Although defined in sys/time.h we don't have CLOCK_VIRTUAL and CLOCK_PROF
[dragonfly.git] / sys / vm / vm_map.c
CommitLineData
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1/*
2 * Copyright (c) 1991, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * The Mach Operating System project at Carnegie-Mellon University.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by the University of
19 * California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 *
36 * from: @(#)vm_map.c 8.3 (Berkeley) 1/12/94
37 *
38 *
39 * Copyright (c) 1987, 1990 Carnegie-Mellon University.
40 * All rights reserved.
41 *
42 * Authors: Avadis Tevanian, Jr., Michael Wayne Young
43 *
44 * Permission to use, copy, modify and distribute this software and
45 * its documentation is hereby granted, provided that both the copyright
46 * notice and this permission notice appear in all copies of the
47 * software, derivative works or modified versions, and any portions
48 * thereof, and that both notices appear in supporting documentation.
49 *
50 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
51 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
52 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
53 *
54 * Carnegie Mellon requests users of this software to return to
55 *
56 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
57 * School of Computer Science
58 * Carnegie Mellon University
59 * Pittsburgh PA 15213-3890
60 *
61 * any improvements or extensions that they make and grant Carnegie the
62 * rights to redistribute these changes.
63 *
64 * $FreeBSD: src/sys/vm/vm_map.c,v 1.187.2.19 2003/05/27 00:47:02 alc Exp $
135d7199 65 * $DragonFly: src/sys/vm/vm_map.c,v 1.55 2007/01/07 08:37:37 dillon Exp $
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66 */
67
68/*
69 * Virtual memory mapping module.
70 */
71
72#include <sys/param.h>
73#include <sys/systm.h>
74#include <sys/proc.h>
fef0fdf2 75#include <sys/lock.h>
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76#include <sys/vmmeter.h>
77#include <sys/mman.h>
78#include <sys/vnode.h>
79#include <sys/resourcevar.h>
fef0fdf2 80#include <sys/shm.h>
686dbf64 81#include <sys/tree.h>
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82
83#include <vm/vm.h>
84#include <vm/vm_param.h>
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85#include <vm/pmap.h>
86#include <vm/vm_map.h>
87#include <vm/vm_page.h>
88#include <vm/vm_object.h>
89#include <vm/vm_pager.h>
90#include <vm/vm_kern.h>
91#include <vm/vm_extern.h>
92#include <vm/swap_pager.h>
93#include <vm/vm_zone.h>
94
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95#include <sys/thread2.h>
96
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97/*
98 * Virtual memory maps provide for the mapping, protection,
99 * and sharing of virtual memory objects. In addition,
100 * this module provides for an efficient virtual copy of
101 * memory from one map to another.
102 *
103 * Synchronization is required prior to most operations.
104 *
105 * Maps consist of an ordered doubly-linked list of simple
106 * entries; a single hint is used to speed up lookups.
107 *
108 * Since portions of maps are specified by start/end addresses,
109 * which may not align with existing map entries, all
110 * routines merely "clip" entries to these start/end values.
111 * [That is, an entry is split into two, bordering at a
112 * start or end value.] Note that these clippings may not
113 * always be necessary (as the two resulting entries are then
114 * not changed); however, the clipping is done for convenience.
115 *
116 * As mentioned above, virtual copy operations are performed
117 * by copying VM object references from one map to
118 * another, and then marking both regions as copy-on-write.
119 */
120
121/*
122 * vm_map_startup:
123 *
124 * Initialize the vm_map module. Must be called before
125 * any other vm_map routines.
126 *
127 * Map and entry structures are allocated from the general
128 * purpose memory pool with some exceptions:
129 *
130 * - The kernel map and kmem submap are allocated statically.
131 * - Kernel map entries are allocated out of a static pool.
132 *
133 * These restrictions are necessary since malloc() uses the
134 * maps and requires map entries.
135 */
136
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137#define VMEPERCPU 2
138
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139static struct vm_zone mapentzone_store, mapzone_store;
140static vm_zone_t mapentzone, mapzone, vmspace_zone;
141static struct vm_object mapentobj, mapobj;
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142
143static struct vm_map_entry map_entry_init[MAX_MAPENT];
c4ae567f 144static struct vm_map_entry cpu_map_entry_init[MAXCPU][VMEPERCPU];
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145static struct vm_map map_init[MAX_KMAP];
146
53025830 147static void vm_map_entry_shadow(vm_map_entry_t entry);
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148static vm_map_entry_t vm_map_entry_create(vm_map_t map, int *);
149static void vm_map_entry_dispose (vm_map_t map, vm_map_entry_t entry, int *);
150static void _vm_map_clip_end (vm_map_t, vm_map_entry_t, vm_offset_t, int *);
151static void _vm_map_clip_start (vm_map_t, vm_map_entry_t, vm_offset_t, int *);
152static void vm_map_entry_delete (vm_map_t, vm_map_entry_t, int *);
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153static void vm_map_entry_unwire (vm_map_t, vm_map_entry_t);
154static void vm_map_copy_entry (vm_map_t, vm_map_t, vm_map_entry_t,
155 vm_map_entry_t);
156static void vm_map_split (vm_map_entry_t);
a108bf71 157static void vm_map_unclip_range (vm_map_t map, vm_map_entry_t start_entry, vm_offset_t start, vm_offset_t end, int *count, int flags);
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158
159void
57e43348 160vm_map_startup(void)
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161{
162 mapzone = &mapzone_store;
163 zbootinit(mapzone, "MAP", sizeof (struct vm_map),
164 map_init, MAX_KMAP);
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165 mapentzone = &mapentzone_store;
166 zbootinit(mapentzone, "MAP ENTRY", sizeof (struct vm_map_entry),
167 map_entry_init, MAX_MAPENT);
168}
169
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170/*
171 * Red black tree functions
172 */
173static int rb_vm_map_compare(vm_map_entry_t a, vm_map_entry_t b);
174RB_GENERATE(vm_map_rb_tree, vm_map_entry, rb_entry, rb_vm_map_compare);
175
176/* a->start is address, and the only field has to be initialized */
177static int
178rb_vm_map_compare(vm_map_entry_t a, vm_map_entry_t b)
179{
180 if (a->start < b->start)
181 return(-1);
182 else if (a->start > b->start)
183 return(1);
184 return(0);
185}
186
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187/*
188 * Allocate a vmspace structure, including a vm_map and pmap,
189 * and initialize those structures. The refcnt is set to 1.
190 * The remaining fields must be initialized by the caller.
191 */
192struct vmspace *
57e43348 193vmspace_alloc(vm_offset_t min, vm_offset_t max)
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194{
195 struct vmspace *vm;
196
197 vm = zalloc(vmspace_zone);
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198 bzero(&vm->vm_startcopy,
199 (char *)&vm->vm_endcopy - (char *)&vm->vm_startcopy);
e4846942 200 vm_map_init(&vm->vm_map, min, max, NULL);
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201 pmap_pinit(vmspace_pmap(vm));
202 vm->vm_map.pmap = vmspace_pmap(vm); /* XXX */
203 vm->vm_refcnt = 1;
204 vm->vm_shm = NULL;
205 vm->vm_exitingcnt = 0;
135d7199 206 cpu_vmspace_alloc(vm);
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207 return (vm);
208}
209
210void
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211vm_init2(void)
212{
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213 zinitna(mapentzone, &mapentobj, NULL, 0, 0,
214 ZONE_USE_RESERVE | ZONE_SPECIAL, 1);
a108bf71 215 zinitna(mapzone, &mapobj, NULL, 0, 0, 0, 1);
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216 vmspace_zone = zinit("VMSPACE", sizeof (struct vmspace), 0, 0, 3);
217 pmap_init2();
218 vm_object_init2();
219}
220
221static __inline void
222vmspace_dofree(struct vmspace *vm)
223{
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224 int count;
225
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226 cpu_vmspace_free(vm);
227
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228 /*
229 * Make sure any SysV shm is freed, it might not have in
230 * exit1()
231 */
232 shmexit(vm);
233
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234 KKASSERT(vm->vm_upcalls == NULL);
235
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236 /*
237 * Lock the map, to wait out all other references to it.
238 * Delete all of the mappings and pages they hold, then call
239 * the pmap module to reclaim anything left.
240 */
a108bf71 241 count = vm_map_entry_reserve(MAP_RESERVE_COUNT);
984263bc 242 vm_map_lock(&vm->vm_map);
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243 vm_map_delete(&vm->vm_map, vm->vm_map.min_offset,
244 vm->vm_map.max_offset, &count);
984263bc 245 vm_map_unlock(&vm->vm_map);
a108bf71 246 vm_map_entry_release(count);
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247
248 pmap_release(vmspace_pmap(vm));
249 zfree(vmspace_zone, vm);
250}
251
252void
253vmspace_free(struct vmspace *vm)
254{
255 if (vm->vm_refcnt == 0)
256 panic("vmspace_free: attempt to free already freed vmspace");
257
258 if (--vm->vm_refcnt == 0 && vm->vm_exitingcnt == 0)
259 vmspace_dofree(vm);
260}
261
262void
263vmspace_exitfree(struct proc *p)
264{
265 struct vmspace *vm;
266
267 vm = p->p_vmspace;
268 p->p_vmspace = NULL;
269
270 /*
271 * cleanup by parent process wait()ing on exiting child. vm_refcnt
272 * may not be 0 (e.g. fork() and child exits without exec()ing).
273 * exitingcnt may increment above 0 and drop back down to zero
274 * several times while vm_refcnt is held non-zero. vm_refcnt
275 * may also increment above 0 and drop back down to zero several
276 * times while vm_exitingcnt is held non-zero.
277 *
278 * The last wait on the exiting child's vmspace will clean up
279 * the remainder of the vmspace.
280 */
281 if (--vm->vm_exitingcnt == 0 && vm->vm_refcnt == 0)
282 vmspace_dofree(vm);
283}
284
285/*
286 * vmspace_swap_count() - count the approximate swap useage in pages for a
287 * vmspace.
288 *
289 * Swap useage is determined by taking the proportional swap used by
290 * VM objects backing the VM map. To make up for fractional losses,
291 * if the VM object has any swap use at all the associated map entries
292 * count for at least 1 swap page.
293 */
294int
295vmspace_swap_count(struct vmspace *vmspace)
296{
297 vm_map_t map = &vmspace->vm_map;
298 vm_map_entry_t cur;
1b874851 299 vm_object_t object;
984263bc 300 int count = 0;
1b874851 301 int n;
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302
303 for (cur = map->header.next; cur != &map->header; cur = cur->next) {
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304 switch(cur->maptype) {
305 case VM_MAPTYPE_NORMAL:
306 case VM_MAPTYPE_VPAGETABLE:
307 if ((object = cur->object.vm_object) == NULL)
308 break;
309 if (object->type != OBJT_SWAP)
310 break;
311 n = (cur->end - cur->start) / PAGE_SIZE;
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312 if (object->un_pager.swp.swp_bcount) {
313 count += object->un_pager.swp.swp_bcount *
314 SWAP_META_PAGES * n / object->size + 1;
315 }
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316 break;
317 default:
318 break;
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319 }
320 }
321 return(count);
322}
323
324
325/*
326 * vm_map_create:
327 *
328 * Creates and returns a new empty VM map with
329 * the given physical map structure, and having
330 * the given lower and upper address bounds.
