_LOCK(pmap);
3233 		pmap->pm_stats.resident_count--;
3234 		pde = pmap_pde(pmap, pv->pv_va);
3235 		KASSERT((*pde & PG_PS) == 0, ("pmap_remove_all: found"
3236 		    " a 4mpage in page %p's pv list", m));
3237 		pte = pmap_pte_quick(pmap, pv->pv_va);
3238 		tpte = pte_load_clear(pte);
3239 		KASSERT(tpte != 0, ("pmap_remove_all: pmap %p va %x zero pte",
3240 		    pmap, pv->pv_va));
3241 		if (tpte & PG_W)
3242 			pmap->pm_stats.wired_count--;
3243 		if (tpte & PG_A)
3244 			vm_page_aflag_set(m, PGA_REFERENCED);
3245 
3246 		/*
3247 		 * Update the vm_page_t clean and reference bits.
3248 		 */
3249 		if ((tpte & (PG_M | PG_RW)) == (PG_M | PG_RW))
3250 			vm_page_dirty(m);
3251 		pmap_unuse_pt(pmap, pv->pv_va, &free);
3252 		pmap_invalidate_page_int(pmap, pv->pv_va);
3253 		TAILQ_REMOVE(&m->md.pv_list, pv, pv_next);
3254 		free_pv_entry(pmap, pv);
3255 		PMAP_UNLOCK(pmap);
3256 	}
3257 	vm_page_aflag_clear(m, PGA_WRITEABLE);
3258 	sched_unpin();
3259 	rw_wunlock(&pvh_global_lock);
3260 	vm_page_free_pages_toq(&free, true);
3261 }
3262 
3263 /*
3264  * pmap_protect_pde: do the things to protect a 4mpage in a process
3265  */
3266 static bool
pmap_protect_pde(pmap_t pmap,pd_entry_t * pde,vm_offset_t sva,vm_prot_t prot)3267 pmap_protect_pde(pmap_t pmap, pd_entry_t *pde, vm_offset_t sva, vm_prot_t prot)
3268 {
3269 	pd_entry_t newpde, oldpde;
3270 	vm_page_t m, mt;
3271 	bool anychanged;
3272 
3273 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
3274 	KASSERT((sva & PDRMASK) == 0,
3275 	    ("pmap_protect_pde: sva is not 4mpage aligned"));
3276 	anychanged = false;
3277 retry:
3278 	oldpde = newpde = *pde;
3279 	if ((prot & VM_PROT_WRITE) == 0) {
3280 		if ((oldpde & (PG_MANAGED | PG_M | PG_RW)) ==
3281 		    (PG_MANAGED | PG_M | PG_RW)) {
3282 			m = PHYS_TO_VM_PAGE(oldpde & PG_PS_FRAME);
3283 			for (mt = m; mt < &m[NBPDR / PAGE_SIZE]; mt++)
3284 				vm_page_dirty(mt);
3285 		}
3286 		newpde &= ~(PG_RW | PG_M);
3287 	}
3288 #ifdef PMAP_PAE_COMP
3289 	if ((prot & VM_PROT_EXECUTE) == 0 && !i386_read_exec)
3290 		newpde |= pg_nx;
3291 #endif
3292 	if (newpde != oldpde) {
3293 		/*
3294 		 * As an optimization to future operations on this PDE, clear
3295 		 * PG_PROMOTED.  The impending invalidation will remove any
3296 		 * lingering 4KB page mappings from the TLB.
3297 		 */
3298 		if (!pde_cmpset(pde, oldpde, newpde & ~PG_PROMOTED))
3299 			goto retry;
3300 		if ((oldpde & PG_G) != 0)
3301 			pmap_invalidate_pde_page(kernel_pmap, sva, oldpde);
3302 		else
3303 			anychanged = true;
3304 	}
3305 	return (anychanged);
3306 }
3307 
3308 /*
3309  *	Set the physical protection on the
3310  *	specified range of this map as requested.
3311  */
3312 static void
__CONCAT(PMTYPE,protect)3313 __CONCAT(PMTYPE, protect)(pmap_t pmap, vm_offset_t sva, vm_offset_t eva,
3314     vm_prot_t prot)
3315 {
3316 	vm_offset_t pdnxt;
3317 	pd_entry_t ptpaddr;
3318 	pt_entry_t *pte;
3319 	bool anychanged, pv_lists_locked;
3320 
3321 	KASSERT((prot & ~VM_PROT_ALL) == 0, ("invalid prot %x", prot));
3322 	if (prot == VM_PROT_NONE) {
3323 		pmap_remove(pmap, sva, eva);
3324 		return;
3325 	}
3326 
3327 #ifdef PMAP_PAE_COMP
3328 	if ((prot & (VM_PROT_WRITE | VM_PROT_EXECUTE)) ==
3329 	    (VM_PROT_WRITE | VM_PROT_EXECUTE))
3330 		return;
3331 #else
3332 	if (prot & VM_PROT_WRITE)
3333 		return;
3334 #endif
3335 
3336 	if (pmap_is_current(pmap))
3337 		pv_lists_locked = false;
3338 	else {
3339 		pv_lists_locked = true;
3340 resume:
3341 		rw_wlock(&pvh_global_lock);
3342 		sched_pin();
3343 	}
3344 	anychanged = false;
3345 
3346 	PMAP_LOCK(pmap);
3347 	for (; sva < eva; sva = pdnxt) {
3348 		pt_entry_t obits, pbits;
3349 		u_int pdirindex;
3350 
3351 		pdnxt = (sva + NBPDR) & ~PDRMASK;
3352 		if (pdnxt < sva)
3353 			pdnxt = eva;
3354 
3355 		pdirindex = sva >> PDRSHIFT;
3356 		ptpaddr = pmap->pm_pdir[pdirindex];
3357 
3358 		/*
3359 		 * Weed out invalid mappings. Note: we assume that the page
3360 		 * directory table is always allocated, and in kernel virtual.
3361 		 */
3362 		if (ptpaddr == 0)
3363 			continue;
3364 
3365 		/*
3366 		 * Check for large page.
3367 		 */
3368 		if ((ptpaddr & PG_PS) != 0) {
3369 			/*
3370 			 * Are we protecting the entire large page?  If not,
3371 			 * demote the mapping and fall through.
3372 			 */
3373 			if (sva + NBPDR == pdnxt && eva >= pdnxt) {
3374 				/*
3375 				 * The TLB entry for a PG_G mapping is
3376 				 * invalidated by pmap_protect_pde().
3377 				 */
3378 				if (pmap_protect_pde(pmap,
3379 				    &pmap->pm_pdir[pdirindex], sva, prot))
3380 					anychanged = true;
3381 				continue;
3382 			} else {
3383 				if (!pv_lists_locked) {
3384 					pv_lists_locked = true;
3385 					if (!rw_try_wlock(&pvh_global_lock)) {
3386 						if (anychanged)
3387 							pmap_invalidate_all_int(
3388 							    pmap);
3389 						PMAP_UNLOCK(pmap);
3390 						goto resume;
3391 					}
3392 					sched_pin();
3393 				}
3394 				if (!pmap_demote_pde(pmap,
3395 				    &pmap->pm_pdir[pdirindex], sva)) {
3396 					/*
3397 					 * The large page mapping was
3398 					 * destroyed.
3399 					 */
3400 					continue;
3401 				}
3402 			}
3403 		}
3404 
3405 		if (pdnxt > eva)
3406 			pdnxt = eva;
3407 
3408 		for (pte = pmap_pte_quick(pmap, sva); sva != pdnxt; pte++,
3409 		    sva += PAGE_SIZE) {
3410 			vm_page_t m;
3411 
3412 retry:
3413 			/*
3414 			 * Regardless of whether a pte is 32 or 64 bits in
3415 			 * size, PG_RW, PG_A, and PG_M are among the least
3416 			 * significant 32 bits.
3417 			 */
3418 			obits = pbits = *pte;
3419 			if ((pbits & PG_V) == 0)
3420 				continue;
3421 
3422 			if ((prot & VM_PROT_WRITE) == 0) {
3423 				if ((pbits & (PG_MANAGED | PG_M | PG_RW)) ==
3424 				    (PG_MANAGED | PG_M | PG_RW)) {
3425 					m = PHYS_TO_VM_PAGE(pbits & PG_FRAME);
3426 					vm_page_dirty(m);
3427 				}
3428 				pbits &= ~(PG_RW | PG_M);
3429 			}
3430 #ifdef PMAP_PAE_COMP
3431 			if ((prot & VM_PROT_EXECUTE) == 0 && !i386_read_exec)
3432 				pbits |= pg_nx;
3433 #endif
3434 
3435 			if (pbits != obits) {
3436 #ifdef PMAP_PAE_COMP
3437 				if (!atomic_cmpset_64(pte, obits, pbits))
3438 					goto retry;
3439 #else
3440 				if (!atomic_cmpset_int((u_int *)pte, obits,
3441 				    pbits))
3442 					goto retry;
3443 #endif
3444 				if (obits & PG_G)
3445 					pmap_invalidate_page_int(pmap, sva);
3446 				else
3447 					anychanged = true;
3448 			}
3449 		}
3450 	}
3451 	if (anychanged)
3452 		pmap_invalidate_all_int(pmap);
3453 	if (pv_lists_locked) {
3454 		sched_unpin();
3455 		rw_wunlock(&pvh_global_lock);
3456 	}
3457 	PMAP_UNLOCK(pmap);
3458 }
3459 
3460 #if VM_NRESERVLEVEL > 0
3461 /*
3462  * Tries to promote the 512 or 1024, contiguous 4KB page mappings that are
3463  * within a single page table page (PTP) to a single 2- or 4MB page mapping.
3464  * For promotion to occur, two conditions must be met: (1) the 4KB page
3465  * mappings must map aligned, contiguous physical memory and (2) the 4KB page
3466  * mappings must have identical characteristics.
3467  *
3468  * Managed (PG_MANAGED) mappings within the kernel address space are not
3469  * promoted.  The reason is that kernel PDEs are replicated in each pmap but
3470  * pmap_clear_ptes() and pmap_ts_referenced() only read the PDE from the kernel
3471  * pmap.
3472  */
3473 static bool
pmap_promote_pde(pmap_t pmap,pd_entry_t * pde,vm_offset_t va,vm_page_t mpte)3474 pmap_promote_pde(pmap_t pmap, pd_entry_t *pde, vm_offset_t va, vm_page_t mpte)
3475 {
3476 	pd_entry_t newpde;
3477 	pt_entry_t allpte_PG_A, *firstpte, oldpte, pa, *pte;
3478 #ifdef KTR
3479 	vm_offset_t oldpteva;
3480 #endif
3481 
3482 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
3483 	if (!pg_ps_enabled)
3484 		return (false);
3485 
3486 	/*
3487 	 * Examine the first PTE in the specified PTP.  Abort if this PTE is
3488 	 * either invalid or does not map the first 4KB physical page
3489 	 * within a 2- or 4MB page.
3490 	 */
3491 	firstpte = pmap_pte_quick(pmap, trunc_4mpage(va));
3492 setpde:
3493 	newpde = *firstpte;
3494 	if ((newpde & ((PG_FRAME & PDRMASK) | PG_V)) != PG_V) {
3495 		pmap_pde_p_failures++;
3496 		CTR2(KTR_PMAP, "pmap_promote_pde: failure for va %#x"
3497 		    " in pmap %p", va, pmap);
3498 		return (false);
3499 	}
3500 	if ((*firstpte & PG_MANAGED) != 0 && pmap == kernel_pmap) {
3501 		pmap_pde_p_failures++;
3502 		CTR2(KTR_PMAP, "pmap_promote_pde: failure for va %#x"
3503 		    " in pmap %p", va, pmap);
3504 		return (false);
3505 	}
3506 
3507 	/*
3508 	 * Both here and in the below "for" loop, to allow for repromotion
3509 	 * after MADV_FREE, conditionally write protect a clean PTE before
3510 	 * possibly aborting the promotion due to other PTE attributes.  Why?
3511 	 * Suppose that MADV_FREE is applied to a part of a superpage, the
3512 	 * address range [S, E).  pmap_advise() will demote the superpage
3513 	 * mapping, destroy the 4KB page mapping at the end of [S, E), and
3514 	 * clear PG_M and PG_A in the PTEs for the rest of [S, E).  Later,
3515 	 * imagine that the memory in [S, E) is recycled, but the last 4KB
3516 	 * page in [S, E) is not the last to be rewritten, or simply accessed.
3517 	 * In other words, there is still a 4KB page in [S, E), call it P,
3518 	 * that is writeable but PG_M and PG_A are clear in P's PTE.  Unless
3519 	 * we write protect P before aborting the promotion, if and when P is
3520 	 * finally rewritten, there won't be a page fault to trigger
3521 	 * repromotion.
3522 	 */
3523 	if ((newpde & (PG_M | PG_RW)) == PG_RW) {
3524 		/*
3525 		 * When PG_M is already clear, PG_RW can be cleared without
3526 		 * a TLB invalidation.
3527 		 */
3528 		if (!atomic_cmpset_int((u_int *)firstpte, newpde, newpde &
3529 		    ~PG_RW))
3530 			goto setpde;
3531 		newpde &= ~PG_RW;
3532 		CTR2(KTR_PMAP, "pmap_promote_pde: protect for va %#lx"
3533 		    " in pmap %p", va & ~PDRMASK, pmap);
3534 	}
3535 
3536 	/*
3537 	 * Examine each of the other PTEs in the specified PTP.  Abort if this
3538 	 * PTE maps an unexpected 4KB physical page or does not have identical
3539 	 * characteristics to the first PTE.
3540 	 */
3541 	allpte_PG_A = newpde & PG_A;
3542 	pa = (newpde & (PG_PS_FRAME | PG_V)) + NBPDR - PAGE_SIZE;
3543 	for (pte = firstpte + NPTEPG - 1; pte > firstpte; pte--) {
3544 setpte:
3545 		oldpte = *pte;
3546 		if ((oldpte & (PG_FRAME | PG_V)) != pa) {
3547 			pmap_pde_p_failures++;
3548 			CTR2(KTR_PMAP, "pmap_promote_pde: failure for va %#x"
3549 			    " in pmap %p", va, pmap);
3550 			return (false);
3551 		}
3552 		if ((oldpte & (PG_M | PG_RW)) == PG_RW) {
3553 			/*
3554 			 * When PG_M is already clear, PG_RW can be cleared
3555 			 * without a TLB invalidation.
3556 			 */
3557 			if (!atomic_cmpset_int((u_int *)pte, oldpte,
3558 			    oldpte & ~PG_RW))
3559 				goto setpte;
3560 			oldpte &= ~PG_RW;
3561 #ifdef KTR
3562 			oldpteva = (oldpte & PG_FRAME & PDRMASK) |
3563 			    (va & ~PDRMASK);
3564 #endif
3565 			CTR2(KTR_PMAP, "pmap_promote_pde: protect for va %#x"
3566 			    " in pmap %p", oldpteva, pmap);
3567 		}
3568 		if ((oldpte & PG_PTE_PROMOTE) != (newpde & PG_PTE_PROMOTE)) {
3569 			pmap_pde_p_failures++;
3570 			CTR2(KTR_PMAP, "pmap_promote_pde: failure for va %#x"
3571 			    " in pmap %p", va, pmap);
3572 			return (false);
3573 		}
3574 		allpte_PG_A &= oldpte;
3575 		pa -= PAGE_SIZE;
3576 	}
3577 
3578 	/*
3579 	 * Unless all PTEs have PG_A set, clear it from the superpage mapping,
3580 	 * so that promotions triggered by speculative mappings, such as
3581 	 * pmap_enter_quick(), don't automatically mark the underlying pages
3582 	 * as referenced.
3583 	 */
3584 	newpde &= ~PG_A | allpte_PG_A;
3585 
3586 	/*
3587 	 * Save the PTP in its current state until the PDE mapping the
3588 	 * superpage is demoted by pmap_demote_pde() or destroyed by
3589 	 * pmap_remove_pde().  If PG_A is not set in every PTE, then request
3590 	 * that the PTP be refilled on demotion.
3591 	 */
3592 	if (mpte == NULL)
3593 		mpte = PHYS_TO_VM_PAGE(*pde & PG_FRAME);
3594 	KASSERT(mpte >= vm_page_array &&
3595 	    mpte < &vm_page_array[vm_page_array_size],
3596 	    ("pmap_promote_pde: page table page is out of range"));
3597 	KASSERT(mpte->pindex == va >> PDRSHIFT,
3598 	    ("pmap_promote_pde: page table page's pindex is wrong"));
3599 	if (pmap_insert_pt_page(pmap, mpte, true, allpte_PG_A != 0)) {
3600 		pmap_pde_p_failures++;
3601 		CTR2(KTR_PMAP,
3602 		    "pmap_promote_pde: failure for va %#x in pmap %p", va,
3603 		    pmap);
3604 		return (false);
3605 	}
3606 
3607 	/*
3608 	 * Promote the pv entries.
3609 	 */
3610 	if ((newpde & PG_MANAGED) != 0)
3611 		pmap_pv_promote_pde(pmap, va, newpde & PG_PS_FRAME);
3612 
3613 	/*
3614 	 * Propagate the PAT index to its proper position.
3615 	 */
3616 	if ((newpde & PG_PTE_PAT) != 0)
3617 		newpde ^= PG_PDE_PAT | PG_PTE_PAT;
3618 
3619 	/*
3620 	 * Map the superpage.
3621 	 */
3622 	if (workaround_erratum383)
3623 		pmap_update_pde(pmap, va, pde, PG_PS | newpde);
3624 	else if (pmap == kernel_pmap)
3625 		pmap_kenter_pde(va, PG_PROMOTED | PG_PS | newpde);
3626 	else
3627 		pde_store(pde, PG_PROMOTED | PG_PS | newpde);
3628 
3629 	pmap_pde_promotions++;
3630 	CTR2(KTR_PMAP, "pmap_promote_pde: success for va %#x"
3631 	    " in pmap %p", va, pmap);
3632 	return (true);
3633 }
3634 #endif /* VM_NRESERVLEVEL > 0 */
3635 
3636 /*
3637  *	Insert the given physical page (p) at
3638  *	the specified virtual address (v) in the
3639  *	target physical map with the protection requested.