331 */
332vm_map_t
e4846942 333vm_map_create(vm_map_t result, pmap_t pmap, vm_offset_t min, vm_offset_t max)
984263bc 334{
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335 if (result == NULL)
336 result = zalloc(mapzone);
337 vm_map_init(result, min, max, pmap);
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338 return (result);
339}
340
341/*
342 * Initialize an existing vm_map structure
343 * such as that in the vmspace structure.
344 * The pmap is set elsewhere.
345 */
346void
e4846942 347vm_map_init(struct vm_map *map, vm_offset_t min, vm_offset_t max, pmap_t pmap)
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348{
349 map->header.next = map->header.prev = &map->header;
686dbf64 350 RB_INIT(&map->rb_root);
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351 map->nentries = 0;
352 map->size = 0;
353 map->system_map = 0;
354 map->infork = 0;
355 map->min_offset = min;
356 map->max_offset = max;
e4846942 357 map->pmap = pmap;
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358 map->first_free = &map->header;
359 map->hint = &map->header;
360 map->timestamp = 0;
ab6f251b 361 lockinit(&map->lock, "thrd_sleep", 0, 0);
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362}
363
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364/*
365 * Shadow the vm_map_entry's object. This typically needs to be done when
366 * a write fault is taken on an entry which had previously been cloned by
367 * fork(). The shared object (which might be NULL) must become private so
368 * we add a shadow layer above it.
369 *
370 * Object allocation for anonymous mappings is defered as long as possible.
371 * When creating a shadow, however, the underlying object must be instantiated
372 * so it can be shared.
373 *
374 * If the map segment is governed by a virtual page table then it is
375 * possible to address offsets beyond the mapped area. Just allocate
376 * a maximally sized object for this case.
377 */
378static
379void
380vm_map_entry_shadow(vm_map_entry_t entry)
381{
382 if (entry->maptype == VM_MAPTYPE_VPAGETABLE) {
383 vm_object_shadow(&entry->object.vm_object, &entry->offset,
384 0x7FFFFFFF); /* XXX */
385 } else {
386 vm_object_shadow(&entry->object.vm_object, &entry->offset,
387 atop(entry->end - entry->start));
388 }
389 entry->eflags &= ~MAP_ENTRY_NEEDS_COPY;
390}
391
392/*
393 * Allocate an object for a vm_map_entry.
394 *
395 * Object allocation for anonymous mappings is defered as long as possible.
396 * This function is called when we can defer no longer, generally when a map
397 * entry might be split or forked or takes a page fault.
398 *
399 * If the map segment is governed by a virtual page table then it is
400 * possible to address offsets beyond the mapped area. Just allocate
401 * a maximally sized object for this case.
402 */
403void
404vm_map_entry_allocate_object(vm_map_entry_t entry)
405{
406 vm_object_t obj;
407
408 if (entry->maptype == VM_MAPTYPE_VPAGETABLE) {
409 obj = vm_object_allocate(OBJT_DEFAULT, 0x7FFFFFFF); /* XXX */
410 } else {
411 obj = vm_object_allocate(OBJT_DEFAULT,
412 atop(entry->end - entry->start));
413 }
414 entry->object.vm_object = obj;
415 entry->offset = 0;
416}
417
41a01a4d 418/*
c4ae567f 419 * vm_map_entry_reserve_cpu_init:
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420 *
421 * Set an initial negative count so the first attempt to reserve
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422 * space preloads a bunch of vm_map_entry's for this cpu. Also
423 * pre-allocate 2 vm_map_entries which will be needed by zalloc() to
424 * map a new page for vm_map_entry structures. SMP systems are
425 * particularly sensitive.
426 *
427 * This routine is called in early boot so we cannot just call
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428 * vm_map_entry_reserve().
429 *
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430 * May be called for a gd other then mycpu, but may only be called
431 * during early boot.
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432 */
433void
434vm_map_entry_reserve_cpu_init(globaldata_t gd)
435{
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436 vm_map_entry_t entry;
437 int i;
438
41a01a4d 439 gd->gd_vme_avail -= MAP_RESERVE_COUNT * 2;
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440 entry = &cpu_map_entry_init[gd->gd_cpuid][0];
441 for (i = 0; i < VMEPERCPU; ++i, ++entry) {
442 entry->next = gd->gd_vme_base;
443 gd->gd_vme_base = entry;
444 }
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445}
446
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447/*
448 * vm_map_entry_reserve:
449 *
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450 * Reserves vm_map_entry structures so code later on can manipulate
451 * map_entry structures within a locked map without blocking trying
452 * to allocate a new vm_map_entry.
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453 */
454int
455vm_map_entry_reserve(int count)
456{
457 struct globaldata *gd = mycpu;
458 vm_map_entry_t entry;
459
460 crit_enter();
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461
462 /*
463 * Make sure we have enough structures in gd_vme_base to handle
464 * the reservation request.
465 */
ac13eccd 466 while (gd->gd_vme_avail < count) {
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467 entry = zalloc(mapentzone);
468 entry->next = gd->gd_vme_base;
469 gd->gd_vme_base = entry;
470 ++gd->gd_vme_avail;
471 }
ac13eccd 472 gd->gd_vme_avail -= count;
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473 crit_exit();
474 return(count);
475}
476
477/*
478 * vm_map_entry_release:
479 *
480 * Releases previously reserved vm_map_entry structures that were not
481 * used. If we have too much junk in our per-cpu cache clean some of
482 * it out.
483 */
484void
485vm_map_entry_release(int count)
486{
487 struct globaldata *gd = mycpu;
488 vm_map_entry_t entry;
489
490 crit_enter();
491 gd->gd_vme_avail += count;
492 while (gd->gd_vme_avail > MAP_RESERVE_SLOP) {
493 entry = gd->gd_vme_base;
494 KKASSERT(entry != NULL);
495 gd->gd_vme_base = entry->next;
496 --gd->gd_vme_avail;
497 crit_exit();
498 zfree(mapentzone, entry);
499 crit_enter();
500 }
501 crit_exit();
502}
503
504/*
505 * vm_map_entry_kreserve:
506 *
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507 * Reserve map entry structures for use in kernel_map itself. These
508 * entries have *ALREADY* been reserved on a per-cpu basis when the map
509 * was inited. This function is used by zalloc() to avoid a recursion
510 * when zalloc() itself needs to allocate additional kernel memory.
511 *
512 * This function works like the normal reserve but does not load the
513 * vm_map_entry cache (because that would result in an infinite
514 * recursion). Note that gd_vme_avail may go negative. This is expected.
a108bf71 515 *
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516 * Any caller of this function must be sure to renormalize after
517 * potentially eating entries to ensure that the reserve supply
518 * remains intact.
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519 */
520int
521vm_map_entry_kreserve(int count)
522{
523 struct globaldata *gd = mycpu;
524
525 crit_enter();
c4ae567f 526 gd->gd_vme_avail -= count;
a108bf71 527 crit_exit();
c4ae567f 528 KASSERT(gd->gd_vme_base != NULL, ("no reserved entries left, gd_vme_avail = %d\n", gd->gd_vme_avail));
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529 return(count);
530}
531
532/*
533 * vm_map_entry_krelease:
534 *
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535 * Release previously reserved map entries for kernel_map. We do not
536 * attempt to clean up like the normal release function as this would
537 * cause an unnecessary (but probably not fatal) deep procedure call.
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538 */
539void
540vm_map_entry_krelease(int count)
541{
542 struct globaldata *gd = mycpu;
543
544 crit_enter();
c4ae567f 545 gd->gd_vme_avail += count;
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546 crit_exit();
547}
548
984263bc 549/*
8a8d5d85 550 * vm_map_entry_create: [ internal use only ]
984263bc 551 *
8a8d5d85 552 * Allocates a VM map entry for insertion. No entry fields are filled
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553 * in.
554 *
555 * This routine may be called from an interrupt thread but not a FAST
556 * interrupt. This routine may recurse the map lock.
984263bc 557 */
8a8d5d85 558static vm_map_entry_t
a108bf71 559vm_map_entry_create(vm_map_t map, int *countp)
984263bc 560{
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561 struct globaldata *gd = mycpu;
562 vm_map_entry_t entry;
8a8d5d85 563
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564 KKASSERT(*countp > 0);
565 --*countp;
566 crit_enter();
567 entry = gd->gd_vme_base;
568 KASSERT(entry != NULL, ("gd_vme_base NULL! count %d", *countp));
569 gd->gd_vme_base = entry->next;
570 crit_exit();
571 return(entry);
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572}
573
574/*
8a8d5d85 575 * vm_map_entry_dispose: [ internal use only ]
984263bc 576 *
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577 * Dispose of a vm_map_entry that is no longer being referenced. This
578 * function may be called from an interrupt.
984263bc 579 */
8a8d5d85 580static void
a108bf71 581vm_map_entry_dispose(vm_map_t map, vm_map_entry_t entry, int *countp)
984263bc 582{
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583 struct globaldata *gd = mycpu;
584
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585 KKASSERT(map->hint != entry);
586 KKASSERT(map->first_free != entry);
587
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588 ++*countp;
589 crit_enter();
590 entry->next = gd->gd_vme_base;
591 gd->gd_vme_base = entry;
592 crit_exit();
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593}
594
8a8d5d85 595
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596/*
597 * vm_map_entry_{un,}link:
598 *
599 * Insert/remove entries from maps.
600 */
601static __inline void
602vm_map_entry_link(vm_map_t map,
603 vm_map_entry_t after_where,
604 vm_map_entry_t entry)
605{
606 map->nentries++;
607 entry->prev = after_where;
608 entry->next = after_where->next;
609 entry->next->prev = entry;
610 after_where->next = entry;
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611 if (vm_map_rb_tree_RB_INSERT(&map->rb_root, entry))
612 panic("vm_map_entry_link: dup addr map %p ent %p", map, entry);
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613}
614
615static __inline void
616vm_map_entry_unlink(vm_map_t map,
617 vm_map_entry_t entry)
618{
619 vm_map_entry_t prev;
620 vm_map_entry_t next;
621
622 if (entry->eflags & MAP_ENTRY_IN_TRANSITION)
623 panic("vm_map_entry_unlink: attempt to mess with locked entry! %p", entry);
624 prev = entry->prev;
625 next = entry->next;
626 next->prev = prev;
627 prev->next = next;
686dbf64 628 vm_map_rb_tree_RB_REMOVE(&map->rb_root, entry);
984263bc
MD
629 map->nentries--;
630}
631
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632/*
633 * vm_map_lookup_entry: [ internal use only ]
634 *
635 * Finds the map entry containing (or
636 * immediately preceding) the specified address
637 * in the given map; the entry is returned
638 * in the "entry" parameter. The boolean
639 * result indicates whether the address is
640 * actually contained in the map.
641 */
642boolean_t
57e43348
MD
643vm_map_lookup_entry(vm_map_t map, vm_offset_t address,
644 vm_map_entry_t *entry /* OUT */)
984263bc 645{
686dbf64 646 vm_map_entry_t tmp;
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MD
647 vm_map_entry_t last;
648
686dbf64 649#if 0
984263bc 650 /*
686dbf64
MD
651 * XXX TEMPORARILY DISABLED. For some reason our attempt to revive
652 * the hint code with the red-black lookup meets with system crashes
653 * and lockups. We do not yet know why.
654 *
655 * It is possible that the problem is related to the setting
656 * of the hint during map_entry deletion, in the code specified
657 * at the GGG comment later on in this file.
984263bc 658 */
686dbf64
MD
659 /*
660 * Quickly check the cached hint, there's a good chance of a match.