3640  *
3641  *	If specified, the page will be wired down, meaning
3642  *	that the related pte can not be reclaimed.
3643  *
3644  *	NB:  This is the only routine which MAY NOT lazy-evaluate
3645  *	or lose information.  That is, this routine must actually
3646  *	insert this page into the given map NOW.
3647  */
3648 static int
__CONCAT(PMTYPE,enter)3649 __CONCAT(PMTYPE, enter)(pmap_t pmap, vm_offset_t va, vm_page_t m,
3650     vm_prot_t prot, u_int flags, int8_t psind)
3651 {
3652 	pd_entry_t *pde;
3653 	pt_entry_t *pte;
3654 	pt_entry_t newpte, origpte;
3655 	pv_entry_t pv;
3656 	vm_paddr_t opa, pa;
3657 	vm_page_t mpte, om;
3658 	int rv;
3659 
3660 	va = trunc_page(va);
3661 	KASSERT((pmap == kernel_pmap && va < VM_MAX_KERNEL_ADDRESS) ||
3662 	    (pmap != kernel_pmap && va < VM_MAXUSER_ADDRESS),
3663 	    ("pmap_enter: toobig k%d %#x", pmap == kernel_pmap, va));
3664 	KASSERT(va < PMAP_TRM_MIN_ADDRESS,
3665 	    ("pmap_enter: invalid to pmap_enter into trampoline (va: 0x%x)",
3666 	    va));
3667 	KASSERT(pmap != kernel_pmap || (m->oflags & VPO_UNMANAGED) != 0 ||
3668 	    !VA_IS_CLEANMAP(va),
3669 	    ("pmap_enter: managed mapping within the clean submap"));
3670 	if ((m->oflags & VPO_UNMANAGED) == 0)
3671 		VM_PAGE_OBJECT_BUSY_ASSERT(m);
3672 	KASSERT((flags & PMAP_ENTER_RESERVED) == 0,
3673 	    ("pmap_enter: flags %u has reserved bits set", flags));
3674 	pa = VM_PAGE_TO_PHYS(m);
3675 	newpte = (pt_entry_t)(pa | PG_A | PG_V);
3676 	if ((flags & VM_PROT_WRITE) != 0)
3677 		newpte |= PG_M;
3678 	if ((prot & VM_PROT_WRITE) != 0)
3679 		newpte |= PG_RW;
3680 	KASSERT((newpte & (PG_M | PG_RW)) != PG_M,
3681 	    ("pmap_enter: flags includes VM_PROT_WRITE but prot doesn't"));
3682 #ifdef PMAP_PAE_COMP
3683 	if ((prot & VM_PROT_EXECUTE) == 0 && !i386_read_exec)
3684 		newpte |= pg_nx;
3685 #endif
3686 	if ((flags & PMAP_ENTER_WIRED) != 0)
3687 		newpte |= PG_W;
3688 	if (pmap != kernel_pmap)
3689 		newpte |= PG_U;
3690 	newpte |= pmap_cache_bits(pmap, m->md.pat_mode, psind > 0);
3691 	if ((m->oflags & VPO_UNMANAGED) == 0)
3692 		newpte |= PG_MANAGED;
3693 
3694 	rw_wlock(&pvh_global_lock);
3695 	PMAP_LOCK(pmap);
3696 	sched_pin();
3697 	if (psind == 1) {
3698 		/* Assert the required virtual and physical alignment. */
3699 		KASSERT((va & PDRMASK) == 0, ("pmap_enter: va unaligned"));
3700 		KASSERT(m->psind > 0, ("pmap_enter: m->psind < psind"));
3701 		rv = pmap_enter_pde(pmap, va, newpte | PG_PS, flags, m);
3702 		goto out;
3703 	}
3704 
3705 	pde = pmap_pde(pmap, va);
3706 	if (pmap != kernel_pmap) {
3707 		/*
3708 		 * va is for UVA.
3709 		 * In the case that a page table page is not resident,
3710 		 * we are creating it here.  pmap_allocpte() handles
3711 		 * demotion.
3712 		 */
3713 		mpte = pmap_allocpte(pmap, va, flags);
3714 		if (mpte == NULL) {
3715 			KASSERT((flags & PMAP_ENTER_NOSLEEP) != 0,
3716 			    ("pmap_allocpte failed with sleep allowed"));
3717 			rv = KERN_RESOURCE_SHORTAGE;
3718 			goto out;
3719 		}
3720 	} else {
3721 		/*
3722 		 * va is for KVA, so pmap_demote_pde() will never fail
3723 		 * to install a page table page.  PG_V is also
3724 		 * asserted by pmap_demote_pde().
3725 		 */
3726 		mpte = NULL;
3727 		KASSERT(pde != NULL && (*pde & PG_V) != 0,
3728 		    ("KVA %#x invalid pde pdir %#jx", va,
3729 		    (uintmax_t)pmap->pm_pdir[PTDPTDI]));
3730 		if ((*pde & PG_PS) != 0)
3731 			pmap_demote_pde(pmap, pde, va);
3732 	}
3733 	pte = pmap_pte_quick(pmap, va);
3734 
3735 	/*
3736 	 * Page Directory table entry is not valid, which should not
3737 	 * happen.  We should have either allocated the page table
3738 	 * page or demoted the existing mapping above.
3739 	 */
3740 	if (pte == NULL) {
3741 		panic("pmap_enter: invalid page directory pdir=%#jx, va=%#x",
3742 		    (uintmax_t)pmap->pm_pdir[PTDPTDI], va);
3743 	}
3744 
3745 	origpte = *pte;
3746 	pv = NULL;
3747 
3748 	/*
3749 	 * Is the specified virtual address already mapped?
3750 	 */
3751 	if ((origpte & PG_V) != 0) {
3752 		/*
3753 		 * Wiring change, just update stats. We don't worry about
3754 		 * wiring PT pages as they remain resident as long as there
3755 		 * are valid mappings in them. Hence, if a user page is wired,
3756 		 * the PT page will be also.
3757 		 */
3758 		if ((newpte & PG_W) != 0 && (origpte & PG_W) == 0)
3759 			pmap->pm_stats.wired_count++;
3760 		else if ((newpte & PG_W) == 0 && (origpte & PG_W) != 0)
3761 			pmap->pm_stats.wired_count--;
3762 
3763 		/*
3764 		 * Remove the extra PT page reference.
3765 		 */
3766 		if (mpte != NULL) {
3767 			mpte->ref_count--;
3768 			KASSERT(mpte->ref_count > 0,
3769 			    ("pmap_enter: missing reference to page table page,"
3770 			     " va: 0x%x", va));
3771 		}
3772 
3773 		/*
3774 		 * Has the physical page changed?
3775 		 */
3776 		opa = origpte & PG_FRAME;
3777 		if (opa == pa) {
3778 			/*
3779 			 * No, might be a protection or wiring change.
3780 			 */
3781 			if ((origpte & PG_MANAGED) != 0 &&
3782 			    (newpte & PG_RW) != 0)
3783 				vm_page_aflag_set(m, PGA_WRITEABLE);
3784 			if (((origpte ^ newpte) & ~(PG_M | PG_A)) == 0)
3785 				goto unchanged;
3786 			goto validate;
3787 		}
3788 
3789 		/*
3790 		 * The physical page has changed.  Temporarily invalidate
3791 		 * the mapping.  This ensures that all threads sharing the
3792 		 * pmap keep a consistent view of the mapping, which is
3793 		 * necessary for the correct handling of COW faults.  It
3794 		 * also permits reuse of the old mapping's PV entry,
3795 		 * avoiding an allocation.
3796 		 *
3797 		 * For consistency, handle unmanaged mappings the same way.
3798 		 */
3799 		origpte = pte_load_clear(pte);
3800 		KASSERT((origpte & PG_FRAME) == opa,
3801 		    ("pmap_enter: unexpected pa update for %#x", va));
3802 		if ((origpte & PG_MANAGED) != 0) {
3803 			om = PHYS_TO_VM_PAGE(opa);
3804 
3805 			/*
3806 			 * The pmap lock is sufficient to synchronize with
3807 			 * concurrent calls to pmap_page_test_mappings() and
3808 			 * pmap_ts_referenced().
3809 			 */
3810 			if ((origpte & (PG_M | PG_RW)) == (PG_M | PG_RW))
3811 				vm_page_dirty(om);
3812 			if ((origpte & PG_A) != 0) {
3813 				pmap_invalidate_page_int(pmap, va);
3814 				vm_page_aflag_set(om, PGA_REFERENCED);
3815 			}
3816 			pv = pmap_pvh_remove(&om->md, pmap, va);
3817 			KASSERT(pv != NULL,
3818 			    ("pmap_enter: no PV entry for %#x", va));
3819 			if ((newpte & PG_MANAGED) == 0)
3820 				free_pv_entry(pmap, pv);
3821 			if ((om->a.flags & PGA_WRITEABLE) != 0 &&
3822 			    TAILQ_EMPTY(&om->md.pv_list) &&
3823 			    ((om->flags & PG_FICTITIOUS) != 0 ||
3824 			    TAILQ_EMPTY(&pa_to_pvh(opa)->pv_list)))
3825 				vm_page_aflag_clear(om, PGA_WRITEABLE);
3826 		} else {
3827 			/*
3828 			 * Since this mapping is unmanaged, assume that PG_A
3829 			 * is set.
3830 			 */
3831 			pmap_invalidate_page_int(pmap, va);
3832 		}
3833 		origpte = 0;
3834 	} else {
3835 		/*
3836 		 * Increment the counters.
3837 		 */
3838 		if ((newpte & PG_W) != 0)
3839 			pmap->pm_stats.wired_count++;
3840 		pmap->pm_stats.resident_count++;
3841 	}
3842 
3843 	/*
3844 	 * Enter on the PV list if part of our managed memory.
3845 	 */
3846 	if ((newpte & PG_MANAGED) != 0) {
3847 		if (pv == NULL) {
3848 			pv = get_pv_entry(pmap, false);
3849 			pv->pv_va = va;
3850 		}
3851 		TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_next);
3852 		if ((newpte & PG_RW) != 0)
3853 			vm_page_aflag_set(m, PGA_WRITEABLE);
3854 	}
3855 
3856 	/*
3857 	 * Update the PTE.
3858 	 */
3859 	if ((origpte & PG_V) != 0) {
3860 validate:
3861 		origpte = pte_load_store(pte, newpte);
3862 		KASSERT((origpte & PG_FRAME) == pa,
3863 		    ("pmap_enter: unexpected pa update for %#x", va));
3864 		if ((newpte & PG_M) == 0 && (origpte & (PG_M | PG_RW)) ==
3865 		    (PG_M | PG_RW)) {
3866 			if ((origpte & PG_MANAGED) != 0)
3867 				vm_page_dirty(m);
3868 
3869 			/*
3870 			 * Although the PTE may still have PG_RW set, TLB
3871 			 * invalidation may nonetheless be required because
3872 			 * the PTE no longer has PG_M set.
3873 			 */
3874 		}
3875 #ifdef PMAP_PAE_COMP
3876 		else if ((origpte & PG_NX) != 0 || (newpte & PG_NX) == 0) {
3877 			/*
3878 			 * This PTE change does not require TLB invalidation.
3879 			 */
3880 			goto unchanged;
3881 		}
3882 #endif
3883 		if ((origpte & PG_A) != 0)
3884 			pmap_invalidate_page_int(pmap, va);
3885 	} else
3886 		pte_store_zero(pte, newpte);
3887 
3888 unchanged:
3889 
3890 #if VM_NRESERVLEVEL > 0
3891 	/*
3892 	 * If both the page table page and the reservation are fully
3893 	 * populated, then attempt promotion.
3894 	 */
3895 	if ((mpte == NULL || mpte->ref_count == NPTEPG) &&
3896 	    (m->flags & PG_FICTITIOUS) == 0 &&
3897 	    vm_reserv_level_iffullpop(m) == 0)
3898 		(void)pmap_promote_pde(pmap, pde, va, mpte);
3899 #endif
3900 
3901 	rv = KERN_SUCCESS;
3902 out:
3903 	sched_unpin();
3904 	rw_wunlock(&pvh_global_lock);
3905 	PMAP_UNLOCK(pmap);
3906 	return (rv);
3907 }
3908 
3909 /*
3910  * Tries to create a read- and/or execute-only 2 or 4 MB page mapping.  Returns
3911  * KERN_SUCCESS if the mapping was created.  Otherwise, returns an error
3912  * value.  See pmap_enter_pde() for the possible error values when "no sleep",
3913  * "no replace", and "no reclaim" are specified.
3914  */
3915 static int
pmap_enter_4mpage(pmap_t pmap,vm_offset_t va,vm_page_t m,vm_prot_t prot)3916 pmap_enter_4mpage(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot)
3917 {
3918 	pd_entry_t newpde;
3919 
3920 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
3921 	newpde = VM_PAGE_TO_PHYS(m) |
3922 	    pmap_cache_bits(pmap, m->md.pat_mode, true) | PG_PS | PG_V;
3923 	if ((m->oflags & VPO_UNMANAGED) == 0)
3924 		newpde |= PG_MANAGED;
3925 #ifdef PMAP_PAE_COMP
3926 	if ((prot & VM_PROT_EXECUTE) == 0 && !i386_read_exec)
3927 		newpde |= pg_nx;
3928 #endif
3929 	if (pmap != kernel_pmap)
3930 		newpde |= PG_U;
3931 	return (pmap_enter_pde(pmap, va, newpde, PMAP_ENTER_NOSLEEP |
3932 	    PMAP_ENTER_NOREPLACE | PMAP_ENTER_NORECLAIM, NULL));
3933 }
3934 
3935 /*
3936  * Returns true if every page table entry in the page table page that maps
3937  * the specified kernel virtual address is zero.
3938  */
3939 static bool
pmap_every_pte_zero(vm_offset_t va)3940 pmap_every_pte_zero(vm_offset_t va)
3941 {
3942 	pt_entry_t *pt_end, *pte;
3943 
3944 	KASSERT((va & PDRMASK) == 0, ("va is misaligned"));
3945 	pte = vtopte(va);
3946 	for (pt_end = pte + NPTEPG; pte < pt_end; pte++) {
3947 		if (*pte != 0)
3948 			return (false);
3949 	}
3950 	return (true);
3951 }
3952 
3953 /*
3954  * Tries to create the specified 2 or 4 MB page mapping.  Returns KERN_SUCCESS
3955  * if the mapping was created, and one of KERN_FAILURE, KERN_NO_SPACE,
3956  * or KERN_RESOURCE_SHORTAGE otherwise.  Returns KERN_FAILURE if
3957  * PMAP_ENTER_NOREPLACE was specified and a 4 KB page mapping already exists
3958  * within the 2 or 4 MB virtual address range starting at the specified virtual
3959  * address.  Returns KERN_NO_SPACE if PMAP_ENTER_NOREPLACE was specified and a
3960  * 2 or 4 MB page mapping already exists at the specified virtual address.
3961  * Returns KERN_RESOURCE_SHORTAGE if PMAP_ENTER_NORECLAIM was specified and a
3962  * PV entry allocation failed.
3963  *
3964  * The parameter "m" is only used when creating a managed, writeable mapping.
3965  */
3966 static int
pmap_enter_pde(pmap_t pmap,vm_offset_t va,pd_entry_t newpde,u_int flags,vm_page_t m)3967 pmap_enter_pde(pmap_t pmap, vm_offset_t va, pd_entry_t newpde, u_int flags,
3968     vm_page_t m)
3969 {
3970 	struct spglist free;
3971 	pd_entry_t oldpde, *pde;
3972 	vm_page_t mt;
3973 	vm_page_t uwptpg;
3974 
3975 	rw_assert(&pvh_global_lock, RA_WLOCKED);
3976 	KASSERT((newpde & (PG_M | PG_RW)) != PG_RW,
3977 	    ("pmap_enter_pde: newpde is missing PG_M"));
3978 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
3979 	pde = pmap_pde(pmap, va);
3980 	oldpde = *pde;
3981 	if ((oldpde & PG_V) != 0) {
3982 		if ((flags & PMAP_ENTER_NOREPLACE) != 0) {
3983 			if ((oldpde & PG_PS) != 0) {
3984 				CTR2(KTR_PMAP,
3985 				    "pmap_enter_pde: no space for va %#lx"
3986 				    " in pmap %p", va, pmap);
3987 				return (KERN_NO_SPACE);
3988 			} else if (pmap != kernel_pmap ||
3989 			    !pmap_every_pte_zero(va)) {
3990 				CTR2(KTR_PMAP,
3991 				    "pmap_enter_pde: failure for va %#lx"
3992 				    " in pmap %p", va, pmap);
3993 				return (KERN_FAILURE);
3994 			}
3995 		}
3996 		/* Break the existing mapping(s). */
3997 		SLIST_INIT(&free);
3998 		if ((oldpde & PG_PS) != 0) {
3999 			/*
4000 			 * If the PDE resulted from a promotion, then a
4001 			 * reserved PT page could be freed.
4002 			 */
4003 			(void)pmap_remove_pde(pmap, pde, va, &free);
4004 			if ((oldpde & PG_G) == 0)
4005 				pmap_invalidate_pde_page(pmap, va, oldpde);
4006 		} else {
4007 			if (pmap_remove_ptes(pmap, va, va + NBPDR, &free))
4008 		               pmap_invalidate_all_int(pmap);
4009 		}
4010 		if (pmap != kernel_pmap) {
4011 			vm_page_free_pages_toq(&free, true);
4012 			KASSERT(*pde == 0, ("pmap_enter_pde: non-zero pde %p",
4013 			    pde));
4014 		} else {
4015 			KASSERT(SLIST_EMPTY(&free),
4016 			    ("pmap_enter_pde: freed kernel page table page"));
4017 
4018 			/*
4019 			 * Both pmap_remove_pde() and pmap_remove_ptes() will
4020 			 * leave the kernel page table page zero filled.
4021 			 */
4022 			mt = PHYS_TO_VM_PAGE(*pde & PG_FRAME);
4023 			if (pmap_insert_pt_page(pmap, mt, false, false))
4024 				panic("pmap_enter_pde: trie insert failed");
4025 		}
4026 	}
4027 
4028 	/*
4029 	 * Allocate a leaf ptpage for wired userspace pages.
4030 	 */
4031 	uwptpg = NULL;
4032 	if ((newpde & PG_W) != 0 && pmap != kernel_pmap) {
4033 		uwptpg = vm_page_alloc_noobj(VM_ALLOC_WIRED);
4034 		if (uwptpg == NULL) {
4035 			return (KERN_RESOURCE_SHORTAGE);
4036 		}
4037 		uwptpg->pindex = va >> PDRSHIFT;
4038 		if (pmap_insert_pt_page(pmap, uwptpg, true, false)) {
4039 			vm_page_unwire_noq(uwptpg);
4040 			vm_page_free(uwptpg);
4041 			return (KERN_RESOURCE_SHORTAGE);
4042 		}
4043 		pmap->pm_stats.resident_count++;
4044 		uwptpg->ref_count = NPTEPG;
4045 	}
4046 	if ((newpde & PG_MANAGED) != 0) {
4047 		/*
4048 		 * Abort this mapping if its PV entry could not be created.
4049 		 */
4050 		if (!pmap_pv_insert_pde(pmap, va, newpde, flags)) {
4051 			if (uwptpg != NULL) {
4052 				mt = pmap_remove_pt_page(pmap, va);
4053 				KASSERT(mt == uwptpg,
4054 				    ("removed pt page %p, expected %p", mt,
4055 				    uwptpg));
4056 				pmap->pm_stats.resident_count--;
4057 				uwptpg->ref_count = 1;
4058 				vm_page_unwire_noq(uwptpg);
4059 				vm_page_free(uwptpg);
4060 			}
4061 			CTR2(KTR_PMAP, "pmap_enter_pde: failure for va %#lx"
4062 			    " in pmap %p", va, pmap);
4063 			return (KERN_RESOURCE_SHORTAGE);
4064 		}
4065 		if ((newpde & PG_RW) != 0) {
4066 			for (mt = m; mt < &m[NBPDR / PAGE_SIZE]; mt++)
4067 				vm_page_aflag_set(mt, PGA_WRITEABLE);
4068 		}
4069 	}
4070 
4071 	/*
4072 	 * Increment counters.
4073 	 */
4074 	if ((newpde & PG_W) != 0)
4075 		pmap->pm_stats.wired_count += NBPDR / PAGE_SIZE;
4076 	pmap->pm_stats.resident_count += NBPDR / PAGE_SIZE;
4077 
4078 	/*
4079 	 * Map the superpage.  (This is not a promoted mapping; there will not
4080 	 * be any lingering 4KB page mappings in the TLB.)
4081 	 */
4082 	pde_store(pde, newpde);
4083 
4084 	pmap_pde_mappings++;
4085 	CTR2(KTR_PMAP, "pmap_enter_pde: success for va %#lx in pmap %p",
4086 	    va, pmap);
4087 	return (KERN_SUCCESS);
4088 }
4089 
4090 /*
4091  * Maps a sequence of resident pages belonging to the same object.
4092  * The sequence begins with the given page m_start.  This page is
4093  * mapped at the given virtual address start.  Each subsequent page is
4094  * mapped at a virtual address that is offset from start by the same
4095  * amount as the page is offset from m_start within the object.  The
4096  * last page in the sequence is the page with the largest offset from
4097  * m_start that can be mapped at a virtual address less than the given
4098  * virtual address end.  Not every virtual page between start and end
4099  * is mapped; only those for which a resident page exists with the
4100  * corresponding offset from m_start are mapped.
4101  */
4102 static void
__CONCAT(PMTYPE,enter_object)4103 __CONCAT(PMTYPE, enter_object)(pmap_t pmap, vm_offset_t start, vm_offset_t end,
4104     vm_page_t m_start, vm_prot_t prot)
4105 {
4106 	vm_offset_t va;
4107 	vm_page_t m, mpte;
4108 	vm_pindex_t diff, psize;
4109 	int rv;
4110 
4111 	VM_OBJECT_ASSERT_LOCKED(m_start->object);
4112 
4113 	psize = atop(end - start);
4114 	mpte = NULL;
4115 	m = m_start;
4116 	rw_wlock(&pvh_global_lock);
4117 	PMAP_LOCK(pmap);
4118 	while (m != NULL && (diff = m->pindex - m_start->pindex) < psize) {
4119 		va = start + ptoa(diff);
4120 		if ((va & PDRMASK) == 0 && va + NBPDR <= end &&
4121 		    m->psind == 1 && pg_ps_enabled &&
4122 		    ((rv = pmap_enter_4mpage(pmap, va, m, prot)) ==
4123 		    KERN_SUCCESS || rv == KERN_NO_SPACE))
4124 			m = &m[NBPDR / PAGE_SIZE - 1];
4125 		else
4126 			mpte = pmap_enter_quick_locked(pmap, va, m, prot,
4127 			    mpte);
4128 		m = TAILQ_NEXT(m, listq);
4129 	}
4130 	rw_wunlock(&pvh_global_lock);
4131 	PMAP_UNLOCK(pmap);
4132 }
4133 
4134 /*
4135  * this code makes some *MAJOR* assumptions:
4136  * 1. Current pmap & pmap exists.
4137  * 2. Not wired.
4138  * 3. Read access.
4139  * 4. No page table pages.
4140  * but is *MUCH* faster than pmap_enter...
4141  */
4142 
4143 static void
__CONCAT(PMTYPE,enter_quick)4144 __CONCAT(PMTYPE, enter_quick)(pmap_t pmap, vm_offset_t va, vm_page_t m,
4145     vm_prot_t prot)
4146 {
4147 
4148 	rw_wlock(&pvh_global_lock);
4149 	PMAP_LOCK(pmap);
4150 	(void)pmap_enter_quick_locked(pmap, va, m, prot, NULL);
4151 	rw_wunlock(&pvh_global_lock);
4152 	PMAP_UNLOCK(pmap);
4153 }
4154 
4155 static vm_page_t
pmap_enter_quick_locked(pmap_t pmap,vm_offset_t va,vm_page_t m,vm_prot_t prot,vm_page_t mpte)4156 pmap_enter_quick_locked(pmap_t pmap, vm_offset_t va, vm_page_t m,
4157     vm_prot_t prot, vm_page_t mpte)
4158 {
4159 	pt_entry_t newpte, *pte;
4160 	pd_entry_t *pde;
4161 
4162 	KASSERT(pmap != kernel_pmap || !VA_IS_CLEANMAP(va) ||
4163 	    (m->oflags & VPO_UNMANAGED) != 0,
4164 	    ("pmap_enter_quick_locked: managed mapping within the clean submap"));
4165 	rw_assert(&pvh_global_lock, RA_WLOCKED);
4166 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
4167 	pde = NULL;
4168 
4169 	/*
4170 	 * In the case that a page table page is not
4171 	 * resident, we are creating it here.
4172 	 */
4173 	if (pmap != kernel_pmap) {
4174 		u_int ptepindex;
4175 		pd_entry_t ptepa;
4176 
4177 		/*
4178 		 * Calculate pagetable page index
4179 		 */
4180 		ptepindex = va >> PDRSHIFT;
4181 		if (mpte && (mpte->pindex == ptepindex)) {
4182 			mpte->ref_count++;
4183 		} else {
4184 			/*
4185 			 * Get the page directory entry
4186 			 */
4187 			pde = &pmap->pm_pdir[ptepindex];
4188 			ptepa = *pde;
4189 
4190 			/*
4191 			 * If the page table page is mapped, we just increment
4192 			 * the hold count, and activate it.
4193 			 */
4194 			if (ptepa) {
4195 				if (ptepa & PG_PS)
4196 					return (NULL);
4197 				mpte = PHYS_TO_VM_PAGE(ptepa & PG_FRAME);
4198 				mpte->ref_count++;
4199 			} else {
4200 				mpte = _pmap_allocpte(pmap, ptepindex,
4201 				    PMAP_ENTER_NOSLEEP);
4202 				if (mpte == NULL)
4203 					return (mpte);
4204 			}
4205 		}
4206 	} else {
4207 		mpte = NULL;
4208 	}
4209 
4210 	sched_pin();
4211 	pte = pmap_pte_quick(pmap, va);
4212 	if (*pte) {
4213 		if (mpte != NULL)
4214 			mpte->ref_count--;
4215 		sched_unpin();
4216 		return (NULL);
4217 	}
4218 
4219 	/*
4220 	 * Enter on the PV list if part of our managed memory.
4221 	 */
4222 	if ((m->oflags & VPO_UNMANAGED) == 0 &&
4223 	    !pmap_try_insert_pv_entry(pmap, va, m)) {
4224 		if (mpte != NULL)
4225 			pmap_abort_ptp(pmap, va, mpte);
4226 		sched_unpin();
4227 		return (NULL);
4228 	}
4229 
4230 	/*
4231 	 * Increment counters
4232 	 */
4233 	pmap->pm_stats.resident_count++;
4234 
4235 	newpte = VM_PAGE_TO_PHYS(m) | PG_V |
4236 	    pmap_cache_bits(pmap, m->md.pat_mode, false);
4237 	if ((m->oflags & VPO_UNMANAGED) == 0)
4238 		newpte |= PG_MANAGED;
4239 #ifdef PMAP_PAE_COMP
4240 	if ((prot & VM_PROT_EXECUTE) == 0 && !i386_read_exec)
4241 		newpte |= pg_nx;
4242 #endif
4243 	if (pmap != kernel_pmap)
4244 		newpte |= PG_U;
4245 	pte_store_zero(pte, newpte);
4246 
4247 #if VM_NRESERVLEVEL > 0
4248 	/*
4249 	 * If both the PTP and the reservation are fully populated, then
4250 	 * attempt promotion.
4251 	 */
4252 	if ((mpte == NULL || mpte->ref_count == NPTEPG) &&
4253 	    (m->flags & PG_FICTITIOUS) == 0 &&
4254 	    vm_reserv_level_iffullpop(m) == 0) {
4255 		if (pde == NULL)
4256 			pde = pmap_pde(pmap, va);
4257 
4258 		/*
4259 		 * If promotion succeeds, then the next call to this function
4260 		 * should not be given the unmapped PTP as a hint.
4261 		 */
4262 		if (pmap_promote_pde(pmap, pde, va, mpte))
4263 			mpte = NULL;
4264 	}
4265 #endif
4266 
4267 	sched_unpin();
4268 	return (mpte);
4269 }
4270 
4271 /*
4272  * Make a temporary mapping for a physical address.  This is only intended
4273  * to be used for panic dumps.
4274  */
4275 static void *
__CONCAT(PMTYPE,kenter_temporary)4276 __CONCAT(PMTYPE, kenter_temporary)(vm_paddr_t pa, int i)
4277 {
4278 	vm_offset_t va;
4279 
4280 	va = (vm_offset_t)crashdumpmap + (i * PAGE_SIZE);
4281 	pmap_kenter(va, pa);
4282 	invlpg(va);
4283 	return ((void *)crashdumpmap);
4284 }
4285 
4286 /*
4287  * This code maps large physical mmap regions into the
4288  * processor address space.  Note that some shortcuts
4289  * are taken, but the code works.
4290  */
4291 static void
__CONCAT(PMTYPE,object_init_pt)4292 __CONCAT(PMTYPE, object_init_pt)(pmap_t pmap, vm_offset_t addr,
4293     vm_object_t object, vm_pindex_t pindex, vm_size_t size)
4294 {
4295 	pd_entry_t *pde;
4296 	vm_paddr_t pa, ptepa;
4297 	vm_page_t p;
4298 	int pat_mode;
4299 
4300 	VM_OBJECT_ASSERT_WLOCKED(object);
4301 	KASSERT(object->type == OBJT_DEVICE || object->type == OBJT_SG,
4302 	    ("pmap_object_init_pt: non-device object"));
4303 	if (pg_ps_enabled &&
4304 	    (addr & (NBPDR - 1)) == 0 && (size & (NBPDR - 1)) == 0) {
4305 		if (!vm_object_populate(object, pindex, pindex + atop(size)))
4306 			return;
4307 		p = vm_page_lookup(object, pindex);
4308 		KASSERT(vm_page_all_valid(p),
4309 		    ("pmap_object_init_pt: invalid page %p", p));
4310 		pat_mode = p->md.pat_mode;
4311 
4312 		/*
4313 		 * Abort the mapping if the first page is not physically
4314 		 * aligned to a 2/4MB page boundary.
4315 		 */
4316 		ptepa = VM_PAGE_TO_PHYS(p);
4317 		if (ptepa & (NBPDR - 1))
4318 			return;
4319 
4320 		/*
4321 		 * Skip the first page.  Abort the mapping if the rest of
4322 		 * the pages are not physically contiguous or have differing
4323 		 * memory attributes.
4324 		 */
4325 		p = TAILQ_NEXT(p, listq);
4326 		for (pa = ptepa + PAGE_SIZE; pa < ptepa + size;
4327 		    pa += PAGE_SIZE) {
4328 			KASSERT(vm_page_all_valid(p),
4329 			    ("pmap_object_init_pt: invalid page %p", p));
4330 			if (pa != VM_PAGE_TO_PHYS(p) ||
4331 			    pat_mode != p->md.pat_mode)
4332 				return;
4333 			p = TAILQ_NEXT(p, listq);
4334 		}
4335 
4336 		/*
4337 		 * Map using 2/4MB pages.  Since "ptepa" is 2/4M aligned and
4338 		 * "size" is a multiple of 2/4M, adding the PAT setting to
4339 		 * "pa" will not affect the termination of this loop.
4340 		 */
4341 		PMAP_LOCK(pmap);
4342 		for (pa = ptepa | pmap_cache_bits(pmap, pat_mode, true);
4343 		    pa < ptepa + size; pa += NBPDR) {
4344 			pde = pmap_pde(pmap, addr);
4345 			if (*pde == 0) {
4346 				pde_store(pde, pa | PG_PS | PG_M | PG_A |
4347 				    PG_U | PG_RW | PG_V);
4348 				pmap->pm_stats.resident_count += NBPDR /
4349 				    PAGE_SIZE;
4350 				pmap_pde_mappings++;
4351 			}
4352 			/* Else continue on if the PDE is already valid. */
4353 			addr += NBPDR;
4354 		}
4355 		PMAP_UNLOCK(pmap);
4356 	}
4357 }
4358 
4359 /*
4360  *	Clear the wired attribute from the mappings for the specified range of
4361  *	addresses in the given pmap.  Every valid mapping within that range
4362  *	must have the wired attribute set.  In contrast, invalid mappings
4363  *	cannot have the wired attribute set, so they are ignored.
4364  *
4365  *	The wired attribute of the page table entry is not a hardware feature,
4366  *	so there is no need to invalidate any TLB entries.
4367  */
4368 static void
__CONCAT(PMTYPE,unwire)4369 __CONCAT(PMTYPE, unwire)(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
4370 {
4371 	vm_offset_t pdnxt;
4372 	pd_entry_t *pde;
4373 	pt_entry_t *pte;
4374 	bool pv_lists_locked;
4375 
4376 	if (pmap_is_current(pmap))
4377 		pv_lists_locked = false;
4378 	else {
4379 		pv_lists_locked = true;
4380 resume:
4381 		rw_wlock(&pvh_global_lock);
4382 		sched_pin();
4383 	}
4384 	PMAP_LOCK(pmap);
4385 	for (; sva < eva; sva = pdnxt) {
4386 		pdnxt = (sva + NBPDR) & ~PDRMASK;
4387 		if (pdnxt < sva)
4388 			pdnxt = eva;
4389 		pde = pmap_pde(pmap, sva);
4390 		if ((*pde & PG_V) == 0)
4391 			continue;
4392 		if ((*pde & PG_PS) != 0) {
4393 			if ((*pde & PG_W) == 0)
4394 				panic("pmap_unwire: pde %#jx is missing PG_W",
4395 				    (uintmax_t)*pde);
4396 
4397 			/*
4398 			 * Are we unwiring the entire large page?  If not,
4399 			 * demote the mapping and fall through.
4400 			 */
4401 			if (sva + NBPDR == pdnxt && eva >= pdnxt) {
4402 				/*
4403 				 * Regardless of whether a pde (or pte) is 32
4404 				 * or 64 bits in size, PG_W is among the least
4405 				 * significant 32 bits.
4406 				 */
4407 				atomic_clear_int((u_int *)pde, PG_W);
4408 				pmap->pm_stats.wired_count -= NBPDR /
4409 				    PAGE_SIZE;
4410 				continue;
4411 			} else {
4412 				if (!pv_lists_locked) {
4413 					pv_lists_locked = true;
4414 					if (!rw_try_wlock(&pvh_global_lock)) {
4415 						PMAP_UNLOCK(pmap);
4416 						/* Repeat sva. */
4417 						goto resume;
4418 					}
4419 					sched_pin();
4420 				}
4421 				if (!pmap_demote_pde(pmap, pde, sva))
4422 					panic("pmap_unwire: demotion failed");
4423 			}
4424 		}
4425 		if (pdnxt > eva)
4426 			pdnxt = eva;
4427 		for (pte = pmap_pte_quick(pmap, sva); sva != pdnxt; pte++,
4428 		    sva += PAGE_SIZE) {
4429 			if ((*pte & PG_V) == 0)
4430 				continue;
4431 			if ((*pte & PG_W) == 0)
4432 				panic("pmap_unwire: pte %#jx is missing PG_W",
4433 				    (uintmax_t)*pte);
4434 
4435 			/*
4436 			 * PG_W must be cleared atomically.  Although the pmap
4437 			 * lock synchronizes access to PG_W, another processor
4438 			 * could be setting PG_M and/or PG_A concurrently.