661 */
662 if (map->hint != &map->header) {
663 tmp = map->hint;
664 if (address >= tmp->start && address < tmp->end) {
665 *entry = tmp;
666 return(TRUE);
984263bc 667 }
984263bc 668 }
686dbf64 669#endif
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MD
670
671 /*
686dbf64
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672 * Locate the record from the top of the tree. 'last' tracks the
673 * closest prior record and is returned if no match is found, which
674 * in binary tree terms means tracking the most recent right-branch
675 * taken. If there is no prior record, &map->header is returned.
984263bc 676 */
686dbf64
MD
677 last = &map->header;
678 tmp = RB_ROOT(&map->rb_root);
679
680 while (tmp) {
681 if (address >= tmp->start) {
682 if (address < tmp->end) {
683 *entry = tmp;
684 map->hint = tmp;
685 return(TRUE);
984263bc 686 }
686dbf64
MD
687 last = tmp;
688 tmp = RB_RIGHT(tmp, rb_entry);
689 } else {
690 tmp = RB_LEFT(tmp, rb_entry);
984263bc 691 }
984263bc 692 }
686dbf64 693 *entry = last;
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694 return (FALSE);
695}
696
697/*
698 * vm_map_insert:
699 *
700 * Inserts the given whole VM object into the target
701 * map at the specified address range. The object's
702 * size should match that of the address range.
703 *
a108bf71
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704 * Requires that the map be locked, and leaves it so. Requires that
705 * sufficient vm_map_entry structures have been reserved and tracks
706 * the use via countp.
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707 *
708 * If object is non-NULL, ref count must be bumped by caller
709 * prior to making call to account for the new entry.
710 */
711int
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712vm_map_insert(vm_map_t map, int *countp,
713 vm_object_t object, vm_ooffset_t offset,
1b874851
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714 vm_offset_t start, vm_offset_t end,
715 vm_maptype_t maptype,
716 vm_prot_t prot, vm_prot_t max,
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717 int cow)
718{
719 vm_map_entry_t new_entry;
720 vm_map_entry_t prev_entry;
721 vm_map_entry_t temp_entry;
722 vm_eflags_t protoeflags;
723
724 /*
725 * Check that the start and end points are not bogus.
726 */
727
728 if ((start < map->min_offset) || (end > map->max_offset) ||
729 (start >= end))
730 return (KERN_INVALID_ADDRESS);
731
732 /*
733 * Find the entry prior to the proposed starting address; if it's part
734 * of an existing entry, this range is bogus.
735 */
736
737 if (vm_map_lookup_entry(map, start, &temp_entry))
738 return (KERN_NO_SPACE);
739
740 prev_entry = temp_entry;
741
742 /*
743 * Assert that the next entry doesn't overlap the end point.
744 */
745
746 if ((prev_entry->next != &map->header) &&
747 (prev_entry->next->start < end))
748 return (KERN_NO_SPACE);
749
750 protoeflags = 0;
751
752 if (cow & MAP_COPY_ON_WRITE)
753 protoeflags |= MAP_ENTRY_COW|MAP_ENTRY_NEEDS_COPY;
754
755 if (cow & MAP_NOFAULT) {
756 protoeflags |= MAP_ENTRY_NOFAULT;
757
758 KASSERT(object == NULL,
759 ("vm_map_insert: paradoxical MAP_NOFAULT request"));
760 }
761 if (cow & MAP_DISABLE_SYNCER)
762 protoeflags |= MAP_ENTRY_NOSYNC;
763 if (cow & MAP_DISABLE_COREDUMP)
764 protoeflags |= MAP_ENTRY_NOCOREDUMP;
765
766 if (object) {
767 /*
768 * When object is non-NULL, it could be shared with another
769 * process. We have to set or clear OBJ_ONEMAPPING
770 * appropriately.
771 */
772 if ((object->ref_count > 1) || (object->shadow_count != 0)) {
773 vm_object_clear_flag(object, OBJ_ONEMAPPING);
774 }
775 }
776 else if ((prev_entry != &map->header) &&
777 (prev_entry->eflags == protoeflags) &&
778 (prev_entry->end == start) &&
779 (prev_entry->wired_count == 0) &&
1b874851 780 prev_entry->maptype == maptype &&
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MD
781 ((prev_entry->object.vm_object == NULL) ||
782 vm_object_coalesce(prev_entry->object.vm_object,
783 OFF_TO_IDX(prev_entry->offset),
784 (vm_size_t)(prev_entry->end - prev_entry->start),
785 (vm_size_t)(end - prev_entry->end)))) {
786 /*
787 * We were able to extend the object. Determine if we
788 * can extend the previous map entry to include the
789 * new range as well.
790 */
791 if ((prev_entry->inheritance == VM_INHERIT_DEFAULT) &&
792 (prev_entry->protection == prot) &&
793 (prev_entry->max_protection == max)) {
794 map->size += (end - prev_entry->end);
795 prev_entry->end = end;
a108bf71 796 vm_map_simplify_entry(map, prev_entry, countp);
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MD
797 return (KERN_SUCCESS);
798 }
799
800 /*
801 * If we can extend the object but cannot extend the
802 * map entry, we have to create a new map entry. We
803 * must bump the ref count on the extended object to
804 * account for it. object may be NULL.
805 */
806 object = prev_entry->object.vm_object;
807 offset = prev_entry->offset +
808 (prev_entry->end - prev_entry->start);
809 vm_object_reference(object);
810 }
811
812 /*
813 * NOTE: if conditionals fail, object can be NULL here. This occurs
814 * in things like the buffer map where we manage kva but do not manage
815 * backing objects.
816 */
817
818 /*
819 * Create a new entry
820 */
821
a108bf71 822 new_entry = vm_map_entry_create(map, countp);
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823 new_entry->start = start;
824 new_entry->end = end;
825
1b874851 826 new_entry->maptype = maptype;
984263bc
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827 new_entry->eflags = protoeflags;
828 new_entry->object.vm_object = object;
829 new_entry->offset = offset;
afeabdca 830 new_entry->aux.master_pde = 0;
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831
832 new_entry->inheritance = VM_INHERIT_DEFAULT;
833 new_entry->protection = prot;
834 new_entry->max_protection = max;
835 new_entry->wired_count = 0;
836
837 /*
838 * Insert the new entry into the list
839 */
840
841 vm_map_entry_link(map, prev_entry, new_entry);
842 map->size += new_entry->end - new_entry->start;
843
844 /*
845 * Update the free space hint
846 */
847 if ((map->first_free == prev_entry) &&
848 (prev_entry->end >= new_entry->start)) {
849 map->first_free = new_entry;
850 }
851
852#if 0
853 /*
854 * Temporarily removed to avoid MAP_STACK panic, due to
855 * MAP_STACK being a huge hack. Will be added back in
856 * when MAP_STACK (and the user stack mapping) is fixed.
857 */
858 /*
859 * It may be possible to simplify the entry
860 */
a108bf71 861 vm_map_simplify_entry(map, new_entry, countp);
984263bc
MD
862#endif
863
afeabdca
MD
864 /*
865 * Try to pre-populate the page table. Mappings governed by virtual
866 * page tables cannot be prepopulated without a lot of work, so
867 * don't try.
868 */
869 if ((cow & (MAP_PREFAULT|MAP_PREFAULT_PARTIAL)) &&
870 maptype != VM_MAPTYPE_VPAGETABLE) {
083a7402 871 pmap_object_init_pt(map->pmap, start, prot,
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MD
872 object, OFF_TO_IDX(offset), end - start,
873 cow & MAP_PREFAULT_PARTIAL);
874 }
875
876 return (KERN_SUCCESS);
877}
878
879/*
880 * Find sufficient space for `length' bytes in the given map, starting at
881 * `start'. The map must be locked. Returns 0 on success, 1 on no space.
e9bb90e8
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882 *
883 * This function will returned an arbitrarily aligned pointer. If no
884 * particular alignment is required you should pass align as 1. Note that
885 * the map may return PAGE_SIZE aligned pointers if all the lengths used in
886 * the map are a multiple of PAGE_SIZE, even if you pass a smaller align
887 * argument.
888 *
889 * 'align' should be a power of 2 but is not required to be.
984263bc
MD
890 */
891int
e9bb90e8
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892vm_map_findspace(
893 vm_map_t map,
894 vm_offset_t start,
895 vm_size_t length,
896 vm_offset_t align,
897 vm_offset_t *addr)
984263bc
MD
898{
899 vm_map_entry_t entry, next;
900 vm_offset_t end;
e9bb90e8 901 vm_offset_t align_mask;
984263bc
MD
902
903 if (start < map->min_offset)
904 start = map->min_offset;
905 if (start > map->max_offset)
906 return (1);
907
e9bb90e8
MD
908 /*
909 * If the alignment is not a power of 2 we will have to use
910 * a mod/division, set align_mask to a special value.
911 */
912 if ((align | (align - 1)) + 1 != (align << 1))
913 align_mask = (vm_offset_t)-1;
914 else
915 align_mask = align - 1;
916
a108bf71 917retry:
984263bc
MD
918 /*
919 * Look for the first possible address; if there's already something
920 * at this address, we have to start after it.
921 */
922 if (start == map->min_offset) {
923 if ((entry = map->first_free) != &map->header)
924 start = entry->end;
925 } else {
926 vm_map_entry_t tmp;
927
928 if (vm_map_lookup_entry(map, start, &tmp))
929 start = tmp->end;
930 entry = tmp;
931 }
932
933 /*
934 * Look through the rest of the map, trying to fit a new region in the
935 * gap between existing regions, or after the very last region.
936 */
937 for (;; start = (entry = next)->end) {
e9bb90e8
MD
938 /*
939 * Adjust the proposed start by the requested alignment,
940 * be sure that we didn't wrap the address.
941 */
942 if (align_mask == (vm_offset_t)-1)
943 end = ((start + align - 1) / align) * align;
944 else
945 end = (start + align_mask) & ~align_mask;
946 if (end < start)
947 return (1);
948 start = end;
984263bc
MD
949 /*
950 * Find the end of the proposed new region. Be sure we didn't
e9bb90e8
MD
951 * go beyond the end of the map, or wrap around the address.
952 * Then check to see if this is the last entry or if the
953 * proposed end fits in the gap between this and the next
954 * entry.
984263bc
MD
955 */
956 end = start + length;
957 if (end > map->max_offset || end < start)
958 return (1);
959 next = entry->next;
960 if (next == &map->header || next->start >= end)
961 break;
962 }
686dbf64 963 map->hint = entry;
e4846942 964 if (map == &kernel_map) {
984263bc
MD
965 vm_offset_t ksize;
966 if ((ksize = round_page(start + length)) > kernel_vm_end) {
967 pmap_growkernel(ksize);
a108bf71 968 goto retry;
984263bc
MD
969 }
970 }
a108bf71 971 *addr = start;
984263bc
MD
972 return (0);
973}
974
975/*
976 * vm_map_find finds an unallocated region in the target address
977 * map with the given length. The search is defined to be
978 * first-fit from the specified address; the region found is
979 * returned in the same parameter.
980 *
981 * If object is non-NULL, ref count must be bumped by caller
982 * prior to making call to account for the new entry.