4439 			 *
4440 			 * PG_W is among the least significant 32 bits.
4441 			 */
4442 			atomic_clear_int((u_int *)pte, PG_W);
4443 			pmap->pm_stats.wired_count--;
4444 		}
4445 	}
4446 	if (pv_lists_locked) {
4447 		sched_unpin();
4448 		rw_wunlock(&pvh_global_lock);
4449 	}
4450 	PMAP_UNLOCK(pmap);
4451 }
4452 
4453 /*
4454  *	Copy the range specified by src_addr/len
4455  *	from the source map to the range dst_addr/len
4456  *	in the destination map.
4457  *
4458  *	This routine is only advisory and need not do anything.  Since
4459  *	current pmap is always the kernel pmap when executing in
4460  *	kernel, and we do not copy from the kernel pmap to a user
4461  *	pmap, this optimization is not usable in 4/4G full split i386
4462  *	world.
4463  */
4464 
4465 static void
__CONCAT(PMTYPE,copy)4466 __CONCAT(PMTYPE, copy)(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr,
4467     vm_size_t len, vm_offset_t src_addr)
4468 {
4469 	pt_entry_t *src_pte, *dst_pte, ptetemp;
4470 	pd_entry_t srcptepaddr;
4471 	vm_page_t dstmpte, srcmpte;
4472 	vm_offset_t addr, end_addr, pdnxt;
4473 	u_int ptepindex;
4474 
4475 	if (dst_addr != src_addr)
4476 		return;
4477 
4478 	end_addr = src_addr + len;
4479 
4480 	rw_wlock(&pvh_global_lock);
4481 	if (dst_pmap < src_pmap) {
4482 		PMAP_LOCK(dst_pmap);
4483 		PMAP_LOCK(src_pmap);
4484 	} else {
4485 		PMAP_LOCK(src_pmap);
4486 		PMAP_LOCK(dst_pmap);
4487 	}
4488 	sched_pin();
4489 	for (addr = src_addr; addr < end_addr; addr = pdnxt) {
4490 		KASSERT(addr < PMAP_TRM_MIN_ADDRESS,
4491 		    ("pmap_copy: invalid to pmap_copy the trampoline"));
4492 
4493 		pdnxt = (addr + NBPDR) & ~PDRMASK;
4494 		if (pdnxt < addr)
4495 			pdnxt = end_addr;
4496 		ptepindex = addr >> PDRSHIFT;
4497 
4498 		srcptepaddr = src_pmap->pm_pdir[ptepindex];
4499 		if (srcptepaddr == 0)
4500 			continue;
4501 
4502 		if (srcptepaddr & PG_PS) {
4503 			if ((addr & PDRMASK) != 0 || addr + NBPDR > end_addr)
4504 				continue;
4505 			if (dst_pmap->pm_pdir[ptepindex] == 0 &&
4506 			    ((srcptepaddr & PG_MANAGED) == 0 ||
4507 			    pmap_pv_insert_pde(dst_pmap, addr, srcptepaddr,
4508 			    PMAP_ENTER_NORECLAIM))) {
4509 				dst_pmap->pm_pdir[ptepindex] = srcptepaddr &
4510 				    ~PG_W;
4511 				dst_pmap->pm_stats.resident_count +=
4512 				    NBPDR / PAGE_SIZE;
4513 				pmap_pde_mappings++;
4514 			}
4515 			continue;
4516 		}
4517 
4518 		srcmpte = PHYS_TO_VM_PAGE(srcptepaddr & PG_FRAME);
4519 		KASSERT(srcmpte->ref_count > 0,
4520 		    ("pmap_copy: source page table page is unused"));
4521 
4522 		if (pdnxt > end_addr)
4523 			pdnxt = end_addr;
4524 
4525 		src_pte = pmap_pte_quick3(src_pmap, addr);
4526 		while (addr < pdnxt) {
4527 			ptetemp = *src_pte;
4528 			/*
4529 			 * we only virtual copy managed pages
4530 			 */
4531 			if ((ptetemp & PG_MANAGED) != 0) {
4532 				dstmpte = pmap_allocpte(dst_pmap, addr,
4533 				    PMAP_ENTER_NOSLEEP);
4534 				if (dstmpte == NULL)
4535 					goto out;
4536 				dst_pte = pmap_pte_quick(dst_pmap, addr);
4537 				if (*dst_pte == 0 &&
4538 				    pmap_try_insert_pv_entry(dst_pmap, addr,
4539 				    PHYS_TO_VM_PAGE(ptetemp & PG_FRAME))) {
4540 					/*
4541 					 * Clear the wired, modified, and
4542 					 * accessed (referenced) bits
4543 					 * during the copy.
4544 					 */
4545 					*dst_pte = ptetemp & ~(PG_W | PG_M |
4546 					    PG_A);
4547 					dst_pmap->pm_stats.resident_count++;
4548 				} else {
4549 					pmap_abort_ptp(dst_pmap, addr, dstmpte);
4550 					goto out;
4551 				}
4552 				if (dstmpte->ref_count >= srcmpte->ref_count)
4553 					break;
4554 			}
4555 			addr += PAGE_SIZE;
4556 			src_pte++;
4557 		}
4558 	}
4559 out:
4560 	sched_unpin();
4561 	rw_wunlock(&pvh_global_lock);
4562 	PMAP_UNLOCK(src_pmap);
4563 	PMAP_UNLOCK(dst_pmap);
4564 }
4565 
4566 /*
4567  * Zero 1 page of virtual memory mapped from a hardware page by the caller.
4568  */
4569 static __inline void
pagezero(void * page)4570 pagezero(void *page)
4571 {
4572 #if defined(I686_CPU)
4573 	if (cpu_class == CPUCLASS_686) {
4574 		if (cpu_feature & CPUID_SSE2)
4575 			sse2_pagezero(page);
4576 		else
4577 			i686_pagezero(page);
4578 	} else
4579 #endif
4580 		bzero(page, PAGE_SIZE);
4581 }
4582 
4583 /*
4584  * Zero the specified hardware page.
4585  */
4586 static void
__CONCAT(PMTYPE,zero_page)4587 __CONCAT(PMTYPE, zero_page)(vm_page_t m)
4588 {
4589 	pt_entry_t *cmap_pte2;
4590 	struct pcpu *pc;
4591 
4592 	sched_pin();
4593 	pc = get_pcpu();
4594 	cmap_pte2 = pc->pc_cmap_pte2;
4595 	mtx_lock(&pc->pc_cmap_lock);
4596 	if (*cmap_pte2)
4597 		panic("pmap_zero_page: CMAP2 busy");
4598 	*cmap_pte2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(m) | PG_A | PG_M |
4599 	    pmap_cache_bits(kernel_pmap, m->md.pat_mode, false);
4600 	invlcaddr(pc->pc_cmap_addr2);
4601 	pagezero(pc->pc_cmap_addr2);
4602 	*cmap_pte2 = 0;
4603 
4604 	/*
4605 	 * Unpin the thread before releasing the lock.  Otherwise the thread
4606 	 * could be rescheduled while still bound to the current CPU, only
4607 	 * to unpin itself immediately upon resuming execution.
4608 	 */
4609 	sched_unpin();
4610 	mtx_unlock(&pc->pc_cmap_lock);
4611 }
4612 
4613 /*
4614  * Zero an area within a single hardware page.  off and size must not
4615  * cover an area beyond a single hardware page.
4616  */
4617 static void
__CONCAT(PMTYPE,zero_page_area)4618 __CONCAT(PMTYPE, zero_page_area)(vm_page_t m, int off, int size)
4619 {
4620 	pt_entry_t *cmap_pte2;
4621 	struct pcpu *pc;
4622 
4623 	sched_pin();
4624 	pc = get_pcpu();
4625 	cmap_pte2 = pc->pc_cmap_pte2;
4626 	mtx_lock(&pc->pc_cmap_lock);
4627 	if (*cmap_pte2)
4628 		panic("pmap_zero_page_area: CMAP2 busy");
4629 	*cmap_pte2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(m) | PG_A | PG_M |
4630 	    pmap_cache_bits(kernel_pmap, m->md.pat_mode, false);
4631 	invlcaddr(pc->pc_cmap_addr2);
4632 	if (off == 0 && size == PAGE_SIZE)
4633 		pagezero(pc->pc_cmap_addr2);
4634 	else
4635 		bzero(pc->pc_cmap_addr2 + off, size);
4636 	*cmap_pte2 = 0;
4637 	sched_unpin();
4638 	mtx_unlock(&pc->pc_cmap_lock);
4639 }
4640 
4641 /*
4642  * Copy 1 specified hardware page to another.
4643  */
4644 static void
__CONCAT(PMTYPE,copy_page)4645 __CONCAT(PMTYPE, copy_page)(vm_page_t src, vm_page_t dst)
4646 {
4647 	pt_entry_t *cmap_pte1, *cmap_pte2;
4648 	struct pcpu *pc;
4649 
4650 	sched_pin();
4651 	pc = get_pcpu();
4652 	cmap_pte1 = pc->pc_cmap_pte1;
4653 	cmap_pte2 = pc->pc_cmap_pte2;
4654 	mtx_lock(&pc->pc_cmap_lock);
4655 	if (*cmap_pte1)
4656 		panic("pmap_copy_page: CMAP1 busy");
4657 	if (*cmap_pte2)
4658 		panic("pmap_copy_page: CMAP2 busy");
4659 	*cmap_pte1 = PG_V | VM_PAGE_TO_PHYS(src) | PG_A |
4660 	    pmap_cache_bits(kernel_pmap, src->md.pat_mode, false);
4661 	invlcaddr(pc->pc_cmap_addr1);
4662 	*cmap_pte2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(dst) | PG_A | PG_M |
4663 	    pmap_cache_bits(kernel_pmap, dst->md.pat_mode, false);
4664 	invlcaddr(pc->pc_cmap_addr2);
4665 	bcopy(pc->pc_cmap_addr1, pc->pc_cmap_addr2, PAGE_SIZE);
4666 	*cmap_pte1 = 0;
4667 	*cmap_pte2 = 0;
4668 	sched_unpin();
4669 	mtx_unlock(&pc->pc_cmap_lock);
4670 }
4671 
4672 static void
__CONCAT(PMTYPE,copy_pages)4673 __CONCAT(PMTYPE, copy_pages)(vm_page_t ma[], vm_offset_t a_offset,
4674     vm_page_t mb[], vm_offset_t b_offset, int xfersize)
4675 {
4676 	vm_page_t a_pg, b_pg;
4677 	char *a_cp, *b_cp;
4678 	vm_offset_t a_pg_offset, b_pg_offset;
4679 	pt_entry_t *cmap_pte1, *cmap_pte2;
4680 	struct pcpu *pc;
4681 	int cnt;
4682 
4683 	sched_pin();
4684 	pc = get_pcpu();
4685 	cmap_pte1 = pc->pc_cmap_pte1;
4686 	cmap_pte2 = pc->pc_cmap_pte2;
4687 	mtx_lock(&pc->pc_cmap_lock);
4688 	if (*cmap_pte1 != 0)
4689 		panic("pmap_copy_pages: CMAP1 busy");
4690 	if (*cmap_pte2 != 0)
4691 		panic("pmap_copy_pages: CMAP2 busy");
4692 	while (xfersize > 0) {
4693 		a_pg = ma[a_offset >> PAGE_SHIFT];
4694 		a_pg_offset = a_offset & PAGE_MASK;
4695 		cnt = min(xfersize, PAGE_SIZE - a_pg_offset);
4696 		b_pg = mb[b_offset >> PAGE_SHIFT];
4697 		b_pg_offset = b_offset & PAGE_MASK;
4698 		cnt = min(cnt, PAGE_SIZE - b_pg_offset);
4699 		*cmap_pte1 = PG_V | VM_PAGE_TO_PHYS(a_pg) | PG_A |
4700 		    pmap_cache_bits(kernel_pmap, a_pg->md.pat_mode, false);
4701 		invlcaddr(pc->pc_cmap_addr1);
4702 		*cmap_pte2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(b_pg) | PG_A |
4703 		    PG_M | pmap_cache_bits(kernel_pmap, b_pg->md.pat_mode,
4704 		    false);
4705 		invlcaddr(pc->pc_cmap_addr2);
4706 		a_cp = pc->pc_cmap_addr1 + a_pg_offset;
4707 		b_cp = pc->pc_cmap_addr2 + b_pg_offset;
4708 		bcopy(a_cp, b_cp, cnt);
4709 		a_offset += cnt;
4710 		b_offset += cnt;
4711 		xfersize -= cnt;
4712 	}
4713 	*cmap_pte1 = 0;
4714 	*cmap_pte2 = 0;
4715 	sched_unpin();
4716 	mtx_unlock(&pc->pc_cmap_lock);
4717 }
4718 
4719 /*
4720  * Returns true if the pmap's pv is one of the first
4721  * 16 pvs linked to from this page.  This count may
4722  * be changed upwards or downwards in the future; it
4723  * is only necessary that true be returned for a small
4724  * subset of pmaps for proper page aging.
4725  */
4726 static bool
__CONCAT(PMTYPE,page_exists_quick)4727 __CONCAT(PMTYPE, page_exists_quick)(pmap_t pmap, vm_page_t m)
4728 {
4729 	struct md_page *pvh;
4730 	pv_entry_t pv;
4731 	int loops = 0;
4732 	bool rv;
4733 
4734 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
4735 	    ("pmap_page_exists_quick: page %p is not managed", m));
4736 	rv = false;
4737 	rw_wlock(&pvh_global_lock);
4738 	TAILQ_FOREACH(pv, &m->md.pv_list, pv_next) {
4739 		if (PV_PMAP(pv) == pmap) {
4740 			rv = true;
4741 			break;
4742 		}
4743 		loops++;
4744 		if (loops >= 16)
4745 			break;
4746 	}
4747 	if (!rv && loops < 16 && (m->flags & PG_FICTITIOUS) == 0) {
4748 		pvh = pa_to_pvh(VM_PAGE_TO_PHYS(m));
4749 		TAILQ_FOREACH(pv, &pvh->pv_list, pv_next) {
4750 			if (PV_PMAP(pv) == pmap) {
4751 				rv = true;
4752 				break;
4753 			}
4754 			loops++;
4755 			if (loops >= 16)
4756 				break;
4757 		}
4758 	}
4759 	rw_wunlock(&pvh_global_lock);
4760 	return (rv);
4761 }
4762 
4763 /*
4764  *	pmap_page_wired_mappings:
4765  *
4766  *	Return the number of managed mappings to the given physical page
4767  *	that are wired.
4768  */
4769 static int
__CONCAT(PMTYPE,page_wired_mappings)4770 __CONCAT(PMTYPE, page_wired_mappings)(vm_page_t m)
4771 {
4772 	int count;
4773 
4774 	count = 0;
4775 	if ((m->oflags & VPO_UNMANAGED) != 0)
4776 		return (count);
4777 	rw_wlock(&pvh_global_lock);
4778 	count = pmap_pvh_wired_mappings(&m->md, count);
4779 	if ((m->flags & PG_FICTITIOUS) == 0) {
4780 	    count = pmap_pvh_wired_mappings(pa_to_pvh(VM_PAGE_TO_PHYS(m)),
4781 	        count);
4782 	}
4783 	rw_wunlock(&pvh_global_lock);
4784 	return (count);
4785 }
4786 
4787 /*
4788  *	pmap_pvh_wired_mappings:
4789  *
4790  *	Return the updated number "count" of managed mappings that are wired.
4791  */
4792 static int
pmap_pvh_wired_mappings(struct md_page * pvh,int count)4793 pmap_pvh_wired_mappings(struct md_page *pvh, int count)
4794 {
4795 	pmap_t pmap;
4796 	pt_entry_t *pte;
4797 	pv_entry_t pv;
4798 
4799 	rw_assert(&pvh_global_lock, RA_WLOCKED);
4800 	sched_pin();
4801 	TAILQ_FOREACH(pv, &pvh->pv_list, pv_next) {
4802 		pmap = PV_PMAP(pv);
4803 		PMAP_LOCK(pmap);
4804 		pte = pmap_pte_quick(pmap, pv->pv_va);
4805 		if ((*pte & PG_W) != 0)
4806 			count++;
4807 		PMAP_UNLOCK(pmap);
4808 	}
4809 	sched_unpin();
4810 	return (count);
4811 }
4812 
4813 /*
4814  * Returns true if the given page is mapped individually or as part of
4815  * a 4mpage.  Otherwise, returns false.
4816  */
4817 static bool
__CONCAT(PMTYPE,page_is_mapped)4818 __CONCAT(PMTYPE, page_is_mapped)(vm_page_t m)
4819 {
4820 	bool rv;
4821 
4822 	if ((m->oflags & VPO_UNMANAGED) != 0)
4823 		return (false);
4824 	rw_wlock(&pvh_global_lock);
4825 	rv = !TAILQ_EMPTY(&m->md.pv_list) ||
4826 	    ((m->flags & PG_FICTITIOUS) == 0 &&
4827 	    !TAILQ_EMPTY(&pa_to_pvh(VM_PAGE_TO_PHYS(m))->pv_list));
4828 	rw_wunlock(&pvh_global_lock);
4829 	return (rv);
4830 }
4831 
4832 /*
4833  * Remove all pages from specified address space
4834  * this aids process exit speeds.  Also, this code
4835  * is special cased for current process only, but
4836  * can have the more generic (and slightly slower)
4837  * mode enabled.  This is much faster than pmap_remove
4838  * in the case of running down an entire address space.
4839  */
4840 static void
__CONCAT(PMTYPE,remove_pages)4841 __CONCAT(PMTYPE, remove_pages)(pmap_t pmap)
4842 {
4843 	pt_entry_t *pte, tpte;
4844 	vm_page_t m, mpte, mt;
4845 	pv_entry_t pv;
4846 	struct md_page *pvh;
4847 	struct pv_chunk *pc, *npc;
4848 	struct spglist free;
4849 	int field, idx;
4850 	int32_t bit;
4851 	uint32_t inuse, bitmask;
4852 	int allfree;
4853 
4854 	if (pmap != PCPU_GET(curpmap)) {
4855 		printf("warning: pmap_remove_pages called with non-current pmap\n");
4856 		return;
4857 	}
4858 	SLIST_INIT(&free);
4859 	rw_wlock(&pvh_global_lock);
4860 	PMAP_LOCK(pmap);
4861 	sched_pin();
4862 	TAILQ_FOREACH_SAFE(pc, &pmap->pm_pvchunk, pc_list, npc) {
4863 		KASSERT(pc->pc_pmap == pmap, ("Wrong pmap %p %p", pmap,
4864 		    pc->pc_pmap));
4865 		allfree = 1;
4866 		for (field = 0; field < _NPCM; field++) {
4867 			inuse = ~pc->pc_map[field] & pc_freemask[field];
4868 			while (inuse != 0) {
4869 				bit = bsfl(inuse);
4870 				bitmask = 1UL << bit;
4871 				idx = field * 32 + bit;
4872 				pv = &pc->pc_pventry[idx];
4873 				inuse &= ~bitmask;
4874 
4875 				pte = pmap_pde(pmap, pv->pv_va);
4876 				tpte = *pte;
4877 				if ((tpte & PG_PS) == 0) {
4878 					pte = pmap_pte_quick(pmap, pv->pv_va);
4879 					tpte = *pte & ~PG_PTE_PAT;
4880 				}
4881 
4882 				if (tpte == 0) {
4883 					printf(
4884 					    "TPTE at %p  IS ZERO @ VA %08x\n",
4885 					    pte, pv->pv_va);
4886 					panic("bad pte");
4887 				}
4888 
4889 /*
4890  * We cannot remove wired pages from a process' mapping at this time
4891  */
4892 				if (tpte & PG_W) {
4893 					allfree = 0;
4894 					continue;
4895 				}
4896 
4897 				m = PHYS_TO_VM_PAGE(tpte & PG_FRAME);
4898 				KASSERT(m->phys_addr == (tpte & PG_FRAME),
4899 				    ("vm_page_t %p phys_addr mismatch %016jx %016jx",
4900 				    m, (uintmax_t)m->phys_addr,
4901 				    (uintmax_t)tpte));
4902 
4903 				KASSERT((m->flags & PG_FICTITIOUS) != 0 ||
4904 				    m < &vm_page_array[vm_page_array_size],
4905 				    ("pmap_remove_pages: bad tpte %#jx",
4906 				    (uintmax_t)tpte));
4907 
4908 				pte_clear(pte);
4909 
4910 				/*
4911 				 * Update the vm_page_t clean/reference bits.
4912 				 */
4913 				if ((tpte & (PG_M | PG_RW)) == (PG_M | PG_RW)) {
4914 					if ((tpte & PG_PS) != 0) {
4915 						for (mt = m; mt < &m[NBPDR / PAGE_SIZE]; mt++)
4916 							vm_page_dirty(mt);
4917 					} else
4918 						vm_page_dirty(m);
4919 				}
4920 
4921 				/* Mark free */
4922 				PV_STAT(pv_entry_frees++);
4923 				PV_STAT(pv_entry_spare++);
4924 				pv_entry_count--;
4925 				pc->pc_map[field] |= bitmask;
4926 				if ((tpte & PG_PS) != 0) {
4927 					pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE;
4928 					pvh = pa_to_pvh(tpte & PG_PS_FRAME);
4929 					TAILQ_REMOVE(&pvh->pv_list, pv, pv_next);
4930 					if (TAILQ_EMPTY(&pvh->pv_list)) {
4931 						for (mt = m; mt < &m[NBPDR / PAGE_SIZE]; mt++)
4932 							if (TAILQ_EMPTY(&mt->md.pv_list))
4933 								vm_page_aflag_clear(mt, PGA_WRITEABLE);
4934 					}
4935 					mpte = pmap_remove_pt_page(pmap, pv->pv_va);
4936 					if (mpte != NULL) {
4937 						KASSERT(vm_page_any_valid(mpte),
4938 						    ("pmap_remove_pages: pte page not promoted"));
4939 						pmap->pm_stats.resident_count--;
4940 						KASSERT(mpte->ref_count == NPTEPG,
4941 						    ("pmap_remove_pages: pte page ref count error"));
4942 						mpte->ref_count = 0;
4943 						pmap_add_delayed_free_list(mpte, &free, false);
4944 					}
4945 				} else {
4946 					pmap->pm_stats.resident_count--;
4947 					TAILQ_REMOVE(&m->md.pv_list, pv, pv_next);
4948 					if (TAILQ_EMPTY(&m->md.pv_list) &&
4949 					    (m->flags & PG_FICTITIOUS) == 0) {
4950 						pvh = pa_to_pvh(VM_PAGE_TO_PHYS(m));
4951 						if (TAILQ_EMPTY(&pvh->pv_list))
4952 							vm_page_aflag_clear(m, PGA_WRITEABLE);
4953 					}
4954 					pmap_unuse_pt(pmap, pv->pv_va, &free);
4955 				}
4956 			}
4957 		}
4958 		if (allfree) {
4959 			TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
4960 			free_pv_chunk(pc);
4961 		}
4962 	}
4963 	sched_unpin();
4964 	pmap_invalidate_all_int(pmap);
4965 	rw_wunlock(&pvh_global_lock);
4966 	PMAP_UNLOCK(pmap);
4967 	vm_page_free_pages_toq(&free, true);
4968 }
4969 
4970 /*
4971  *	pmap_is_modified:
4972  *
4973  *	Return whether or not the specified physical page was modified
4974  *	in any physical maps.
4975  */
4976 static bool
__CONCAT(PMTYPE,is_modified)4977 __CONCAT(PMTYPE, is_modified)(vm_page_t m)
4978 {
4979 	bool rv;
4980 
4981 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
4982 	    ("pmap_is_modified: page %p is not managed", m));
4983 
4984 	/*
4985 	 * If the page is not busied then this check is racy.
4986 	 */
4987 	if (!pmap_page_is_write_mapped(m))
4988 		return (false);
4989 	rw_wlock(&pvh_global_lock);
4990 	rv = pmap_is_modified_pvh(&m->md) ||
4991 	    ((m->flags & PG_FICTITIOUS) == 0 &&
4992 	    pmap_is_modified_pvh(pa_to_pvh(VM_PAGE_TO_PHYS(m))));
4993 	rw_wunlock(&pvh_global_lock);
4994 	return (rv);
4995 }
4996 
4997 /*
4998  * Returns true if any of the given mappings were used to modify
4999  * physical memory.  Otherwise, returns false.  Both page and 2mpage
5000  * mappings are supported.
5001  */
5002 static bool
pmap_is_modified_pvh(struct md_page * pvh)5003 pmap_is_modified_pvh(struct md_page *pvh)
5004 {
5005 	pv_entry_t pv;
5006 	pt_entry_t *pte;
5007 	pmap_t pmap;
5008 	bool rv;
5009 
5010 	rw_assert(&pvh_global_lock, RA_WLOCKED);
5011 	rv = false;
5012 	sched_pin();
5013 	TAILQ_FOREACH(pv, &pvh->pv_list, pv_next) {
5014 		pmap = PV_PMAP(pv);
5015 		PMAP_LOCK(pmap);
5016 		pte = pmap_pte_quick(pmap, pv->pv_va);
5017 		rv = (*pte & (PG_M | PG_RW)) == (PG_M | PG_RW);
5018 		PMAP_UNLOCK(pmap);
5019 		if (rv)
5020 			break;
5021 	}
5022 	sched_unpin();
5023 	return (rv);
5024 }
5025 
5026 /*
5027  *	pmap_is_prefaultable:
5028  *
5029  *	Return whether or not the specified virtual address is elgible
5030  *	for prefault.
5031  */
5032 static bool
__CONCAT(PMTYPE,is_prefaultable)5033 __CONCAT(PMTYPE, is_prefaultable)(pmap_t pmap, vm_offset_t addr)
5034 {
5035 	pd_entry_t pde;
5036 	bool rv;
5037 
5038 	rv = false;
5039 	PMAP_LOCK(pmap);
5040 	pde = *pmap_pde(pmap, addr);
5041 	if (pde != 0 && (pde & PG_PS) == 0)
5042 		rv = pmap_pte_ufast(pmap, addr, pde) == 0;
5043 	PMAP_UNLOCK(pmap);
5044 	return (rv);
5045 }
5046 
5047 /*
5048  *	pmap_is_referenced:
5049  *
5050  *	Return whether or not the specified physical page was referenced
5051  *	in any physical maps.
5052  */
5053 static bool
__CONCAT(PMTYPE,is_referenced)5054 __CONCAT(PMTYPE, is_referenced)(vm_page_t m)
5055 {
5056 	bool rv;
5057 
5058 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
5059 	    ("pmap_is_referenced: page %p is not managed", m));
5060 	rw_wlock(&pvh_global_lock);
5061 	rv = pmap_is_referenced_pvh(&m->md) ||
5062 	    ((m->flags & PG_FICTITIOUS) == 0 &&
5063 	    pmap_is_referenced_pvh(pa_to_pvh(VM_PAGE_TO_PHYS(m))));
5064 	rw_wunlock(&pvh_global_lock);
5065 	return (rv);
5066 }
5067 
5068 /*
5069  * Returns true if any of the given mappings were referenced and false
5070  * otherwise.  Both page and 4mpage mappings are supported.
5071  */
5072 static bool
pmap_is_referenced_pvh(struct md_page * pvh)5073 pmap_is_referenced_pvh(struct md_page *pvh)
5074 {
5075 	pv_entry_t pv;
5076 	pt_entry_t *pte;
5077 	pmap_t pmap;
5078 	bool rv;
5079 
5080 	rw_assert(&pvh_global_lock, RA_WLOCKED);
5081 	rv = false;
5082 	sched_pin();
5083 	TAILQ_FOREACH(pv, &pvh->pv_list, pv_next) {
5084 		pmap = PV_PMAP(pv);
5085 		PMAP_LOCK(pmap);
5086 		pte = pmap_pte_quick(pmap, pv->pv_va);
5087 		rv = (*pte & (PG_A | PG_V)) == (PG_A | PG_V);
5088 		PMAP_UNLOCK(pmap);
5089 		if (rv)
5090 			break;
5091 	}
5092 	sched_unpin();
5093 	return (rv);
5094 }
5095 
5096 /*
5097  * Clear the write and modified bits in each of the given page's mappings.
5098  */
5099 static void
__CONCAT(PMTYPE,remove_write)5100 __CONCAT(PMTYPE, remove_write)(vm_page_t m)
5101 {
5102 	struct md_page *pvh;
5103 	pv_entry_t next_pv, pv;
5104 	pmap_t pmap;
5105 	pd_entry_t *pde;
5106 	pt_entry_t oldpte, *pte;
5107 	vm_offset_t va;
5108 
5109 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
5110 	    ("pmap_remove_write: page %p is not managed", m));
5111 	vm_page_assert_busied(m);
5112 
5113 	if (!pmap_page_is_write_mapped(m))
5114 		return;
5115 	rw_wlock(&pvh_global_lock);
5116 	sched_pin();
5117 	if ((m->flags & PG_FICTITIOUS) != 0)
5118 		goto small_mappings;
5119 	pvh = pa_to_pvh(VM_PAGE_TO_PHYS(m));
5120 	TAILQ_FOREACH_SAFE(pv, &pvh->pv_list, pv_next, next_pv) {
5121 		va = pv->pv_va;
5122 		pmap = PV_PMAP(pv);
5123 		PMAP_LOCK(pmap);
5124 		pde = pmap_pde(pmap, va);
5125 		if ((*pde & PG_RW) != 0)
5126 			(void)pmap_demote_pde(pmap, pde, va);
5127 		PMAP_UNLOCK(pmap);
5128 	}
5129 small_mappings:
5130 	TAILQ_FOREACH(pv, &m->md.pv_list, pv_next) {
5131 		pmap = PV_PMAP(pv);
5132 		PMAP_LOCK(pmap);
5133 		pde = pmap_pde(pmap, pv->pv_va);
5134 		KASSERT((*pde & PG_PS) == 0, ("pmap_clear_write: found"
5135 		    " a 4mpage in page %p's pv list", m));
5136 		pte = pmap_pte_quick(pmap, pv->pv_va);
5137 retry:
5138 		oldpte = *pte;
5139 		if ((oldpte & PG_RW) != 0) {
5140 			/*
5141 			 * Regardless of whether a pte is 32 or 64 bits
5142 			 * in size, PG_RW and PG_M are among the least
5143 			 * significant 32 bits.
5144 			 */
5145 			if (!atomic_cmpset_int((u_int *)pte, oldpte,
5146 			    oldpte & ~(PG_RW | PG_M)))
5147 				goto retry;
5148 			if ((oldpte & PG_M) != 0)
5149 				vm_page_dirty(m);
5150 			pmap_invalidate_page_int(pmap, pv->pv_va);
5151 		}
5152 		PMAP_UNLOCK(pmap);
5153 	}
5154 	vm_page_aflag_clear(m, PGA_WRITEABLE);
5155 	sched_unpin();
5156 	rw_wunlock(&pvh_global_lock);
5157 }
5158 
5159 /*
5160  *	pmap_ts_referenced:
5161  *
5162  *	Return a count of reference bits for a page, clearing those bits.
5163  *	It is not necessary for every reference bit to be cleared, but it
5164  *	is necessary that 0 only be returned when there are truly no
5165  *	reference bits set.
5166  *
5167  *	As an optimization, update the page's dirty field if a modified bit is
5168  *	found while counting reference bits.  This opportunistic update can be
5169  *	performed at low cost and can eliminate the need for some future calls
5170  *	to pmap_is_modified().  However, since this function stops after
5171  *	finding PMAP_TS_REFERENCED_MAX reference bits, it may not detect some
5172  *	dirty pages.  Those dirty pages will only be detected by a future call
5173  *	to pmap_is_modified().
5174  */
5175 static int
__CONCAT(PMTYPE,ts_referenced)5176 __CONCAT(PMTYPE, ts_referenced)(vm_page_t m)
5177 {
5178 	struct md_page *pvh;
5179 	pv_entry_t pv, pvf;
5180 	pmap_t pmap;
5181 	pd_entry_t *pde;
5182 	pt_entry_t *pte;
5183 	vm_paddr_t pa;
5184 	int rtval = 0;
5185 
5186 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
5187 	    ("pmap_ts_referenced: page %p is not managed", m));
5188 	pa = VM_PAGE_TO_PHYS(m);
5189 	pvh = pa_to_pvh(pa);
5190 	rw_wlock(&pvh_global_lock);
5191 	sched_pin();
5192 	if ((m->flags & PG_FICTITIOUS) != 0 ||
5193 	    (pvf = TAILQ_FIRST(&pvh->pv_list)) == NULL)
5194 		goto small_mappings;
5195 	pv = pvf;
5196 	do {
5197 		pmap = PV_PMAP(pv);
5198 		PMAP_LOCK(pmap);
5199 		pde = pmap_pde(pmap, pv->pv_va);
5200 		if ((*pde & (PG_M | PG_RW)) == (PG_M | PG_RW)) {
5201 			/*
5202 			 * Although "*pde" is mapping a 2/4MB page, because
5203 			 * this function is called at a 4KB page granularity,
5204 			 * we only update the 4KB page under test.
5205 			 */
5206 			vm_page_dirty(m);
5207 		}
5208 		if ((*pde & PG_A) != 0) {
5209 			/*
5210 			 * Since this reference bit is shared by either 1024
5211 			 * or 512 4KB pages, it should not be cleared every
5212 			 * time it is tested.  Apply a simple "hash" function
5213 			 * on the physical page number, the virtual superpage
5214 			 * number, and the pmap address to select one 4KB page
5215 			 * out of the 1024 or 512 on which testing the
5216 			 * reference bit will result in clearing that bit.
5217 			 * This function is designed to avoid the selection of
5218 			 * the same 4KB page for every 2- or 4MB page mapping.
5219 			 *
5220 			 * On demotion, a mapping that hasn't been referenced
5221 			 * is simply destroyed.  To avoid the possibility of a
5222 			 * subsequent page fault on a demoted wired mapping,
5223 			 * always leave its reference bit set.  Moreover,
5224 			 * since the superpage is wired, the current state of
5225 			 * its reference bit won't affect page replacement.