983 */
984int
985vm_map_find(vm_map_t map, vm_object_t object, vm_ooffset_t offset,
1b874851
MD
986 vm_offset_t *addr, vm_size_t length,
987 boolean_t find_space,
988 vm_maptype_t maptype,
989 vm_prot_t prot, vm_prot_t max,
990 int cow)
984263bc
MD
991{
992 vm_offset_t start;
03aa8d99 993 int result;
a108bf71 994 int count;
984263bc
MD
995
996 start = *addr;
997
a108bf71 998 count = vm_map_entry_reserve(MAP_RESERVE_COUNT);
984263bc
MD
999 vm_map_lock(map);
1000 if (find_space) {
e9bb90e8 1001 if (vm_map_findspace(map, start, length, 1, addr)) {
984263bc 1002 vm_map_unlock(map);
a108bf71 1003 vm_map_entry_release(count);
984263bc
MD
1004 return (KERN_NO_SPACE);
1005 }
1006 start = *addr;
1007 }
a108bf71 1008 result = vm_map_insert(map, &count, object, offset,
1b874851
MD
1009 start, start + length,
1010 maptype,
1011 prot, max,
1012 cow);
984263bc 1013 vm_map_unlock(map);
a108bf71 1014 vm_map_entry_release(count);
984263bc 1015
984263bc
MD
1016 return (result);
1017}
1018
1019/*
1020 * vm_map_simplify_entry:
1021 *
1022 * Simplify the given map entry by merging with either neighbor. This
1023 * routine also has the ability to merge with both neighbors.
1024 *
1025 * The map must be locked.
1026 *
1027 * This routine guarentees that the passed entry remains valid (though
1028 * possibly extended). When merging, this routine may delete one or
1029 * both neighbors. No action is taken on entries which have their
1030 * in-transition flag set.
1031 */
1032void
a108bf71 1033vm_map_simplify_entry(vm_map_t map, vm_map_entry_t entry, int *countp)
984263bc
MD
1034{
1035 vm_map_entry_t next, prev;
1036 vm_size_t prevsize, esize;
1037
1b874851 1038 if (entry->eflags & MAP_ENTRY_IN_TRANSITION) {
12e4aaff 1039 ++mycpu->gd_cnt.v_intrans_coll;
984263bc
MD
1040 return;
1041 }
1042
1b874851
MD
1043 if (entry->maptype == VM_MAPTYPE_SUBMAP)
1044 return;
1045
984263bc
MD
1046 prev = entry->prev;
1047 if (prev != &map->header) {
1048 prevsize = prev->end - prev->start;
1049 if ( (prev->end == entry->start) &&
1b874851 1050 (prev->maptype == entry->maptype) &&
984263bc
MD
1051 (prev->object.vm_object == entry->object.vm_object) &&
1052 (!prev->object.vm_object ||
1053 (prev->offset + prevsize == entry->offset)) &&
1054 (prev->eflags == entry->eflags) &&
1055 (prev->protection == entry->protection) &&
1056 (prev->max_protection == entry->max_protection) &&
1057 (prev->inheritance == entry->inheritance) &&
1058 (prev->wired_count == entry->wired_count)) {
1059 if (map->first_free == prev)
1060 map->first_free = entry;
1061 if (map->hint == prev)
1062 map->hint = entry;
1063 vm_map_entry_unlink(map, prev);
1064 entry->start = prev->start;
1065 entry->offset = prev->offset;
1066 if (prev->object.vm_object)
1067 vm_object_deallocate(prev->object.vm_object);
a108bf71 1068 vm_map_entry_dispose(map, prev, countp);
984263bc
MD
1069 }
1070 }
1071
1072 next = entry->next;
1073 if (next != &map->header) {
1074 esize = entry->end - entry->start;
1075 if ((entry->end == next->start) &&
1b874851 1076 (next->maptype == entry->maptype) &&
984263bc
MD
1077 (next->object.vm_object == entry->object.vm_object) &&
1078 (!entry->object.vm_object ||
1079 (entry->offset + esize == next->offset)) &&
1080 (next->eflags == entry->eflags) &&
1081 (next->protection == entry->protection) &&
1082 (next->max_protection == entry->max_protection) &&
1083 (next->inheritance == entry->inheritance) &&
1084 (next->wired_count == entry->wired_count)) {
1085 if (map->first_free == next)
1086 map->first_free = entry;
1087 if (map->hint == next)
1088 map->hint = entry;
1089 vm_map_entry_unlink(map, next);
1090 entry->end = next->end;
1091 if (next->object.vm_object)
1092 vm_object_deallocate(next->object.vm_object);
a108bf71 1093 vm_map_entry_dispose(map, next, countp);
984263bc
MD
1094 }
1095 }
1096}
1097/*
1098 * vm_map_clip_start: [ internal use only ]
1099 *
1100 * Asserts that the given entry begins at or after
1101 * the specified address; if necessary,
1102 * it splits the entry into two.
1103 */
a108bf71 1104#define vm_map_clip_start(map, entry, startaddr, countp) \
984263bc
MD
1105{ \
1106 if (startaddr > entry->start) \
a108bf71 1107 _vm_map_clip_start(map, entry, startaddr, countp); \
984263bc
MD
1108}
1109
1110/*
1111 * This routine is called only when it is known that
1112 * the entry must be split.
1113 */
1114static void
a108bf71 1115_vm_map_clip_start(vm_map_t map, vm_map_entry_t entry, vm_offset_t start, int *countp)
984263bc
MD
1116{
1117 vm_map_entry_t new_entry;
1118
1119 /*
1120 * Split off the front portion -- note that we must insert the new
1121 * entry BEFORE this one, so that this entry has the specified
1122 * starting address.
1123 */
1124
a108bf71 1125 vm_map_simplify_entry(map, entry, countp);
984263bc
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1126
1127 /*
1128 * If there is no object backing this entry, we might as well create
1129 * one now. If we defer it, an object can get created after the map
1130 * is clipped, and individual objects will be created for the split-up
1131 * map. This is a bit of a hack, but is also about the best place to
1132 * put this improvement.
1133 */
984263bc 1134 if (entry->object.vm_object == NULL && !map->system_map) {
53025830 1135 vm_map_entry_allocate_object(entry);
984263bc
MD
1136 }
1137
a108bf71 1138 new_entry = vm_map_entry_create(map, countp);
984263bc
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1139 *new_entry = *entry;
1140
1141 new_entry->end = start;
1142 entry->offset += (start - entry->start);
1143 entry->start = start;
1144
1145 vm_map_entry_link(map, entry->prev, new_entry);
1146
1b874851
MD
1147 switch(entry->maptype) {
1148 case VM_MAPTYPE_NORMAL:
1149 case VM_MAPTYPE_VPAGETABLE:
984263bc 1150 vm_object_reference(new_entry->object.vm_object);
1b874851
MD
1151 break;
1152 default:
1153 break;
984263bc
MD
1154 }
1155}
1156
1157/*
1158 * vm_map_clip_end: [ internal use only ]
1159 *
1160 * Asserts that the given entry ends at or before
1161 * the specified address; if necessary,
1162 * it splits the entry into two.
1163 */
1164
a108bf71 1165#define vm_map_clip_end(map, entry, endaddr, countp) \
984263bc
MD
1166{ \
1167 if (endaddr < entry->end) \
a108bf71 1168 _vm_map_clip_end(map, entry, endaddr, countp); \
984263bc
MD
1169}
1170
1171/*
1172 * This routine is called only when it is known that
1173 * the entry must be split.
1174 */
1175static void
a108bf71 1176_vm_map_clip_end(vm_map_t map, vm_map_entry_t entry, vm_offset_t end, int *countp)
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MD
1177{
1178 vm_map_entry_t new_entry;
1179
1180 /*
1181 * If there is no object backing this entry, we might as well create
1182 * one now. If we defer it, an object can get created after the map
1183 * is clipped, and individual objects will be created for the split-up
1184 * map. This is a bit of a hack, but is also about the best place to
1185 * put this improvement.
1186 */
1187
1188 if (entry->object.vm_object == NULL && !map->system_map) {
53025830 1189 vm_map_entry_allocate_object(entry);
984263bc
MD
1190 }
1191
1192 /*
1193 * Create a new entry and insert it AFTER the specified entry
1194 */
1195
a108bf71 1196 new_entry = vm_map_entry_create(map, countp);
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MD
1197 *new_entry = *entry;
1198
1199 new_entry->start = entry->end = end;
1200 new_entry->offset += (end - entry->start);
1201
1202 vm_map_entry_link(map, entry, new_entry);
1203
1b874851
MD
1204 switch(entry->maptype) {
1205 case VM_MAPTYPE_NORMAL:
1206 case VM_MAPTYPE_VPAGETABLE:
984263bc 1207 vm_object_reference(new_entry->object.vm_object);
1b874851
MD
1208 break;
1209 default:
1210 break;
984263bc
MD
1211 }
1212}
1213
1214/*
1215 * VM_MAP_RANGE_CHECK: [ internal use only ]
1216 *
1217 * Asserts that the starting and ending region
1218 * addresses fall within the valid range of the map.
1219 */
1220#define VM_MAP_RANGE_CHECK(map, start, end) \
1221 { \
1222 if (start < vm_map_min(map)) \
1223 start = vm_map_min(map); \
1224 if (end > vm_map_max(map)) \
1225 end = vm_map_max(map); \
1226 if (start > end) \
1227 start = end; \
1228 }
1229
1230/*
1231 * vm_map_transition_wait: [ kernel use only ]
1232 *
1233 * Used to block when an in-transition collison occurs. The map
1234 * is unlocked for the sleep and relocked before the return.
1235 */
1236static
1237void
1238vm_map_transition_wait(vm_map_t map)
1239{
1240 vm_map_unlock(map);
377d4740 1241 tsleep(map, 0, "vment", 0);
984263bc
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1242 vm_map_lock(map);
1243}
1244
1245/*
1246 * CLIP_CHECK_BACK
1247 * CLIP_CHECK_FWD
1248 *
1249 * When we do blocking operations with the map lock held it is
1250 * possible that a clip might have occured on our in-transit entry,
1251 * requiring an adjustment to the entry in our loop. These macros
1252 * help the pageable and clip_range code deal with the case. The
1253 * conditional costs virtually nothing if no clipping has occured.
1254 */
1255
1256#define CLIP_CHECK_BACK(entry, save_start) \
1257 do { \
1258 while (entry->start != save_start) { \
1259 entry = entry->prev; \
1260 KASSERT(entry != &map->header, ("bad entry clip")); \
1261 } \
1262 } while(0)
1263
1264#define CLIP_CHECK_FWD(entry, save_end) \
1265 do { \
1266 while (entry->end != save_end) { \
1267 entry = entry->next; \
1268 KASSERT(entry != &map->header, ("bad entry clip")); \
1269 } \
1270 } while(0)
1271
1272
1273/*
1274 * vm_map_clip_range: [ kernel use only ]
1275 *
1276 * Clip the specified range and return the base entry. The
1277 * range may cover several entries starting at the returned base
1278 * and the first and last entry in the covering sequence will be
1279 * properly clipped to the requested start and end address.
1280 *
1281 * If no holes are allowed you should pass the MAP_CLIP_NO_HOLES
1282 * flag.
1283 *
1284 * The MAP_ENTRY_IN_TRANSITION flag will be set for the entries
1285 * covered by the requested range.
1286 *
1287 * The map must be exclusively locked on entry and will remain locked
1288 * on return. If no range exists or the range contains holes and you
1289 * specified that no holes were allowed, NULL will be returned. This
1290 * routine may temporarily unlock the map in order avoid a deadlock when
1291 * sleeping.
1292 */
1293static
1294vm_map_entry_t
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1295vm_map_clip_range(vm_map_t map, vm_offset_t start, vm_offset_t end,
1296 int *countp, int flags)
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1297{
1298 vm_map_entry_t start_entry;
1299 vm_map_entry_t entry;
1300
1301 /*
1302 * Locate the entry and effect initial clipping. The in-transition
1303 * case does not occur very often so do not try to optimize it.