5226 			 */
5227 			if ((((pa >> PAGE_SHIFT) ^ (pv->pv_va >> PDRSHIFT) ^
5228 			    (uintptr_t)pmap) & (NPTEPG - 1)) == 0 &&
5229 			    (*pde & PG_W) == 0) {
5230 				atomic_clear_int((u_int *)pde, PG_A);
5231 				pmap_invalidate_page_int(pmap, pv->pv_va);
5232 			}
5233 			rtval++;
5234 		}
5235 		PMAP_UNLOCK(pmap);
5236 		/* Rotate the PV list if it has more than one entry. */
5237 		if (TAILQ_NEXT(pv, pv_next) != NULL) {
5238 			TAILQ_REMOVE(&pvh->pv_list, pv, pv_next);
5239 			TAILQ_INSERT_TAIL(&pvh->pv_list, pv, pv_next);
5240 		}
5241 		if (rtval >= PMAP_TS_REFERENCED_MAX)
5242 			goto out;
5243 	} while ((pv = TAILQ_FIRST(&pvh->pv_list)) != pvf);
5244 small_mappings:
5245 	if ((pvf = TAILQ_FIRST(&m->md.pv_list)) == NULL)
5246 		goto out;
5247 	pv = pvf;
5248 	do {
5249 		pmap = PV_PMAP(pv);
5250 		PMAP_LOCK(pmap);
5251 		pde = pmap_pde(pmap, pv->pv_va);
5252 		KASSERT((*pde & PG_PS) == 0,
5253 		    ("pmap_ts_referenced: found a 4mpage in page %p's pv list",
5254 		    m));
5255 		pte = pmap_pte_quick(pmap, pv->pv_va);
5256 		if ((*pte & (PG_M | PG_RW)) == (PG_M | PG_RW))
5257 			vm_page_dirty(m);
5258 		if ((*pte & PG_A) != 0) {
5259 			atomic_clear_int((u_int *)pte, PG_A);
5260 			pmap_invalidate_page_int(pmap, pv->pv_va);
5261 			rtval++;
5262 		}
5263 		PMAP_UNLOCK(pmap);
5264 		/* Rotate the PV list if it has more than one entry. */
5265 		if (TAILQ_NEXT(pv, pv_next) != NULL) {
5266 			TAILQ_REMOVE(&m->md.pv_list, pv, pv_next);
5267 			TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_next);
5268 		}
5269 	} while ((pv = TAILQ_FIRST(&m->md.pv_list)) != pvf && rtval <
5270 	    PMAP_TS_REFERENCED_MAX);
5271 out:
5272 	sched_unpin();
5273 	rw_wunlock(&pvh_global_lock);
5274 	return (rtval);
5275 }
5276 
5277 /*
5278  *	Apply the given advice to the specified range of addresses within the
5279  *	given pmap.  Depending on the advice, clear the referenced and/or
5280  *	modified flags in each mapping and set the mapped page's dirty field.
5281  */
5282 static void
__CONCAT(PMTYPE,advise)5283 __CONCAT(PMTYPE, advise)(pmap_t pmap, vm_offset_t sva, vm_offset_t eva,
5284     int advice)
5285 {
5286 	pd_entry_t oldpde, *pde;
5287 	pt_entry_t *pte;
5288 	vm_offset_t va, pdnxt;
5289 	vm_page_t m;
5290 	bool anychanged, pv_lists_locked;
5291 
5292 	if (advice != MADV_DONTNEED && advice != MADV_FREE)
5293 		return;
5294 	if (pmap_is_current(pmap))
5295 		pv_lists_locked = false;
5296 	else {
5297 		pv_lists_locked = true;
5298 resume:
5299 		rw_wlock(&pvh_global_lock);
5300 		sched_pin();
5301 	}
5302 	anychanged = false;
5303 	PMAP_LOCK(pmap);
5304 	for (; sva < eva; sva = pdnxt) {
5305 		pdnxt = (sva + NBPDR) & ~PDRMASK;
5306 		if (pdnxt < sva)
5307 			pdnxt = eva;
5308 		pde = pmap_pde(pmap, sva);
5309 		oldpde = *pde;
5310 		if ((oldpde & PG_V) == 0)
5311 			continue;
5312 		else if ((oldpde & PG_PS) != 0) {
5313 			if ((oldpde & PG_MANAGED) == 0)
5314 				continue;
5315 			if (!pv_lists_locked) {
5316 				pv_lists_locked = true;
5317 				if (!rw_try_wlock(&pvh_global_lock)) {
5318 					if (anychanged)
5319 						pmap_invalidate_all_int(pmap);
5320 					PMAP_UNLOCK(pmap);
5321 					goto resume;
5322 				}
5323 				sched_pin();
5324 			}
5325 			if (!pmap_demote_pde(pmap, pde, sva)) {
5326 				/*
5327 				 * The large page mapping was destroyed.
5328 				 */
5329 				continue;
5330 			}
5331 
5332 			/*
5333 			 * Unless the page mappings are wired, remove the
5334 			 * mapping to a single page so that a subsequent
5335 			 * access may repromote.  Choosing the last page
5336 			 * within the address range [sva, min(pdnxt, eva))
5337 			 * generally results in more repromotions.  Since the
5338 			 * underlying page table page is fully populated, this
5339 			 * removal never frees a page table page.
5340 			 */
5341 			if ((oldpde & PG_W) == 0) {
5342 				va = eva;
5343 				if (va > pdnxt)
5344 					va = pdnxt;
5345 				va -= PAGE_SIZE;
5346 				KASSERT(va >= sva,
5347 				    ("pmap_advise: no address gap"));
5348 				pte = pmap_pte_quick(pmap, va);
5349 				KASSERT((*pte & PG_V) != 0,
5350 				    ("pmap_advise: invalid PTE"));
5351 				pmap_remove_pte(pmap, pte, va, NULL);
5352 				anychanged = true;
5353 			}
5354 		}
5355 		if (pdnxt > eva)
5356 			pdnxt = eva;
5357 		va = pdnxt;
5358 		for (pte = pmap_pte_quick(pmap, sva); sva != pdnxt; pte++,
5359 		    sva += PAGE_SIZE) {
5360 			if ((*pte & (PG_MANAGED | PG_V)) != (PG_MANAGED | PG_V))
5361 				goto maybe_invlrng;
5362 			else if ((*pte & (PG_M | PG_RW)) == (PG_M | PG_RW)) {
5363 				if (advice == MADV_DONTNEED) {
5364 					/*
5365 					 * Future calls to pmap_is_modified()
5366 					 * can be avoided by making the page
5367 					 * dirty now.
5368 					 */
5369 					m = PHYS_TO_VM_PAGE(*pte & PG_FRAME);
5370 					vm_page_dirty(m);
5371 				}
5372 				atomic_clear_int((u_int *)pte, PG_M | PG_A);
5373 			} else if ((*pte & PG_A) != 0)
5374 				atomic_clear_int((u_int *)pte, PG_A);
5375 			else
5376 				goto maybe_invlrng;
5377 			if ((*pte & PG_G) != 0) {
5378 				if (va == pdnxt)
5379 					va = sva;
5380 			} else
5381 				anychanged = true;
5382 			continue;
5383 maybe_invlrng:
5384 			if (va != pdnxt) {
5385 				pmap_invalidate_range_int(pmap, va, sva);
5386 				va = pdnxt;
5387 			}
5388 		}
5389 		if (va != pdnxt)
5390 			pmap_invalidate_range_int(pmap, va, sva);
5391 	}
5392 	if (anychanged)
5393 		pmap_invalidate_all_int(pmap);
5394 	if (pv_lists_locked) {
5395 		sched_unpin();
5396 		rw_wunlock(&pvh_global_lock);
5397 	}
5398 	PMAP_UNLOCK(pmap);
5399 }
5400 
5401 /*
5402  *	Clear the modify bits on the specified physical page.
5403  */
5404 static void
__CONCAT(PMTYPE,clear_modify)5405 __CONCAT(PMTYPE, clear_modify)(vm_page_t m)
5406 {
5407 	struct md_page *pvh;
5408 	pv_entry_t next_pv, pv;
5409 	pmap_t pmap;
5410 	pd_entry_t oldpde, *pde;
5411 	pt_entry_t *pte;
5412 	vm_offset_t va;
5413 
5414 	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
5415 	    ("pmap_clear_modify: page %p is not managed", m));
5416 	vm_page_assert_busied(m);
5417 
5418 	if (!pmap_page_is_write_mapped(m))
5419 		return;
5420 	rw_wlock(&pvh_global_lock);
5421 	sched_pin();
5422 	if ((m->flags & PG_FICTITIOUS) != 0)
5423 		goto small_mappings;
5424 	pvh = pa_to_pvh(VM_PAGE_TO_PHYS(m));
5425 	TAILQ_FOREACH_SAFE(pv, &pvh->pv_list, pv_next, next_pv) {
5426 		va = pv->pv_va;
5427 		pmap = PV_PMAP(pv);
5428 		PMAP_LOCK(pmap);
5429 		pde = pmap_pde(pmap, va);
5430 		oldpde = *pde;
5431 		/* If oldpde has PG_RW set, then it also has PG_M set. */
5432 		if ((oldpde & PG_RW) != 0 &&
5433 		    pmap_demote_pde(pmap, pde, va) &&
5434 		    (oldpde & PG_W) == 0) {
5435 			/*
5436 			 * Write protect the mapping to a single page so that
5437 			 * a subsequent write access may repromote.
5438 			 */
5439 			va += VM_PAGE_TO_PHYS(m) - (oldpde & PG_PS_FRAME);
5440 			pte = pmap_pte_quick(pmap, va);
5441 			/*
5442 			 * Regardless of whether a pte is 32 or 64 bits
5443 			 * in size, PG_RW and PG_M are among the least
5444 			 * significant 32 bits.
5445 			 */
5446 			atomic_clear_int((u_int *)pte, PG_M | PG_RW);
5447 			vm_page_dirty(m);
5448 			pmap_invalidate_page_int(pmap, va);
5449 		}
5450 		PMAP_UNLOCK(pmap);
5451 	}
5452 small_mappings:
5453 	TAILQ_FOREACH(pv, &m->md.pv_list, pv_next) {
5454 		pmap = PV_PMAP(pv);
5455 		PMAP_LOCK(pmap);
5456 		pde = pmap_pde(pmap, pv->pv_va);
5457 		KASSERT((*pde & PG_PS) == 0, ("pmap_clear_modify: found"
5458 		    " a 4mpage in page %p's pv list", m));
5459 		pte = pmap_pte_quick(pmap, pv->pv_va);
5460 		if ((*pte & (PG_M | PG_RW)) == (PG_M | PG_RW)) {
5461 			/*
5462 			 * Regardless of whether a pte is 32 or 64 bits
5463 			 * in size, PG_M is among the least significant
5464 			 * 32 bits.
5465 			 */
5466 			atomic_clear_int((u_int *)pte, PG_M);
5467 			pmap_invalidate_page_int(pmap, pv->pv_va);
5468 		}
5469 		PMAP_UNLOCK(pmap);
5470 	}
5471 	sched_unpin();
5472 	rw_wunlock(&pvh_global_lock);
5473 }
5474 
5475 /*
5476  * Miscellaneous support routines follow
5477  */
5478 
5479 /* Adjust the cache mode for a 4KB page mapped via a PTE. */
5480 static __inline void
pmap_pte_attr(pt_entry_t * pte,int cache_bits)5481 pmap_pte_attr(pt_entry_t *pte, int cache_bits)
5482 {
5483 	u_int opte, npte;
5484 
5485 	/*
5486 	 * The cache mode bits are all in the low 32-bits of the
5487 	 * PTE, so we can just spin on updating the low 32-bits.
5488 	 */
5489 	do {
5490 		opte = *(u_int *)pte;
5491 		npte = opte & ~PG_PTE_CACHE;
5492 		npte |= cache_bits;
5493 	} while (npte != opte && !atomic_cmpset_int((u_int *)pte, opte, npte));
5494 }
5495 
5496 /* Adjust the cache mode for a 2/4MB page mapped via a PDE. */
5497 static __inline void
pmap_pde_attr(pd_entry_t * pde,int cache_bits)5498 pmap_pde_attr(pd_entry_t *pde, int cache_bits)
5499 {
5500 	u_int opde, npde;
5501 
5502 	/*
5503 	 * The cache mode bits are all in the low 32-bits of the
5504 	 * PDE, so we can just spin on updating the low 32-bits.
5505 	 */
5506 	do {
5507 		opde = *(u_int *)pde;
5508 		npde = opde & ~PG_PDE_CACHE;
5509 		npde |= cache_bits;
5510 	} while (npde != opde && !atomic_cmpset_int((u_int *)pde, opde, npde));
5511 }
5512 
5513 /*
5514  * Map a set of physical memory pages into the kernel virtual
5515  * address space. Return a pointer to where it is mapped. This
5516  * routine is intended to be used for mapping device memory,
5517  * NOT real memory.
5518  */
5519 static void *
__CONCAT(PMTYPE,mapdev_attr)5520 __CONCAT(PMTYPE, mapdev_attr)(vm_paddr_t pa, vm_size_t size, int mode,
5521     int flags)
5522 {
5523 	struct pmap_preinit_mapping *ppim;
5524 	vm_offset_t va, offset;
5525 	vm_page_t m;
5526 	vm_size_t tmpsize;
5527 	int i;
5528 
5529 	offset = pa & PAGE_MASK;
5530 	size = round_page(offset + size);
5531 	pa = pa & PG_FRAME;
5532 
5533 	if (pa < PMAP_MAP_LOW && pa + size <= PMAP_MAP_LOW) {
5534 		va = pa + PMAP_MAP_LOW;
5535 		if ((flags & MAPDEV_SETATTR) == 0)
5536 			return ((void *)(va + offset));
5537 	} else if (!pmap_initialized) {
5538 		va = 0;
5539 		for (i = 0; i < PMAP_PREINIT_MAPPING_COUNT; i++) {
5540 			ppim = pmap_preinit_mapping + i;
5541 			if (ppim->va == 0) {
5542 				ppim->pa = pa;
5543 				ppim->sz = size;
5544 				ppim->mode = mode;
5545 				ppim->va = virtual_avail;
5546 				virtual_avail += size;
5547 				va = ppim->va;
5548 				break;
5549 			}
5550 		}
5551 		if (va == 0)
5552 			panic("%s: too many preinit mappings", __func__);
5553 	} else {
5554 		/*
5555 		 * If we have a preinit mapping, re-use it.
5556 		 */
5557 		for (i = 0; i < PMAP_PREINIT_MAPPING_COUNT; i++) {
5558 			ppim = pmap_preinit_mapping + i;
5559 			if (ppim->pa == pa && ppim->sz == size &&
5560 			    (ppim->mode == mode ||
5561 			    (flags & MAPDEV_SETATTR) == 0))
5562 				return ((void *)(ppim->va + offset));
5563 		}
5564 		va = kva_alloc(size);
5565 		if (va == 0)
5566 			panic("%s: Couldn't allocate KVA", __func__);
5567 	}
5568 	for (tmpsize = 0; tmpsize < size; tmpsize += PAGE_SIZE) {
5569 		if ((flags & MAPDEV_SETATTR) == 0 && pmap_initialized) {
5570 			m = PHYS_TO_VM_PAGE(pa);
5571 			if (m != NULL && VM_PAGE_TO_PHYS(m) == pa) {
5572 				pmap_kenter_attr(va + tmpsize, pa + tmpsize,
5573 				    m->md.pat_mode);
5574 				continue;
5575 			}
5576 		}
5577 		pmap_kenter_attr(va + tmpsize, pa + tmpsize, mode);
5578 	}
5579 	pmap_invalidate_range_int(kernel_pmap, va, va + tmpsize);
5580 	pmap_invalidate_cache_range(va, va + size);
5581 	return ((void *)(va + offset));
5582 }
5583 
5584 static void
__CONCAT(PMTYPE,unmapdev)5585 __CONCAT(PMTYPE, unmapdev)(void *p, vm_size_t size)
5586 {
5587 	struct pmap_preinit_mapping *ppim;
5588 	vm_offset_t offset, va;
5589 	int i;
5590 
5591 	va = (vm_offset_t)p;
5592 	if (va >= PMAP_MAP_LOW && va <= KERNBASE && va + size <= KERNBASE)
5593 		return;
5594 	offset = va & PAGE_MASK;
5595 	size = round_page(offset + size);
5596 	va = trunc_page(va);
5597 	for (i = 0; i < PMAP_PREINIT_MAPPING_COUNT; i++) {
5598 		ppim = pmap_preinit_mapping + i;
5599 		if (ppim->va == va && ppim->sz == size) {
5600 			if (pmap_initialized)
5601 				return;
5602 			ppim->pa = 0;
5603 			ppim->va = 0;
5604 			ppim->sz = 0;
5605 			ppim->mode = 0;
5606 			if (va + size == virtual_avail)
5607 				virtual_avail = va;
5608 			return;
5609 		}
5610 	}
5611 	if (pmap_initialized) {
5612 		pmap_qremove(va, atop(size));
5613 		kva_free(va, size);
5614 	}
5615 }
5616 
5617 /*
5618  * Sets the memory attribute for the specified page.
5619  */
5620 static void
__CONCAT(PMTYPE,page_set_memattr)5621 __CONCAT(PMTYPE, page_set_memattr)(vm_page_t m, vm_memattr_t ma)
5622 {
5623 
5624 	m->md.pat_mode = ma;
5625 	if ((m->flags & PG_FICTITIOUS) != 0)
5626 		return;
5627 
5628 	/*
5629 	 * If "m" is a normal page, flush it from the cache.
5630 	 * See pmap_invalidate_cache_range().
5631 	 *
5632 	 * First, try to find an existing mapping of the page by sf
5633 	 * buffer. sf_buf_invalidate_cache() modifies mapping and
5634 	 * flushes the cache.
5635 	 */
5636 	if (sf_buf_invalidate_cache(m))
5637 		return;
5638 
5639 	/*
5640 	 * If page is not mapped by sf buffer, but CPU does not
5641 	 * support self snoop, map the page transient and do
5642 	 * invalidation. In the worst case, whole cache is flushed by
5643 	 * pmap_invalidate_cache_range().
5644 	 */
5645 	if ((cpu_feature & CPUID_SS) == 0)
5646 		pmap_flush_page(m);
5647 }
5648 
5649 static void
__CONCAT(PMTYPE,flush_page)5650 __CONCAT(PMTYPE, flush_page)(vm_page_t m)
5651 {
5652 	pt_entry_t *cmap_pte2;
5653 	struct pcpu *pc;
5654 	vm_offset_t sva, eva;
5655 	bool useclflushopt;
5656 
5657 	useclflushopt = (cpu_stdext_feature & CPUID_STDEXT_CLFLUSHOPT) != 0;
5658 	if (useclflushopt || (cpu_feature & CPUID_CLFSH) != 0) {
5659 		sched_pin();
5660 		pc = get_pcpu();
5661 		cmap_pte2 = pc->pc_cmap_pte2;
5662 		mtx_lock(&pc->pc_cmap_lock);
5663 		if (*cmap_pte2)
5664 			panic("pmap_flush_page: CMAP2 busy");
5665 		*cmap_pte2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(m) |
5666 		    PG_A | PG_M | pmap_cache_bits(kernel_pmap, m->md.pat_mode,
5667 		    false);
5668 		invlcaddr(pc->pc_cmap_addr2);
5669 		sva = (vm_offset_t)pc->pc_cmap_addr2;
5670 		eva = sva + PAGE_SIZE;
5671 
5672 		/*
5673 		 * Use mfence or sfence despite the ordering implied by
5674 		 * mtx_{un,}lock() because clflush on non-Intel CPUs
5675 		 * and clflushopt are not guaranteed to be ordered by
5676 		 * any other instruction.
5677 		 */
5678 		if (useclflushopt)
5679 			sfence();
5680 		else if (cpu_vendor_id != CPU_VENDOR_INTEL)
5681 			mfence();
5682 		for (; sva < eva; sva += cpu_clflush_line_size) {
5683 			if (useclflushopt)
5684 				clflushopt(sva);
5685 			else
5686 				clflush(sva);
5687 		}
5688 		if (useclflushopt)
5689 			sfence();
5690 		else if (cpu_vendor_id != CPU_VENDOR_INTEL)
5691 			mfence();
5692 		*cmap_pte2 = 0;
5693 		sched_unpin();
5694 		mtx_unlock(&pc->pc_cmap_lock);
5695 	} else
5696 		pmap_invalidate_cache();
5697 }
5698 
5699 /*
5700  * Changes the specified virtual address range's memory type to that given by
5701  * the parameter "mode".  The specified virtual address range must be
5702  * completely contained within either the kernel map.
5703  *
5704  * Returns zero if the change completed successfully, and either EINVAL or
5705  * ENOMEM if the change failed.  Specifically, EINVAL is returned if some part
5706  * of the virtual address range was not mapped, and ENOMEM is returned if
5707  * there was insufficient memory available to complete the change.
5708  */
5709 static int
__CONCAT(PMTYPE,change_attr)5710 __CONCAT(PMTYPE, change_attr)(vm_offset_t va, vm_size_t size, int mode)
5711 {
5712 	vm_offset_t base, offset, tmpva;
5713 	pd_entry_t *pde;
5714 	pt_entry_t *pte;
5715 	int cache_bits_pte, cache_bits_pde;
5716 	bool changed;
5717 
5718 	base = trunc_page(va);
5719 	offset = va & PAGE_MASK;
5720 	size = round_page(offset + size);
5721 
5722 	/*
5723 	 * Only supported on kernel virtual addresses above the recursive map.
5724 	 */
5725 	if (base < VM_MIN_KERNEL_ADDRESS)
5726 		return (EINVAL);
5727 
5728 	cache_bits_pde = pmap_cache_bits(kernel_pmap, mode, true);
5729 	cache_bits_pte = pmap_cache_bits(kernel_pmap, mode, false);
5730 	changed = false;
5731 
5732 	/*
5733 	 * Pages that aren't mapped aren't supported.  Also break down
5734 	 * 2/4MB pages into 4KB pages if required.
5735 	 */
5736 	PMAP_LOCK(kernel_pmap);
5737 	for (tmpva = base; tmpva < base + size; ) {
5738 		pde = pmap_pde(kernel_pmap, tmpva);
5739 		if (*pde == 0) {
5740 			PMAP_UNLOCK(kernel_pmap);
5741 			return (EINVAL);
5742 		}
5743 		if (*pde & PG_PS) {
5744 			/*
5745 			 * If the current 2/4MB page already has
5746 			 * the required memory type, then we need not
5747 			 * demote this page.  Just increment tmpva to
5748 			 * the next 2/4MB page frame.
5749 			 */
5750 			if ((*pde & PG_PDE_CACHE) == cache_bits_pde) {
5751 				tmpva = trunc_4mpage(tmpva) + NBPDR;
5752 				continue;
5753 			}
5754 
5755 			/*
5756 			 * If the current offset aligns with a 2/4MB
5757 			 * page frame and there is at least 2/4MB left
5758 			 * within the range, then we need not break
5759 			 * down this page into 4KB pages.
5760 			 */
5761 			if ((tmpva & PDRMASK) == 0 &&
5762 			    tmpva + PDRMASK < base + size) {
5763 				tmpva += NBPDR;
5764 				continue;
5765 			}
5766 			if (!pmap_demote_pde(kernel_pmap, pde, tmpva)) {
5767 				PMAP_UNLOCK(kernel_pmap);
5768 				return (ENOMEM);
5769 			}
5770 		}
5771 		pte = vtopte(tmpva);
5772 		if (*pte == 0) {
5773 			PMAP_UNLOCK(kernel_pmap);
5774 			return (EINVAL);
5775 		}
5776 		tmpva += PAGE_SIZE;
5777 	}
5778 	PMAP_UNLOCK(kernel_pmap);
5779 
5780 	/*
5781 	 * Ok, all the pages exist, so run through them updating their
5782 	 * cache mode if required.
5783 	 */
5784 	for (tmpva = base; tmpva < base + size; ) {
5785 		pde = pmap_pde(kernel_pmap, tmpva);
5786 		if (*pde & PG_PS) {
5787 			if ((*pde & PG_PDE_CACHE) != cache_bits_pde) {
5788 				pmap_pde_attr(pde, cache_bits_pde);
5789 				changed = true;
5790 			}
5791 			tmpva = trunc_4mpage(tmpva) + NBPDR;
5792 		} else {
5793 			pte = vtopte(tmpva);
5794 			if ((*pte & PG_PTE_CACHE) != cache_bits_pte) {
5795 				pmap_pte_attr(pte, cache_bits_pte);
5796 				changed = true;
5797 			}
5798 			tmpva += PAGE_SIZE;
5799 		}
5800 	}
5801 
5802 	/*
5803 	 * Flush CPU caches to make sure any data isn't cached that
5804 	 * shouldn't be, etc.
5805 	 */
5806 	if (changed) {
5807 		pmap_invalidate_range_int(kernel_pmap, base, tmpva);
5808 		pmap_invalidate_cache_range(base, tmpva);
5809 	}
5810 	return (0);
5811 }
5812 
5813 /*
5814  * Perform the pmap work for mincore(2).  If the page is not both referenced and
5815  * modified by this pmap, returns its physical address so that the caller can
5816  * find other mappings.
5817  */
5818 static int
__CONCAT(PMTYPE,mincore)5819 __CONCAT(PMTYPE, mincore)(pmap_t pmap, vm_offset_t addr, vm_paddr_t *pap)
5820 {
5821 	pd_entry_t pde;
5822 	pt_entry_t pte;
5823 	vm_paddr_t pa;
5824 	int val;
5825 
5826 	PMAP_LOCK(pmap);
5827 	pde = *pmap_pde(pmap, addr);
5828 	if (pde != 0) {
5829 		if ((pde & PG_PS) != 0) {
5830 			pte = pde;
5831 			/* Compute the physical address of the 4KB page. */
5832 			pa = ((pde & PG_PS_FRAME) | (addr & PDRMASK)) &
5833 			    PG_FRAME;
5834 			val = MINCORE_PSIND(1);
5835 		} else {
5836 			pte = pmap_pte_ufast(pmap, addr, pde);
5837 			pa = pte & PG_FRAME;
5838 			val = 0;
5839 		}
5840 	} else {
5841 		pte = 0;
5842 		pa = 0;
5843 		val = 0;
5844 	}
5845 	if ((pte & PG_V) != 0) {
5846 		val |= MINCORE_INCORE;
5847 		if ((pte & (PG_M | PG_RW)) == (PG_M | PG_RW))
5848 			val |= MINCORE_MODIFIED | MINCORE_MODIFIED_OTHER;
5849 		if ((pte & PG_A) != 0)
5850 			val |= MINCORE_REFERENCED | MINCORE_REFERENCED_OTHER;
5851 	}
5852 	if ((val & (MINCORE_MODIFIED_OTHER | MINCORE_REFERENCED_OTHER)) !=
5853 	    (MINCORE_MODIFIED_OTHER | MINCORE_REFERENCED_OTHER) &&
5854 	    (pte & (PG_MANAGED | PG_V)) == (PG_MANAGED | PG_V)) {
5855 		*pap = pa;
5856 	}
5857 	PMAP_UNLOCK(pmap);
5858 	return (val);
5859 }
5860 
5861 static void
__CONCAT(PMTYPE,activate)5862 __CONCAT(PMTYPE, activate)(struct thread *td)
5863 {
5864 	pmap_t	pmap, oldpmap;
5865 	u_int	cpuid;
5866 	u_int32_t  cr3;
5867 
5868 	critical_enter();
5869 	pmap = vmspace_pmap(td->td_proc->p_vmspace);
5870 	oldpmap = PCPU_GET(curpmap);
5871 	cpuid = PCPU_GET(cpuid);
5872 #if defined(SMP)
5873 	CPU_CLR_ATOMIC(cpuid, &oldpmap->pm_active);
5874 	CPU_SET_ATOMIC(cpuid, &pmap->pm_active);
5875 #else
5876 	CPU_CLR(cpuid, &oldpmap->pm_active);
5877 	CPU_SET(cpuid, &pmap->pm_active);
5878 #endif
5879 #ifdef PMAP_PAE_COMP
5880 	cr3 = vtophys(pmap->pm_pdpt);
5881 #else
5882 	cr3 = vtophys(pmap->pm_pdir);
5883 #endif
5884 	/*
5885 	 * pmap_activate is for the current thread on the current cpu
5886 	 */
5887 	td->td_pcb->pcb_cr3 = cr3;
5888 	PCPU_SET(curpmap, pmap);
5889 	critical_exit();
5890 }
5891 
5892 static void
__CONCAT(PMTYPE,activate_boot)5893 __CONCAT(PMTYPE, activate_boot)(pmap_t pmap)
5894 {
5895 	u_int cpuid;
5896 
5897 	cpuid = PCPU_GET(cpuid);
5898 #if defined(SMP)
5899 	CPU_SET_ATOMIC(cpuid, &pmap->pm_active);
5900 #else
5901 	CPU_SET(cpuid, &pmap->pm_active);
5902 #endif
5903 	PCPU_SET(curpmap, pmap);
5904 }
5905 
5906 /*
5907  *	Increase the starting virtual address of the given mapping if a
5908  *	different alignment might result in more superpage mappings.
5909  */
5910 static void
__CONCAT(PMTYPE,align_superpage)5911 __CONCAT(PMTYPE, align_superpage)(vm_object_t object, vm_ooffset_t offset,
5912     vm_offset_t *addr, vm_size_t size)
5913 {
5914 	vm_offset_t superpage_offset;
5915 
5916 	if (size < NBPDR)
5917 		return;
5918 	if (object != NULL && (object->flags & OBJ_COLORED) != 0)
5919 		offset += ptoa(object->pg_color);
5920 	superpage_offset = offset & PDRMASK;
5921 	if (size - ((NBPDR - superpage_offset) & PDRMASK) < NBPDR ||
5922 	    (*addr & PDRMASK) == superpage_offset)
5923 		return;
5924 	if ((*addr & PDRMASK) < superpage_offset)
5925 		*addr = (*addr & ~PDRMASK) + superpage_offset;
5926 	else
5927 		*addr = ((*addr + PDRMASK) & ~PDRMASK) + superpage_offset;
5928 }
5929 
5930 static vm_offset_t
__CONCAT(PMTYPE,quick_enter_page)5931 __CONCAT(PMTYPE, quick_enter_page)(vm_page_t m)
5932 {
5933 	vm_offset_t qaddr;
5934 	pt_entry_t *pte;
5935 
5936 	critical_enter();
5937 	qaddr = PCPU_GET(qmap_addr);
5938 	pte = vtopte(qaddr);
5939 
5940 	KASSERT(*pte == 0,
5941 	    ("pmap_quick_enter_page: PTE busy %#jx", (uintmax_t)*pte));
5942 	*pte = PG_V | PG_RW | VM_PAGE_TO_PHYS(m) | PG_A | PG_M |
5943 	    pmap_cache_bits(kernel_pmap, pmap_page_get_memattr(m), false);
5944 	invlpg(qaddr);
5945 
5946 	return (qaddr);
5947 }
5948 
5949 static void
__CONCAT(PMTYPE,quick_remove_page)5950 __CONCAT(PMTYPE, quick_remove_page)(vm_offset_t addr)
5951 {
5952 	vm_offset_t qaddr;
5953 	pt_entry_t *pte;
5954 
5955 	qaddr = PCPU_GET(qmap_addr);
5956 	pte = vtopte(qaddr);
5957 
5958 	KASSERT(*pte != 0, ("pmap_quick_remove_page: PTE not in use"));
5959 	KASSERT(addr == qaddr, ("pmap_quick_remove_page: invalid address"));
5960 
5961 	*pte = 0;
5962 	critical_exit();
5963 }
5964 
5965 static vmem_t *pmap_trm_arena;
5966 static vmem_addr_t pmap_trm_arena_last = PMAP_TRM_MIN_ADDRESS;
5967 static int trm_guard = PAGE_SIZE;
5968 
5969 static int
pmap_trm_import(void * unused __unused,vmem_size_t size,int flags,vmem_addr_t * addrp)5970 pmap_trm_import(void *unused __unused, vmem_size_t size, int flags,
5971     vmem_addr_t *addrp)
5972 {
5973 	vm_page_t m;
5974 	vmem_addr_t af, addr, prev_addr;
5975 	pt_entry_t *trm_pte;
5976 
5977 	prev_addr = atomic_load_int(&pmap_trm_arena_last);
5978 	size = round_page(size) + trm_guard;
5979 	for (;;) {
5980 		if (prev_addr + size < prev_addr || prev_addr + size < size ||
5981 		    prev_addr + size > PMAP_TRM_MAX_ADDRESS)
5982 			return (ENOMEM);
5983 		addr = prev_addr + size;
5984 		if (atomic_fcmpset_int(&pmap_trm_arena_last, &prev_addr, addr))
5985 			break;
5986 	}
5987 	prev_addr += trm_guard;
5988 	trm_pte = PTmap + atop(prev_addr);
5989 	for (af = prev_addr; af < addr; af += PAGE_SIZE) {
5990 		m = vm_page_alloc_noobj(VM_ALLOC_WIRED | VM_ALLOC_WAITOK);
5991 		pte_store(&trm_pte[atop(af - prev_addr)], VM_PAGE_TO_PHYS(m) |
5992 		    PG_M | PG_A | PG_RW | PG_V | pgeflag |
5993 		    pmap_cache_bits(kernel_pmap, VM_MEMATTR_DEFAULT, false));
5994 	}
5995 	*addrp = prev_addr;
5996 	return (0);
5997 }
5998 
5999 void
pmap_init_trm(void)6000 pmap_init_trm(void)
6001 {
6002 	vm_page_t pd_m;
6003 
6004 	TUNABLE_INT_FETCH("machdep.trm_guard", &trm_guard);
6005 	if ((trm_guard & PAGE_MASK) != 0)
6006 		trm_guard = 0;
6007 	pmap_trm_arena = vmem_create("i386trampoline", 0, 0, 1, 0, M_WAITOK);
6008 	vmem_set_import(pmap_trm_arena, pmap_trm_import, NULL, NULL, PAGE_SIZE);
6009 	pd_m = vm_page_alloc_noobj(VM_ALLOC_WIRED | VM_ALLOC_WAITOK |
6010 	    VM_ALLOC_ZERO);
6011 	PTD[TRPTDI] = VM_PAGE_TO_PHYS(pd_m) | PG_M | PG_A | PG_RW | PG_V |
6012 	    pmap_cache_bits(kernel_pmap, VM_MEMATTR_DEFAULT, true);
6013 }
6014 
6015 static void *
__CONCAT(PMTYPE,trm_alloc)6016 __CONCAT(PMTYPE, trm_alloc)(size_t size, int flags)
6017 {
6018 	vmem_addr_t res;
6019 	int error;
6020 
6021 	MPASS((flags & ~(M_WAITOK | M_NOWAIT | M_ZERO)) == 0);
6022 	error = vmem_xalloc(pmap_trm_arena, roundup2(size, 4), sizeof(int),
6023 	    0, 0, VMEM_ADDR_MIN, VMEM_ADDR_MAX, flags | M_FIRSTFIT, &res);
6024 	if (error != 0)
6025 		return (NULL);
6026 	if ((flags & M_ZERO) != 0)
6027 		bzero((void *)res, size);
6028 	return ((void *)res);
6029 }
6030 
6031 static void
__CONCAT(PMTYPE,trm_free)6032 __CONCAT(PMTYPE, trm_free)(void *addr, size_t size)
6033 {
6034 
6035 	vmem_free(pmap_trm_arena, (uintptr_t)addr, roundup2(size, 4));
6036 }
6037 
6038 static void
__CONCAT(PMTYPE,ksetrw)6039 __CONCAT(PMTYPE, ksetrw)(vm_offset_t va)
6040 {
6041 
6042 	*vtopte(va) |= PG_RW;
6043 }
6044 
6045 static void
__CONCAT(PMTYPE,remap_lowptdi)6046 __CONCAT(PMTYPE, remap_lowptdi)(bool enable)
6047 {
6048 
6049 	PTD[KPTDI] = enable ? PTD[LOWPTDI] : 0;
6050 	invltlb_glob();
6051 }
6052 
6053 static vm_offset_t
__CONCAT(PMTYPE,get_map_low)6054 __CONCAT(PMTYPE, get_map_low)(void)
6055 {
6056 
6057 	return (PMAP_MAP_LOW);
6058 }
6059 
6060 static vm_offset_t
__CONCAT(PMTYPE,get_vm_maxuser_address)6061 __CONCAT(PMTYPE, get_vm_maxuser_address)(void)
6062 {
6063 
6064 	return (VM_MAXUSER_ADDRESS);
6065 }
6066 
6067 static vm_paddr_t
__CONCAT(PMTYPE,pg_frame)6068 __CONCAT(PMTYPE, pg_frame)(vm_paddr_t pa)
6069 {
6070 
6071 	return (pa & PG_FRAME);
6072 }
6073 
6074 static void
__CONCAT(PMTYPE,sf_buf_map)6075 __CONCAT(PMTYPE, sf_buf_map)(struct sf_buf *sf)
6076 {
6077 	pt_entry_t opte, *ptep;
6078 
6079 	/*
6080 	 * Update the sf_buf's virtual-to-physical mapping, flushing the
6081 	 * virtual address from the TLB.  Since the reference count for
6082 	 * the sf_buf's old mapping was zero, that mapping is not
6083 	 * currently in use.  Consequently, there is no need to exchange
6084 	 * the old and new PTEs atomically, even under PAE.