1304 */
1305again:
1306 if (vm_map_lookup_entry(map, start, &start_entry) == FALSE)
1307 return (NULL);
1308 entry = start_entry;
1309 if (entry->eflags & MAP_ENTRY_IN_TRANSITION) {
1310 entry->eflags |= MAP_ENTRY_NEEDS_WAKEUP;
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1311 ++mycpu->gd_cnt.v_intrans_coll;
1312 ++mycpu->gd_cnt.v_intrans_wait;
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1313 vm_map_transition_wait(map);
1314 /*
1315 * entry and/or start_entry may have been clipped while
1316 * we slept, or may have gone away entirely. We have
1317 * to restart from the lookup.
1318 */
1319 goto again;
1320 }
1321 /*
1322 * Since we hold an exclusive map lock we do not have to restart
1323 * after clipping, even though clipping may block in zalloc.
1324 */
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1325 vm_map_clip_start(map, entry, start, countp);
1326 vm_map_clip_end(map, entry, end, countp);
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1327 entry->eflags |= MAP_ENTRY_IN_TRANSITION;
1328
1329 /*
1330 * Scan entries covered by the range. When working on the next
1331 * entry a restart need only re-loop on the current entry which
1332 * we have already locked, since 'next' may have changed. Also,
1333 * even though entry is safe, it may have been clipped so we
1334 * have to iterate forwards through the clip after sleeping.
1335 */
1336 while (entry->next != &map->header && entry->next->start < end) {
1337 vm_map_entry_t next = entry->next;
1338
1339 if (flags & MAP_CLIP_NO_HOLES) {
1340 if (next->start > entry->end) {
1341 vm_map_unclip_range(map, start_entry,
a108bf71 1342 start, entry->end, countp, flags);
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1343 return(NULL);
1344 }
1345 }
1346
1347 if (next->eflags & MAP_ENTRY_IN_TRANSITION) {
1348 vm_offset_t save_end = entry->end;
1349 next->eflags |= MAP_ENTRY_NEEDS_WAKEUP;
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1350 ++mycpu->gd_cnt.v_intrans_coll;
1351 ++mycpu->gd_cnt.v_intrans_wait;
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1352 vm_map_transition_wait(map);
1353
1354 /*
1355 * clips might have occured while we blocked.
1356 */
1357 CLIP_CHECK_FWD(entry, save_end);
1358 CLIP_CHECK_BACK(start_entry, start);
1359 continue;
1360 }
1361 /*
1362 * No restart necessary even though clip_end may block, we
1363 * are holding the map lock.
1364 */
a108bf71 1365 vm_map_clip_end(map, next, end, countp);
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1366 next->eflags |= MAP_ENTRY_IN_TRANSITION;
1367 entry = next;
1368 }
1369 if (flags & MAP_CLIP_NO_HOLES) {
1370 if (entry->end != end) {
1371 vm_map_unclip_range(map, start_entry,
a108bf71 1372 start, entry->end, countp, flags);
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1373 return(NULL);
1374 }
1375 }
1376 return(start_entry);
1377}
1378
1379/*
1380 * vm_map_unclip_range: [ kernel use only ]
1381 *
1382 * Undo the effect of vm_map_clip_range(). You should pass the same
1383 * flags and the same range that you passed to vm_map_clip_range().
1384 * This code will clear the in-transition flag on the entries and
1385 * wake up anyone waiting. This code will also simplify the sequence
1386 * and attempt to merge it with entries before and after the sequence.
1387 *
1388 * The map must be locked on entry and will remain locked on return.
1389 *
1390 * Note that you should also pass the start_entry returned by
1391 * vm_map_clip_range(). However, if you block between the two calls
1392 * with the map unlocked please be aware that the start_entry may
1393 * have been clipped and you may need to scan it backwards to find
1394 * the entry corresponding with the original start address. You are
1395 * responsible for this, vm_map_unclip_range() expects the correct
1396 * start_entry to be passed to it and will KASSERT otherwise.
1397 */
1398static
1399void
1400vm_map_unclip_range(
1401 vm_map_t map,
1402 vm_map_entry_t start_entry,
1403 vm_offset_t start,
1404 vm_offset_t end,
a108bf71 1405 int *countp,
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1406 int flags)
1407{
1408 vm_map_entry_t entry;
1409
1410 entry = start_entry;
1411
1412 KASSERT(entry->start == start, ("unclip_range: illegal base entry"));
1413 while (entry != &map->header && entry->start < end) {
1414 KASSERT(entry->eflags & MAP_ENTRY_IN_TRANSITION, ("in-transition flag not set during unclip on: %p", entry));
1415 KASSERT(entry->end <= end, ("unclip_range: tail wasn't clipped"));
1416 entry->eflags &= ~MAP_ENTRY_IN_TRANSITION;
1417 if (entry->eflags & MAP_ENTRY_NEEDS_WAKEUP) {
1418 entry->eflags &= ~MAP_ENTRY_NEEDS_WAKEUP;
1419 wakeup(map);
1420 }
1421 entry = entry->next;
1422 }
1423
1424 /*
1425 * Simplification does not block so there is no restart case.
1426 */
1427 entry = start_entry;
1428 while (entry != &map->header && entry->start < end) {
a108bf71 1429 vm_map_simplify_entry(map, entry, countp);
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1430 entry = entry->next;
1431 }
1432}
1433
1434/*
1435 * vm_map_submap: [ kernel use only ]
1436 *
1437 * Mark the given range as handled by a subordinate map.
1438 *
1439 * This range must have been created with vm_map_find,
1440 * and no other operations may have been performed on this
1441 * range prior to calling vm_map_submap.
1442 *
1443 * Only a limited number of operations can be performed
1444 * within this rage after calling vm_map_submap:
1445 * vm_fault
1446 * [Don't try vm_map_copy!]
1447 *
1448 * To remove a submapping, one must first remove the
1449 * range from the superior map, and then destroy the
1450 * submap (if desired). [Better yet, don't try it.]
1451 */
1452int
a108bf71 1453vm_map_submap(vm_map_t map, vm_offset_t start, vm_offset_t end, vm_map_t submap)
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1454{
1455 vm_map_entry_t entry;
1456 int result = KERN_INVALID_ARGUMENT;
a108bf71 1457 int count;
984263bc 1458
a108bf71 1459 count = vm_map_entry_reserve(MAP_RESERVE_COUNT);
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1460 vm_map_lock(map);
1461
1462 VM_MAP_RANGE_CHECK(map, start, end);
1463
1464 if (vm_map_lookup_entry(map, start, &entry)) {
a108bf71 1465 vm_map_clip_start(map, entry, start, &count);
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1466 } else {
1467 entry = entry->next;
1468 }
1469
a108bf71 1470 vm_map_clip_end(map, entry, end, &count);
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1471
1472 if ((entry->start == start) && (entry->end == end) &&
1473 ((entry->eflags & MAP_ENTRY_COW) == 0) &&
1474 (entry->object.vm_object == NULL)) {
1475 entry->object.sub_map = submap;
1b874851 1476 entry->maptype = VM_MAPTYPE_SUBMAP;
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1477 result = KERN_SUCCESS;
1478 }
1479 vm_map_unlock(map);
a108bf71 1480 vm_map_entry_release(count);
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1481
1482 return (result);
1483}
1484
1485/*
1b874851 1486 * vm_map_protect:
984263bc 1487 *
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1488 * Sets the protection of the specified address region in the target map.
1489 * If "set_max" is specified, the maximum protection is to be set;
1490 * otherwise, only the current protection is affected.
1491 *
1492 * The protection is not applicable to submaps, but is applicable to normal
1493 * maps and maps governed by virtual page tables. For example, when operating
1494 * on a virtual page table our protection basically controls how COW occurs
1495 * on the backing object, whereas the virtual page table abstraction itself
1496 * is an abstraction for userland.
984263bc
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1497 */
1498int
1499vm_map_protect(vm_map_t map, vm_offset_t start, vm_offset_t end,
1500 vm_prot_t new_prot, boolean_t set_max)
1501{
1502 vm_map_entry_t current;
1503 vm_map_entry_t entry;
a108bf71 1504 int count;
984263bc 1505
a108bf71 1506 count = vm_map_entry_reserve(MAP_RESERVE_COUNT);
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1507 vm_map_lock(map);
1508
1509 VM_MAP_RANGE_CHECK(map, start, end);
1510
1511 if (vm_map_lookup_entry(map, start, &entry)) {
a108bf71 1512 vm_map_clip_start(map, entry, start, &count);
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MD
1513 } else {
1514 entry = entry->next;
1515 }
1516
1517 /*
1518 * Make a first pass to check for protection violations.
1519 */
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MD
1520 current = entry;
1521 while ((current != &map->header) && (current->start < end)) {
1b874851 1522 if (current->maptype == VM_MAPTYPE_SUBMAP) {
984263bc 1523 vm_map_unlock(map);
a108bf71 1524 vm_map_entry_release(count);
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MD
1525 return (KERN_INVALID_ARGUMENT);
1526 }
1527 if ((new_prot & current->max_protection) != new_prot) {
1528 vm_map_unlock(map);
a108bf71 1529 vm_map_entry_release(count);
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MD
1530 return (KERN_PROTECTION_FAILURE);
1531 }
1532 current = current->next;
1533 }
1534
1535 /*
1536 * Go back and fix up protections. [Note that clipping is not
1537 * necessary the second time.]
1538 */
984263bc
MD
1539 current = entry;
1540
1541 while ((current != &map->header) && (current->start < end)) {
1542 vm_prot_t old_prot;
1543
a108bf71 1544 vm_map_clip_end(map, current, end, &count);
984263bc
MD
1545
1546 old_prot = current->protection;
1b874851 1547 if (set_max) {
984263bc
MD
1548 current->protection =
1549 (current->max_protection = new_prot) &
1550 old_prot;
1b874851 1551 } else {
984263bc 1552 current->protection = new_prot;
1b874851 1553 }
984263bc
MD
1554
1555 /*
1556 * Update physical map if necessary. Worry about copy-on-write
1557 * here -- CHECK THIS XXX
1558 */
1559
1560 if (current->protection != old_prot) {
1561#define MASK(entry) (((entry)->eflags & MAP_ENTRY_COW) ? ~VM_PROT_WRITE : \
1562 VM_PROT_ALL)
1563
1564 pmap_protect(map->pmap, current->start,
1565 current->end,
1566 current->protection & MASK(current));
1567#undef MASK
1568 }
1569
a108bf71 1570 vm_map_simplify_entry(map, current, &count);
984263bc
MD
1571
1572 current = current->next;
1573 }
1574
1575 vm_map_unlock(map);
a108bf71 1576 vm_map_entry_release(count);
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MD
1577 return (KERN_SUCCESS);
1578}
1579
1580/*
1581 * vm_map_madvise:
1582 *
1583 * This routine traverses a processes map handling the madvise
1584 * system call. Advisories are classified as either those effecting
1585 * the vm_map_entry structure, or those effecting the underlying
1586 * objects.
afeabdca
MD
1587 *
1588 * The <value> argument is used for extended madvise calls.
984263bc 1589 */
984263bc 1590int
afeabdca
MD
1591vm_map_madvise(vm_map_t map, vm_offset_t start, vm_offset_t end,
1592 int behav, off_t value)
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MD
1593{
1594 vm_map_entry_t current, entry;
1595 int modify_map = 0;
afeabdca 1596 int error = 0;
a108bf71 1597 int count;
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MD
1598
1599 /*
1600 * Some madvise calls directly modify the vm_map_entry, in which case
1601 * we need to use an exclusive lock on the map and we need to perform
1602 * various clipping operations. Otherwise we only need a read-lock
1603 * on the map.
1604 */
1605
a108bf71
MD
1606 count = vm_map_entry_reserve(MAP_RESERVE_COUNT);
1607
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1608 switch(behav) {
1609 case MADV_NORMAL:
1610 case MADV_SEQUENTIAL:
1611 case MADV_RANDOM:
1612 case MADV_NOSYNC:
1613 case MADV_AUTOSYNC:
1614 case MADV_NOCORE:
1615 case MADV_CORE:
afeabdca
MD
1616 case MADV_SETMAP:
1617 case MADV_INVAL:
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MD
1618 modify_map = 1;
1619 vm_map_lock(map);
1620 break;
1621 case MADV_WILLNEED:
1622 case MADV_DONTNEED:
1623 case MADV_FREE:
1624 vm_map_lock_read(map);
1625 break;
1626 default:
a108bf71 1627 vm_map_entry_release(count);
afeabdca 1628 return (EINVAL);
984263bc
MD
1629 }
1630
1631 /*
1632 * Locate starting entry and clip if necessary.
1633 */
1634
1635 VM_MAP_RANGE_CHECK(map, start, end);
1636
1637 if (vm_map_lookup_entry(map, start, &entry)) {
1638 if (modify_map)
a108bf71 1639 vm_map_clip_start(map, entry, start, &count);
984263bc
MD
1640 } else {
1641 entry = entry->next;
1642 }
1643
1644 if (modify_map) {
1645 /*
1646 * madvise behaviors that are implemented in the vm_map_entry.
1647 *
1648 * We clip the vm_map_entry so that behavioral changes are
1649 * limited to the specified address range.
1650 */
1651 for (current = entry;
1652 (current != &map->header) && (current->start < end);
1653 current = current->next
1654 ) {
1b874851 1655 if (current->maptype == VM_MAPTYPE_SUBMAP)
984263bc
MD
1656 continue;
1657
a108bf71 1658 vm_map_clip_end(map, current, end, &count);
984263bc
MD
1659
1660 switch (behav) {
1661 case MADV_NORMAL:
1662 vm_map_entry_set_behavior(current, MAP_ENTRY_BEHAV_NORMAL);
1663 break;
1664 case MADV_SEQUENTIAL:
1665 vm_map_entry_set_behavior(current, MAP_ENTRY_BEHAV_SEQUENTIAL);
1666 break;
1667 case MADV_RANDOM:
1668 vm_map_entry_set_behavior(current, MAP_ENTRY_BEHAV_RANDOM);
1669 break;
1670 case MADV_NOSYNC:
1671 current->eflags |= MAP_ENTRY_NOSYNC;
1672 break;
1673 case MADV_AUTOSYNC:
1674 current->eflags &= ~MAP_ENTRY_NOSYNC;
1675 break;
1676 case MADV_NOCORE:
1677 current->eflags |= MAP_ENTRY_NOCOREDUMP;
1678 break;
1679 case MADV_CORE:
1680 current->eflags &= ~MAP_ENTRY_NOCOREDUMP;
1681 break;
afeabdca
MD
1682 case MADV_INVAL:
1683 /*
1684 * Invalidate the related pmap entries, used
1685 * to flush portions of the real kernel's
1686 * pmap when the caller has removed or
1687 * modified existing mappings in a virtual
1688 * page table.
1689 */
1690 pmap_remove(map->pmap,
1691 current->start, current->end);
1692 break;
1693 case MADV_SETMAP:
1694 /*
1695 * Set the page directory page for a map
1696 * governed by a virtual page table. Mark
1697 * the entry as being governed by a virtual
1698 * page table if it is not.
1699 *
1700 * XXX the page directory page is stored
1701 * in the avail_ssize field if the map_entry.
1702 *
1703 * XXX the map simplification code does not
1704 * compare this field so weird things may
1705 * happen if you do not apply this function
1706 * to the entire mapping governed by the
1707 * virtual page table.
1708 */
1709 if (current->maptype != VM_MAPTYPE_VPAGETABLE) {
1710 error = EINVAL;
1711 break;
1712 }
1713 current->aux.master_pde = value;
1714 pmap_remove(map->pmap,
1715 current->start, current->end);
1716 break;
984263bc 1717 default:
afeabdca 1718 error = EINVAL;
984263bc
MD
1719 break;
1720 }
a108bf71 1721 vm_map_simplify_entry(map, current, &count);
984263bc
MD
1722 }
1723 vm_map_unlock(map);
1724 } else {
1725 vm_pindex_t pindex;
1726 int count;
1727
1728 /*
1729 * madvise behaviors that are implemented in the underlying
1730 * vm_object.
1731 *
1732 * Since we don't clip the vm_map_entry, we have to clip
1733 * the vm_object pindex and count.
1b874851
MD
1734 *
1735 * NOTE! We currently do not support these functions on
1736 * virtual page tables.
984263bc
MD
1737 */
1738 for (current = entry;
1739 (current != &map->header) && (current->start < end);
1740 current = current->next
1741 ) {
1742 vm_offset_t useStart;
1743
1b874851 1744 if (current->maptype != VM_MAPTYPE_NORMAL)
984263bc
MD
1745 continue;
1746
1747 pindex = OFF_TO_IDX(current->offset);
1748 count = atop(current->end - current->start);
1749 useStart = current->start;
1750
1751 if (current->start < start) {
1752 pindex += atop(start - current->start);
1753 count -= atop(start - current->start);
1754 useStart = start;
1755 }
1756 if (current->end > end)
1757 count -= atop(current->end - end);
1758
1759 if (count <= 0)
1760 continue;
1761
1762 vm_object_madvise(current->object.vm_object,
1763 pindex, count, behav);
afeabdca
MD
1764
1765 /*
1766 * Try to populate the page table. Mappings governed
1767 * by virtual page tables cannot be pre-populated
1768 * without a lot of work so don't try.
1769 */
1770 if (behav == MADV_WILLNEED &&
1771 current->maptype != VM_MAPTYPE_VPAGETABLE) {
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1772 pmap_object_init_pt(
1773 map->pmap,
1774 useStart,
083a7402 1775 current->protection,
984263bc
MD
1776 current->object.vm_object,
1777 pindex,
1778 (count << PAGE_SHIFT),
1779 MAP_PREFAULT_MADVISE
1780 );
1781 }
1782 }
1783 vm_map_unlock_read(map);
1784 }
a108bf71 1785 vm_map_entry_release(count);
afeabdca 1786 return(error);
984263bc
MD
1787}
1788
1789
1790/*
1791 * vm_map_inherit:
1792 *
1793 * Sets the inheritance of the specified address
1794 * range in the target map. Inheritance
1795 * affects how the map will be shared with
1796 * child maps at the time of vm_map_fork.
1797 */
1798int
1799vm_map_inherit(vm_map_t map, vm_offset_t start, vm_offset_t end,
1800 vm_inherit_t new_inheritance)
1801{
1802 vm_map_entry_t entry;
1803 vm_map_entry_t temp_entry;
a108bf71 1804 int count;
984263bc
MD
1805
1806 switch (new_inheritance) {
1807 case VM_INHERIT_NONE:
1808 case VM_INHERIT_COPY:
1809 case VM_INHERIT_SHARE:
1810 break;
1811 default:
1812 return (KERN_INVALID_ARGUMENT);
1813 }
1814
a108bf71 1815 count = vm_map_entry_reserve(MAP_RESERVE_COUNT);
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MD
1816 vm_map_lock(map);
1817
1818 VM_MAP_RANGE_CHECK(map, start, end);
1819
1820 if (vm_map_lookup_entry(map, start, &temp_entry)) {
1821 entry = temp_entry;
a108bf71 1822 vm_map_clip_start(map, entry, start, &count);
984263bc
MD
1823 } else
1824 entry = temp_entry->next;
1825
1826 while ((entry != &map->header) && (entry->start < end)) {
a108bf71 1827 vm_map_clip_end(map, entry, end, &count);
984263bc
MD
1828
1829 entry->inheritance = new_inheritance;
1830
a108bf71 1831 vm_map_simplify_entry(map, entry, &count);
984263bc
MD
1832
1833 entry = entry->next;
1834 }
984263bc 1835 vm_map_unlock(map);
a108bf71 1836 vm_map_entry_release(count);
984263bc
MD
1837 return (KERN_SUCCESS);
1838}
1839
1840/*
1841 * Implement the semantics of mlock
1842 */
1843int
57e43348
MD
1844vm_map_unwire(vm_map_t map, vm_offset_t start, vm_offset_t real_end,
1845 boolean_t new_pageable)
984263bc
MD
1846{
1847 vm_map_entry_t entry;
1848 vm_map_entry_t start_entry;
1849 vm_offset_t end;
1850 int rv = KERN_SUCCESS;
a108bf71 1851 int count;
984263bc 1852
a108bf71 1853 count = vm_map_entry_reserve(MAP_RESERVE_COUNT);
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MD
1854 vm_map_lock(map);
1855 VM_MAP_RANGE_CHECK(map, start, real_end);
1856 end = real_end;
1857
a108bf71 1858 start_entry = vm_map_clip_range(map, start, end, &count, MAP_CLIP_NO_HOLES);
984263bc
MD
1859 if (start_entry == NULL) {
1860 vm_map_unlock(map);
a108bf71 1861 vm_map_entry_release(count);
984263bc
MD
1862 return (KERN_INVALID_ADDRESS);
1863 }
1864
1865 if (new_pageable == 0) {
1866 entry = start_entry;
1867 while ((entry != &map->header) && (entry->start < end)) {
1868 vm_offset_t save_start;
1869 vm_offset_t save_end;
1870
1871 /*
1872 * Already user wired or hard wired (trivial cases)
1873 */
1874 if (entry->eflags & MAP_ENTRY_USER_WIRED) {
1875 entry = entry->next;
1876 continue;
1877 }
1878 if (entry->wired_count != 0) {
1879 entry->wired_count++;
1880 entry->eflags |= MAP_ENTRY_USER_WIRED;
1881 entry = entry->next;
1882 continue;
1883 }
1884
1885 /*
1886 * A new wiring requires instantiation of appropriate
1887 * management structures and the faulting in of the
1888 * page.
1889 */
1b874851 1890 if (entry->maptype != VM_MAPTYPE_SUBMAP) {
984263bc
MD
1891 int copyflag = entry->eflags & MAP_ENTRY_NEEDS_COPY;
1892 if (copyflag && ((entry->protection & VM_PROT_WRITE) != 0)) {
53025830 1893 vm_map_entry_shadow(entry);
984263bc
MD
1894 } else if (entry->object.vm_object == NULL &&
1895 !map->system_map) {
53025830 1896 vm_map_entry_allocate_object(entry);
984263bc
MD
1897 }
1898 }
1899 entry->wired_count++;
1900 entry->eflags |= MAP_ENTRY_USER_WIRED;
1901
1902 /*
f2d22ebf
MD
1903 * Now fault in the area. Note that vm_fault_wire()
1904 * may release the map lock temporarily, it will be
1905 * relocked on return. The in-transition
984263bc
MD
1906 * flag protects the entries.