6085 	 */
6086 	ptep = vtopte(sf->kva);
6087 	opte = *ptep;
6088 	*ptep = VM_PAGE_TO_PHYS(sf->m) | PG_RW | PG_V |
6089 	    pmap_cache_bits(kernel_pmap, sf->m->md.pat_mode, false);
6090 
6091 	/*
6092 	 * Avoid unnecessary TLB invalidations: If the sf_buf's old
6093 	 * virtual-to-physical mapping was not used, then any processor
6094 	 * that has invalidated the sf_buf's virtual address from its TLB
6095 	 * since the last used mapping need not invalidate again.
6096 	 */
6097 #ifdef SMP
6098 	if ((opte & (PG_V | PG_A)) ==  (PG_V | PG_A))
6099 		CPU_ZERO(&sf->cpumask);
6100 #else
6101 	if ((opte & (PG_V | PG_A)) ==  (PG_V | PG_A))
6102 		pmap_invalidate_page_int(kernel_pmap, sf->kva);
6103 #endif
6104 }
6105 
6106 static void
__CONCAT(PMTYPE,cp_slow0_map)6107 __CONCAT(PMTYPE, cp_slow0_map)(vm_offset_t kaddr, int plen, vm_page_t *ma)
6108 {
6109 	pt_entry_t *pte;
6110 	int i;
6111 
6112 	for (i = 0, pte = vtopte(kaddr); i < plen; i++, pte++) {
6113 		*pte = PG_V | PG_RW | PG_A | PG_M | VM_PAGE_TO_PHYS(ma[i]) |
6114 		    pmap_cache_bits(kernel_pmap, pmap_page_get_memattr(ma[i]),
6115 		    false);
6116 		invlpg(kaddr + ptoa(i));
6117 	}
6118 }
6119 
6120 static u_int
__CONCAT(PMTYPE,get_kcr3)6121 __CONCAT(PMTYPE, get_kcr3)(void)
6122 {
6123 
6124 #ifdef PMAP_PAE_COMP
6125 	return ((u_int)IdlePDPT);
6126 #else
6127 	return ((u_int)IdlePTD);
6128 #endif
6129 }
6130 
6131 static u_int
__CONCAT(PMTYPE,get_cr3)6132 __CONCAT(PMTYPE, get_cr3)(pmap_t pmap)
6133 {
6134 
6135 #ifdef PMAP_PAE_COMP
6136 	return ((u_int)vtophys(pmap->pm_pdpt));
6137 #else
6138 	return ((u_int)vtophys(pmap->pm_pdir));
6139 #endif
6140 }
6141 
6142 static caddr_t
__CONCAT(PMTYPE,cmap3)6143 __CONCAT(PMTYPE, cmap3)(vm_paddr_t pa, u_int pte_bits)
6144 {
6145 	pt_entry_t *pte;
6146 
6147 	pte = CMAP3;
6148 	*pte = pa | pte_bits;
6149 	invltlb();
6150 	return (CADDR3);
6151 }
6152 
6153 static void
__CONCAT(PMTYPE,basemem_setup)6154 __CONCAT(PMTYPE, basemem_setup)(u_int basemem)
6155 {
6156 	pt_entry_t *pte;
6157 	int i;
6158 
6159 	/*
6160 	 * Map pages between basemem and ISA_HOLE_START, if any, r/w into
6161 	 * the vm86 page table so that vm86 can scribble on them using
6162 	 * the vm86 map too.  XXX: why 2 ways for this and only 1 way for
6163 	 * page 0, at least as initialized here?
6164 	 */
6165 	pte = (pt_entry_t *)vm86paddr;
6166 	for (i = basemem / 4; i < 160; i++)
6167 		pte[i] = (i << PAGE_SHIFT) | PG_V | PG_RW | PG_U;
6168 }
6169 
6170 struct bios16_pmap_handle {
6171 	pt_entry_t	*pte;
6172 	pd_entry_t	*ptd;
6173 	pt_entry_t	orig_ptd;
6174 };
6175 
6176 static void *
__CONCAT(PMTYPE,bios16_enter)6177 __CONCAT(PMTYPE, bios16_enter)(void)
6178 {
6179 	struct bios16_pmap_handle *h;
6180 
6181 	/*
6182 	 * no page table, so create one and install it.
6183 	 */
6184 	h = malloc(sizeof(struct bios16_pmap_handle), M_TEMP, M_WAITOK);
6185 	h->pte = (pt_entry_t *)malloc(PAGE_SIZE, M_TEMP, M_WAITOK);
6186 	h->ptd = IdlePTD;
6187 	*h->pte = vm86phystk | PG_RW | PG_V;
6188 	h->orig_ptd = *h->ptd;
6189 	*h->ptd = vtophys(h->pte) | PG_RW | PG_V;
6190 	pmap_invalidate_all_int(kernel_pmap);	/* XXX insurance for now */
6191 	return (h);
6192 }
6193 
6194 static void
__CONCAT(PMTYPE,bios16_leave)6195 __CONCAT(PMTYPE, bios16_leave)(void *arg)
6196 {
6197 	struct bios16_pmap_handle *h;
6198 
6199 	h = arg;
6200 	*h->ptd = h->orig_ptd;		/* remove page table */
6201 	/*
6202 	 * XXX only needs to be invlpg(0) but that doesn't work on the 386
6203 	 */
6204 	pmap_invalidate_all_int(kernel_pmap);
6205 	free(h->pte, M_TEMP);		/* ... and free it */
6206 }
6207 
6208 struct pmap_kernel_map_range {
6209 	vm_offset_t sva;
6210 	pt_entry_t attrs;
6211 	int ptes;
6212 	int pdes;
6213 	int pdpes;
6214 };
6215 
6216 static void
sysctl_kmaps_dump(struct sbuf * sb,struct pmap_kernel_map_range * range,vm_offset_t eva)6217 sysctl_kmaps_dump(struct sbuf *sb, struct pmap_kernel_map_range *range,
6218     vm_offset_t eva)
6219 {
6220 	const char *mode;
6221 	int i, pat_idx;
6222 
6223 	if (eva <= range->sva)
6224 		return;
6225 
6226 	pat_idx = pmap_pat_index(kernel_pmap, range->attrs, true);
6227 	for (i = 0; i < PAT_INDEX_SIZE; i++)
6228 		if (pat_index[i] == pat_idx)
6229 			break;
6230 
6231 	switch (i) {
6232 	case PAT_WRITE_BACK:
6233 		mode = "WB";
6234 		break;
6235 	case PAT_WRITE_THROUGH:
6236 		mode = "WT";
6237 		break;
6238 	case PAT_UNCACHEABLE:
6239 		mode = "UC";
6240 		break;
6241 	case PAT_UNCACHED:
6242 		mode = "U-";
6243 		break;
6244 	case PAT_WRITE_PROTECTED:
6245 		mode = "WP";
6246 		break;
6247 	case PAT_WRITE_COMBINING:
6248 		mode = "WC";
6249 		break;
6250 	default:
6251 		printf("%s: unknown PAT mode %#x for range 0x%08x-0x%08x\n",
6252 		    __func__, pat_idx, range->sva, eva);
6253 		mode = "??";
6254 		break;
6255 	}
6256 
6257 	sbuf_printf(sb, "0x%08x-0x%08x r%c%c%c%c %s %d %d %d\n",
6258 	    range->sva, eva,
6259 	    (range->attrs & PG_RW) != 0 ? 'w' : '-',
6260 	    (range->attrs & pg_nx) != 0 ? '-' : 'x',
6261 	    (range->attrs & PG_U) != 0 ? 'u' : 's',
6262 	    (range->attrs & PG_G) != 0 ? 'g' : '-',
6263 	    mode, range->pdpes, range->pdes, range->ptes);
6264 
6265 	/* Reset to sentinel value. */
6266 	range->sva = 0xffffffff;
6267 }
6268 
6269 /*
6270  * Determine whether the attributes specified by a page table entry match those
6271  * being tracked by the current range.  This is not quite as simple as a direct
6272  * flag comparison since some PAT modes have multiple representations.
6273  */
6274 static bool
sysctl_kmaps_match(struct pmap_kernel_map_range * range,pt_entry_t attrs)6275 sysctl_kmaps_match(struct pmap_kernel_map_range *range, pt_entry_t attrs)
6276 {
6277 	pt_entry_t diff, mask;
6278 
6279 	mask = pg_nx | PG_G | PG_RW | PG_U | PG_PDE_CACHE;
6280 	diff = (range->attrs ^ attrs) & mask;
6281 	if (diff == 0)
6282 		return (true);
6283 	if ((diff & ~PG_PDE_PAT) == 0 &&
6284 	    pmap_pat_index(kernel_pmap, range->attrs, true) ==
6285 	    pmap_pat_index(kernel_pmap, attrs, true))
6286 		return (true);
6287 	return (false);
6288 }
6289 
6290 static void
sysctl_kmaps_reinit(struct pmap_kernel_map_range * range,vm_offset_t va,pt_entry_t attrs)6291 sysctl_kmaps_reinit(struct pmap_kernel_map_range *range, vm_offset_t va,
6292     pt_entry_t attrs)
6293 {
6294 
6295 	memset(range, 0, sizeof(*range));
6296 	range->sva = va;
6297 	range->attrs = attrs;
6298 }
6299 
6300 /*
6301  * Given a leaf PTE, derive the mapping's attributes.  If they do not match
6302  * those of the current run, dump the address range and its attributes, and
6303  * begin a new run.
6304  */
6305 static void
sysctl_kmaps_check(struct sbuf * sb,struct pmap_kernel_map_range * range,vm_offset_t va,pd_entry_t pde,pt_entry_t pte)6306 sysctl_kmaps_check(struct sbuf *sb, struct pmap_kernel_map_range *range,
6307     vm_offset_t va, pd_entry_t pde, pt_entry_t pte)
6308 {
6309 	pt_entry_t attrs;
6310 
6311 	attrs = pde & (PG_RW | PG_U | pg_nx);
6312 
6313 	if ((pde & PG_PS) != 0) {
6314 		attrs |= pde & (PG_G | PG_PDE_CACHE);
6315 	} else if (pte != 0) {
6316 		attrs |= pte & pg_nx;
6317 		attrs &= pg_nx | (pte & (PG_RW | PG_U));
6318 		attrs |= pte & (PG_G | PG_PTE_CACHE);
6319 
6320 		/* Canonicalize by always using the PDE PAT bit. */
6321 		if ((attrs & PG_PTE_PAT) != 0)
6322 			attrs ^= PG_PDE_PAT | PG_PTE_PAT;
6323 	}
6324 
6325 	if (range->sva > va || !sysctl_kmaps_match(range, attrs)) {
6326 		sysctl_kmaps_dump(sb, range, va);
6327 		sysctl_kmaps_reinit(range, va, attrs);
6328 	}
6329 }
6330 
6331 static int
__CONCAT(PMTYPE,sysctl_kmaps)6332 __CONCAT(PMTYPE, sysctl_kmaps)(SYSCTL_HANDLER_ARGS)
6333 {
6334 	struct pmap_kernel_map_range range;
6335 	struct sbuf sbuf, *sb;
6336 	pd_entry_t pde;
6337 	pt_entry_t *pt, pte;
6338 	vm_offset_t sva;
6339 	int error;
6340 	u_int i, k;
6341 
6342 	error = sysctl_wire_old_buffer(req, 0);
6343 	if (error != 0)
6344 		return (error);
6345 	sb = &sbuf;
6346 	sbuf_new_for_sysctl(sb, NULL, PAGE_SIZE, req);
6347 
6348 	/* Sentinel value. */
6349 	range.sva = 0xffffffff;
6350 
6351 	/*
6352 	 * Iterate over the kernel page tables without holding the
6353 	 * kernel pmap lock.  Kernel page table pages are never freed,
6354 	 * so at worst we will observe inconsistencies in the output.
6355 	 */
6356 	for (sva = 0, i = 0; i < NPTEPG * NPGPTD * NPDEPG ;) {
6357 		if (i == 0)
6358 			sbuf_printf(sb, "\nLow PDE:\n");
6359 		else if (i == LOWPTDI * NPTEPG)
6360 			sbuf_printf(sb, "Low PDE dup:\n");
6361 		else if (i == PTDPTDI * NPTEPG)
6362 			sbuf_printf(sb, "Recursive map:\n");
6363 		else if (i == KERNPTDI * NPTEPG)
6364 			sbuf_printf(sb, "Kernel base:\n");
6365 		else if (i == TRPTDI * NPTEPG)
6366 			sbuf_printf(sb, "Trampoline:\n");
6367 		pde = IdlePTD[sva >> PDRSHIFT];
6368 		if ((pde & PG_V) == 0) {
6369 			sva = rounddown2(sva, NBPDR);
6370 			sysctl_kmaps_dump(sb, &range, sva);
6371 			sva += NBPDR;
6372 			i += NPTEPG;
6373 			continue;
6374 		}
6375 		if ((pde & PG_PS) != 0) {
6376 			sysctl_kmaps_check(sb, &range, sva, pde, 0);
6377 			range.pdes++;
6378 			sva += NBPDR;
6379 			i += NPTEPG;
6380 			continue;
6381 		}
6382 		for (pt = vtopte(sva), k = 0; k < NPTEPG; i++, k++, pt++,
6383 		    sva += PAGE_SIZE) {
6384 			pte = *pt;
6385 			if ((pte & PG_V) == 0) {
6386 				sysctl_kmaps_dump(sb, &range, sva);
6387 				continue;
6388 			}
6389 			sysctl_kmaps_check(sb, &range, sva, pde, pte);
6390 			range.ptes++;
6391 		}
6392 	}
6393 
6394 	error = sbuf_finish(sb);
6395 	sbuf_delete(sb);
6396 	return (error);
6397 }
6398 
6399 #define	PMM(a)					\
6400 	.pm_##a = __CONCAT(PMTYPE, a),
6401 
6402 struct pmap_methods __CONCAT(PMTYPE, methods) = {
6403 	PMM(ksetrw)
6404 	PMM(remap_lower)
6405 	PMM(remap_lowptdi)
6406 	PMM(align_superpage)
6407 	PMM(quick_enter_page)
6408 	PMM(quick_remove_page)
6409 	PMM(trm_alloc)
6410 	PMM(trm_free)
6411 	PMM(get_map_low)
6412 	PMM(get_vm_maxuser_address)
6413 	PMM(kextract)
6414 	PMM(pg_frame)
6415 	PMM(sf_buf_map)
6416 	PMM(cp_slow0_map)
6417 	PMM(get_kcr3)
6418 	PMM(get_cr3)
6419 	PMM(cmap3)
6420 	PMM(basemem_setup)
6421 	PMM(set_nx)
6422 	PMM(bios16_enter)
6423 	PMM(bios16_leave)
6424 	PMM(bootstrap)
6425 	PMM(is_valid_memattr)
6426 	PMM(cache_bits)
6427 	PMM(ps_enabled)
6428 	PMM(pinit0)
6429 	PMM(pinit)
6430 	PMM(activate)
6431 	PMM(activate_boot)
6432 	PMM(advise)
6433 	PMM(clear_modify)
6434 	PMM(change_attr)
6435 	PMM(mincore)
6436 	PMM(copy)
6437 	PMM(copy_page)
6438 	PMM(copy_pages)
6439 	PMM(zero_page)
6440 	PMM(zero_page_area)
6441 	PMM(enter)
6442 	PMM(enter_object)
6443 	PMM(enter_quick)
6444 	PMM(kenter_temporary)
6445 	PMM(object_init_pt)
6446 	PMM(unwire)
6447 	PMM(page_exists_quick)
6448 	PMM(page_wired_mappings)
6449 	PMM(page_is_mapped)
6450 	PMM(remove_pages)
6451 	PMM(is_modified)
6452 	PMM(is_prefaultable)
6453 	PMM(is_referenced)
6454 	PMM(remove_write)
6455 	PMM(ts_referenced)
6456 	PMM(mapdev_attr)
6457 	PMM(unmapdev)
6458 	PMM(page_set_memattr)
6459 	PMM(extract)
6460 	PMM(extract_and_hold)
6461 	PMM(map)
6462 	PMM(qenter)
6463 	PMM(qremove)
6464 	PMM(release)
6465 	PMM(remove)
6466 	PMM(protect)
6467 	PMM(remove_all)
6468 	PMM(init)
6469 	PMM(init_pat)
6470 	PMM(growkernel)
6471 	PMM(invalidate_page)
6472 	PMM(invalidate_range)
6473 	PMM(invalidate_all)
6474 	PMM(invalidate_cache)
6475 	PMM(flush_page)
6476 	PMM(kenter)
6477 	PMM(kremove)
6478 	PMM(sysctl_kmaps)
6479 };
6480