1907 */
1908 save_start = entry->start;
1909 save_end = entry->end;
f2d22ebf 1910 rv = vm_fault_wire(map, entry, TRUE);
984263bc
MD
1911 if (rv) {
1912 CLIP_CHECK_BACK(entry, save_start);
1913 for (;;) {
1914 KASSERT(entry->wired_count == 1, ("bad wired_count on entry"));
1915 entry->eflags &= ~MAP_ENTRY_USER_WIRED;
1916 entry->wired_count = 0;
1917 if (entry->end == save_end)
1918 break;
1919 entry = entry->next;
1920 KASSERT(entry != &map->header, ("bad entry clip during backout"));
1921 }
1922 end = save_start; /* unwire the rest */
1923 break;
1924 }
1925 /*
1926 * note that even though the entry might have been
1927 * clipped, the USER_WIRED flag we set prevents
1928 * duplication so we do not have to do a
1929 * clip check.
1930 */
1931 entry = entry->next;
1932 }
1933
1934 /*
1935 * If we failed fall through to the unwiring section to
1936 * unwire what we had wired so far. 'end' has already
1937 * been adjusted.
1938 */
1939 if (rv)
1940 new_pageable = 1;
1941
1942 /*
1943 * start_entry might have been clipped if we unlocked the
1944 * map and blocked. No matter how clipped it has gotten
1945 * there should be a fragment that is on our start boundary.
1946 */
1947 CLIP_CHECK_BACK(start_entry, start);
1948 }
1949
1950 /*
1951 * Deal with the unwiring case.
1952 */
1953 if (new_pageable) {
1954 /*
1955 * This is the unwiring case. We must first ensure that the
1956 * range to be unwired is really wired down. We know there
1957 * are no holes.
1958 */
1959 entry = start_entry;
1960 while ((entry != &map->header) && (entry->start < end)) {
1961 if ((entry->eflags & MAP_ENTRY_USER_WIRED) == 0) {
1962 rv = KERN_INVALID_ARGUMENT;
1963 goto done;
1964 }
1965 KASSERT(entry->wired_count != 0, ("wired count was 0 with USER_WIRED set! %p", entry));
1966 entry = entry->next;
1967 }
1968
1969 /*
1970 * Now decrement the wiring count for each region. If a region
1971 * becomes completely unwired, unwire its physical pages and
1972 * mappings.
1973 */
b4eddbac
DR
1974 /*
1975 * The map entries are processed in a loop, checking to
1976 * make sure the entry is wired and asserting it has a wired
1977 * count. However, another loop was inserted more-or-less in
1978 * the middle of the unwiring path. This loop picks up the
1979 * "entry" loop variable from the first loop without first
1980 * setting it to start_entry. Naturally, the secound loop
1981 * is never entered and the pages backing the entries are
1982 * never unwired. This can lead to a leak of wired pages.
1983 */
1984 entry = start_entry;
984263bc 1985 while ((entry != &map->header) && (entry->start < end)) {
f2d22ebf
MD
1986 KASSERT(entry->eflags & MAP_ENTRY_USER_WIRED,
1987 ("expected USER_WIRED on entry %p", entry));
984263bc
MD
1988 entry->eflags &= ~MAP_ENTRY_USER_WIRED;
1989 entry->wired_count--;
1990 if (entry->wired_count == 0)
f2d22ebf 1991 vm_fault_unwire(map, entry);
984263bc
MD
1992 entry = entry->next;
1993 }
1994 }
1995done:
a108bf71 1996 vm_map_unclip_range(map, start_entry, start, real_end, &count,
984263bc
MD
1997 MAP_CLIP_NO_HOLES);
1998 map->timestamp++;
1999 vm_map_unlock(map);
a108bf71 2000 vm_map_entry_release(count);
984263bc
MD
2001 return (rv);
2002}
2003
2004/*
cde87949 2005 * vm_map_wire:
984263bc
MD
2006 *
2007 * Sets the pageability of the specified address
2008 * range in the target map. Regions specified
2009 * as not pageable require locked-down physical
2010 * memory and physical page maps.
2011 *
2012 * The map must not be locked, but a reference
2013 * must remain to the map throughout the call.
a108bf71
MD
2014 *
2015 * This function may be called via the zalloc path and must properly
2016 * reserve map entries for kernel_map.
984263bc
MD
2017 */
2018int
e1359933 2019vm_map_wire(vm_map_t map, vm_offset_t start, vm_offset_t real_end, int kmflags)
984263bc
MD
2020{
2021 vm_map_entry_t entry;
2022 vm_map_entry_t start_entry;
2023 vm_offset_t end;
2024 int rv = KERN_SUCCESS;
a108bf71 2025 int count;
984263bc 2026
e1359933 2027 if (kmflags & KM_KRESERVE)
a108bf71 2028 count = vm_map_entry_kreserve(MAP_RESERVE_COUNT);
a108bf71
MD
2029 else
2030 count = vm_map_entry_reserve(MAP_RESERVE_COUNT);
984263bc
MD
2031 vm_map_lock(map);
2032 VM_MAP_RANGE_CHECK(map, start, real_end);
2033 end = real_end;
2034
a108bf71 2035 start_entry = vm_map_clip_range(map, start, end, &count, MAP_CLIP_NO_HOLES);
984263bc
MD
2036 if (start_entry == NULL) {
2037 vm_map_unlock(map);
a108bf71
MD
2038 rv = KERN_INVALID_ADDRESS;
2039 goto failure;
984263bc 2040 }
e1359933 2041 if ((kmflags & KM_PAGEABLE) == 0) {
984263bc
MD
2042 /*
2043 * Wiring.
2044 *
2045 * 1. Holding the write lock, we create any shadow or zero-fill
2046 * objects that need to be created. Then we clip each map
2047 * entry to the region to be wired and increment its wiring
2048 * count. We create objects before clipping the map entries
2049 * to avoid object proliferation.
2050 *
2051 * 2. We downgrade to a read lock, and call vm_fault_wire to
2052 * fault in the pages for any newly wired area (wired_count is
2053 * 1).
2054 *
2055 * Downgrading to a read lock for vm_fault_wire avoids a
2056 * possible deadlock with another process that may have faulted
2057 * on one of the pages to be wired (it would mark the page busy,
2058 * blocking us, then in turn block on the map lock that we
2059 * hold). Because of problems in the recursive lock package,
2060 * we cannot upgrade to a write lock in vm_map_lookup. Thus,
2061 * any actions that require the write lock must be done
2062 * beforehand. Because we keep the read lock on the map, the
2063 * copy-on-write status of the entries we modify here cannot
2064 * change.
2065 */
2066
2067 entry = start_entry;
2068 while ((entry != &map->header) && (entry->start < end)) {
2069 /*
2070 * Trivial case if the entry is already wired
2071 */
2072 if (entry->wired_count) {
2073 entry->wired_count++;
2074 entry = entry->next;
2075 continue;
2076 }
2077
2078 /*
2079 * The entry is being newly wired, we have to setup
2080 * appropriate management structures. A shadow
2081 * object is required for a copy-on-write region,
2082 * or a normal object for a zero-fill region. We
2083 * do not have to do this for entries that point to sub
2084 * maps because we won't hold the lock on the sub map.
2085 */
1b874851 2086 if (entry->maptype != VM_MAPTYPE_SUBMAP) {
984263bc
MD
2087 int copyflag = entry->eflags & MAP_ENTRY_NEEDS_COPY;
2088 if (copyflag &&
2089 ((entry->protection & VM_PROT_WRITE) != 0)) {
53025830 2090 vm_map_entry_shadow(entry);
984263bc
MD
2091 } else if (entry->object.vm_object == NULL &&
2092 !map->system_map) {
53025830 2093 vm_map_entry_allocate_object(entry);
984263bc
MD
2094 }
2095 }
2096
2097 entry->wired_count++;
2098 entry = entry->next;
2099 }
2100
2101 /*
2102 * Pass 2.
2103 */
2104
2105 /*
2106 * HACK HACK HACK HACK
2107 *
2108 * Unlock the map to avoid deadlocks. The in-transit flag
2109 * protects us from most changes but note that
2110 * clipping may still occur. To prevent clipping from
2111 * occuring after the unlock, except for when we are
5fd012e0
MD
2112 * blocking in vm_fault_wire, we must run in a critical
2113 * section, otherwise our accesses to entry->start and
2114 * entry->end could be corrupted. We have to enter the
2115 * critical section prior to unlocking so start_entry does
2116 * not change out from under us at the very beginning of the
2117 * loop.
984263bc
MD
2118 *
2119 * HACK HACK HACK HACK
2120 */
2121
5fd012e0 2122 crit_enter();
984263bc
MD
2123
2124 entry = start_entry;
2125 while (entry != &map->header && entry->start < end) {
2126 /*
2127 * If vm_fault_wire fails for any page we need to undo
2128 * what has been done. We decrement the wiring count
2129 * for those pages which have not yet been wired (now)
2130 * and unwire those that have (later).
2131 */
2132 vm_offset_t save_start = entry->start;
2133 vm_offset_t save_end = entry->end;
2134
2135 if (entry->wired_count == 1)
f2d22ebf 2136 rv = vm_fault_wire(map, entry, FALSE);
984263bc
MD
2137 if (rv) {
2138 CLIP_CHECK_BACK(entry, save_start);
2139 for (;;) {
2140 KASSERT(entry->wired_count == 1, ("wired_count changed unexpectedly"));
2141 entry->wired_count = 0;
2142 if (entry->end == save_end)
2143 break;
2144 entry = entry->next;
2145 KASSERT(entry != &map->header, ("bad entry clip during backout"));
2146 }
2147 end = save_start;
2148 break;
2149 }
2150 CLIP_CHECK_FWD(entry, save_end);
2151 entry = entry->next;
2152 }
5fd012e0 2153 crit_exit();
984263bc 2154
984263bc
MD
2155 /*
2156 * If a failure occured undo everything by falling through
2157 * to the unwiring code. 'end' has already been adjusted
2158 * appropriately.
2159 */
2160 if (rv)
e1359933 2161 kmflags |= KM_PAGEABLE;
984263bc
MD
2162
2163 /*
f2d22ebf
MD
2164 * start_entry is still IN_TRANSITION but may have been
2165 * clipped since vm_fault_wire() unlocks and relocks the
2166 * map. No matter how clipped it has gotten there should
2167 * be a fragment that is on our start boundary.
984263bc
MD
2168 */
2169 CLIP_CHECK_BACK(start_entry, start);
2170 }
2171
e1359933 2172 if (kmflags & KM_PAGEABLE) {
984263bc
MD
2173 /*
2174 * This is the unwiring case. We must first ensure that the
2175 * range to be unwired is really wired down. We know there
2176 * are no holes.
2177 */
2178 entry = start_entry;
2179 while ((entry != &map->header) && (entry->start < end)) {
2180 if (entry->wired_count == 0) {
2181 rv = KERN_INVALID_ARGUMENT;
2182 goto done;
2183 }
2184 entry = entry->next;
2185 }
2186
2187 /*
2188 * Now decrement the wiring count for each region. If a region
2189 * becomes completely unwired, unwire its physical pages and
2190 * mappings.
2191 */
2192 entry = start_entry;
2193 while ((entry != &map->header) && (entry->start < end)) {
2194 entry->wired_count--;
2195 if (entry->wired_count == 0)
f2d22ebf 2196 vm_fault_unwire(map, entry);
984263bc
MD
2197 entry = entry->next;
2198 }
2199 }
2200done:
a108bf71 2201 vm_map_unclip_range(map, start_entry, start, real_end, &count,
984263bc
MD
2202 MAP_CLIP_NO_HOLES);
2203 map->timestamp++;
2204 vm_map_unlock(map);
a108bf71 2205failure:
e1359933 2206 if (kmflags & KM_KRESERVE)
a108bf71 2207 vm_map_entry_krelease(count);
a108bf71
MD
2208 else
2209 vm_map_entry_release(count);
984263bc
MD
2210 return (rv);
2211}
2212
a108bf71
MD
2213/*
2214 * vm_map_set_wired_quick()
2215 *
2216 * Mark a newly allocated address range as wired but do not fault in
2217 * the pages. The caller is expected to load the pages into the object.
2218 *
2219 * The map must be locked on entry and will remain locked on return.
2220 */
2221void
2222vm_map_set_wired_quick(vm_map_t map, vm_offset_t addr, vm_size_t size, int *countp)
2223{
2224 vm_map_entry_t scan;
2225 vm_map_entry_t entry;
2226
2227 entry = vm_map_clip_range(map, addr, addr + size, countp, MAP_CLIP_NO_HOLES);
2228 for (scan = entry; scan != &map->header && scan->start < addr + size; scan = scan->next) {
2229 KKASSERT(entry->wired_count == 0);
2230 entry->wired_count = 1;
2231 }
2232 vm_map_unclip_range(map, entry, addr, addr + size, countp, MAP_CLIP_NO_HOLES);
2233}
2234
984263bc
MD
2235/*
2236 * vm_map_clean
2237 *
2238 * Push any dirty cached pages in the address range to their pager.
2239 * If syncio is TRUE, dirty pages are written synchronously.
2240 * If invalidate is TRUE, any cached pages are freed as well.
2241 *
2242 * Returns an error if any part of the specified range is not mapped.
2243 */
2244int
57e43348
MD
2245vm_map_clean(vm_map_t map, vm_offset_t start, vm_offset_t end, boolean_t syncio,
2246 boolean_t invalidate)
984263bc
MD
2247{
2248 vm_map_entry_t current;
2249 vm_map_entry_t entry;
2250 vm_size_t size;
2251 vm_object_t object;
2252 vm_ooffset_t offset;
2253
2254 vm_map_lock_read(map);
2255 VM_MAP_RANGE_CHECK(map, start, end);
2256 if (!vm_map_lookup_entry(map, start, &entry)) {
2257 vm_map_unlock_read(map);
2258 return (KERN_INVALID_ADDRESS);
2259 }
2260 /*
2261 * Make a first pass to check for holes.
2262 */
2263 for (current = entry; current->start < end; current = current->next) {
1b874851 2264 if (current->maptype == VM_MAPTYPE_SUBMAP) {
984263bc
MD
2265 vm_map_unlock_read(map);
2266 return (KERN_INVALID_ARGUMENT);
2267 }
2268 if (end > current->end &&
2269 (current->next == &map->header ||
2270 current->end != current->next->start)) {
2271 vm_map_unlock_read(map);
2272 return (KERN_INVALID_ADDRESS);
2273 }
2274 }
2275
2276 if (invalidate)
2277 pmap_remove(vm_map_pmap(map), start, end);
2278 /*
2279 * Make a second pass, cleaning/uncaching pages from the indicated
2280 * objects as we go.
2281 */
2282 for (current = entry; current->start < end; current = current->next) {
2283 offset = current->offset + (start - current->start);
2284 size = (end <= current->end ? end : current->end) - start;
1b874851 2285 if (current->maptype == VM_MAPTYPE_SUBMAP) {
984263bc
MD
2286 vm_map_t smap;
2287 vm_map_entry_t tentry;
2288 vm_size_t tsize;
2289
2290 smap = current->object.sub_map;
2291 vm_map_lock_read(smap);
418ff780 2292 vm_map_lookup_entry(smap, offset, &tentry);
984263bc
MD
2293 tsize = tentry->end - offset;
2294 if (tsize < size)
2295 size = tsize;
2296 object = tentry->object.vm_object;
2297 offset = tentry->offset + (offset - tentry->start);
2298 vm_map_unlock_read(smap);
2299 } else {
2300 object = current->object.vm_object;
2301 }
2302 /*
2303 * Note that there is absolutely no sense in writing out
2304 * anonymous objects, so we track down the vnode object
2305 * to write out.
2306 * We invalidate (remove) all pages from the address space
2307 * anyway, for semantic correctness.
2308 *
2309 * note: certain anonymous maps, such as MAP_NOSYNC maps,
2310 * may start out with a NULL object.
2311 */
2312 while (object && object->backing_object) {
984263bc 2313 offset += object->backing_object_offset;
7cad6903 2314 object = object->backing_object;
984263bc
MD
2315 if (object->size < OFF_TO_IDX( offset + size))
2316 size = IDX_TO_OFF(object->size) - offset;
2317 }
2318 if (object && (object->type == OBJT_VNODE) &&
2319 (current->protection & VM_PROT_WRITE)) {
2320 /*
2321 * Flush pages if writing is allowed, invalidate them
2322 * if invalidation requested. Pages undergoing I/O
2323 * will be ignored by vm_object_page_remove().
2324 *
2325 * We cannot lock the vnode and then wait for paging
2326 * to complete without deadlocking against vm_fault.
2327 * Instead we simply call vm_object_page_remove() and
2328 * allow it to block internally on a page-by-page
2329 * basis when it encounters pages undergoing async
2330 * I/O.
2331 */
2332 int flags;
2333
2334 vm_object_reference(object);
ca466bae 2335 vn_lock(object->handle, LK_EXCLUSIVE | LK_RETRY);
984263bc
MD
2336 flags = (syncio || invalidate) ? OBJPC_SYNC : 0;
2337 flags |= invalidate ? OBJPC_INVAL : 0;
1b874851
MD
2338
2339 /*
2340 * When operating on a virtual page table just
2341 * flush the whole object. XXX we probably ought
2342 * to
2343 */
2344 switch(current->maptype) {
2345 case VM_MAPTYPE_NORMAL:
2346 vm_object_page_clean(object,
2347 OFF_TO_IDX(offset),
2348 OFF_TO_IDX(offset + size + PAGE_MASK),
2349 flags);
2350 break;
2351 case VM_MAPTYPE_VPAGETABLE:
2352 vm_object_page_clean(object, 0, 0, flags);
2353 break;
2354 }
a11aaa81 2355 vn_unlock(((struct vnode *)object->handle));
984263bc
MD
2356 vm_object_deallocate(object);
2357 }
2358 if (object && invalidate &&
2359 ((object->type == OBJT_VNODE) ||
2360 (object->type == OBJT_DEVICE))) {
2f1821ca
MD
2361 int clean_only =
2362 (object->type == OBJT_DEVICE) ? FALSE : TRUE;
984263bc 2363 vm_object_reference(object);
1b874851
MD
2364 switch(current->maptype) {
2365 case VM_MAPTYPE_NORMAL:
2366 vm_object_page_remove(object,
2367 OFF_TO_IDX(offset),
2368 OFF_TO_IDX(offset + size + PAGE_MASK),
2369 clean_only);
2370 break;
2371 case VM_MAPTYPE_VPAGETABLE:
2372 vm_object_page_remove(object, 0, 0, clean_only);
2373 break;
2374 }
984263bc
MD
2375 vm_object_deallocate(object);
2376 }
2377 start += size;
2378 }
2379
2380 vm_map_unlock_read(map);
2381 return (KERN_SUCCESS);
2382}
2383
2384/*
2385 * vm_map_entry_unwire: [ internal use only ]
2386 *
2387 * Make the region specified by this entry pageable.
2388 *
2389 * The map in question should be locked.
2390 * [This is the reason for this routine's existence.]
2391 */
2392static void
a108bf71 2393vm_map_entry_unwire(vm_map_t map, vm_map_entry_t entry)
984263bc 2394{
f2d22ebf 2395 entry->eflags &= ~MAP_ENTRY_USER_WIRED;
984263bc 2396 entry->wired_count = 0;
f2d22ebf 2397 vm_fault_unwire(map, entry);
984263bc
MD
2398}
2399
2400/*
2401 * vm_map_entry_delete: [ internal use only ]
2402 *
2403 * Deallocate the given entry from the target map.
2404 */
2405static void
a108bf71 2406vm_map_entry_delete(vm_map_t map, vm_map_entry_t entry, int *countp)
984263bc
MD
2407{
2408 vm_map_entry_unlink(map, entry);
2409 map->size -= entry->end - entry->start;
2410
1b874851
MD
2411 switch(entry->maptype) {
2412 case VM_MAPTYPE_NORMAL:
2413 case VM_MAPTYPE_VPAGETABLE:
984263bc 2414 vm_object_deallocate(entry->object.vm_object);
1b874851
MD
2415 break;
2416 default:
2417 break;
984263bc
MD
2418 }
2419
a108bf71 2420 vm_map_entry_dispose(map, entry, countp);
984263bc
MD
2421}
2422
2423/*
2424 * vm_map_delete: [ internal use only ]
2425 *
2426 * Deallocates the given address range from the target
2427 * map.
2428 */
2429int
a108bf71 2430vm_map_delete(vm_map_t map, vm_offset_t start, vm_offset_t end, int *countp)
984263bc
MD
2431{
2432 vm_object_t object;
2433 vm_map_entry_t entry;
2434 vm_map_entry_t first_entry;
2435
686dbf64 2436again:
984263bc 2437 /*
686dbf64
MD
2438 * Find the start of the region, and clip it. Set entry to point
2439 * at the first record containing the requested address or, if no
2440 * such record exists, the next record with a greater address. The
2441 * loop will run from this point until a record beyond the termination
2442 * address is encountered.
2443 *
2444 * map->hint must be adjusted to not point to anything we delete,
2445 * so set it to the entry prior to the one being deleted.
2446 *
2447 * GGG see other GGG comment.
984263bc 2448 */
686dbf64 2449 if (vm_map_lookup_entry(map, start, &first_entry)) {
984263bc 2450 entry = first_entry;
a108bf71 2451 vm_map_clip_start(map, entry, start, countp);
686dbf64
MD
2452 map->hint = entry->prev; /* possible problem XXX */
2453 } else {
2454 map->hint = first_entry; /* possible problem XXX */
2455 entry = first_entry->next;
984263bc
MD
2456 }
2457
2458 /*
686dbf64
MD
2459 * If a hole opens up prior to the current first_free then
2460 * adjust first_free. As with map->hint, map->first_free
2461 * cannot be left set to anything we might delete.
984263bc 2462 */
984263bc
MD
2463 if (entry == &map->header) {
2464 map->first_free = &map->header;
2465 } else if (map->first_free->start >= start) {
2466 map->first_free = entry->prev;
2467 }
2468
2469 /*
2470 * Step through all entries in this region
2471 */
2472
2473 while ((entry != &map->header) && (entry->start < end)) {
2474 vm_map_entry_t next;
2475 vm_offset_t s, e;
2476 vm_pindex_t offidxstart, offidxend, count;
2477
2478 /*
2479 * If we hit an in-transition entry we have to sleep and
2480 * retry. It's easier (and not really slower) to just retry
2481 * since this case occurs so rarely and the hint is already
2482 * pointing at the right place. We have to reset the
2483 * start offset so as not to accidently delete an entry
2484 * another process just created in vacated space.
2485 */
2486 if (entry->eflags & MAP_ENTRY_IN_TRANSITION) {
2487 entry->eflags |= MAP_ENTRY_NEEDS_WAKEUP;
2488 start = entry->start;
12e4aaff
MD
2489 ++mycpu->gd_cnt.v_intrans_coll;
2490 ++mycpu->gd_cnt.v_intrans_wait;
984263bc
MD
2491 vm_map_transition_wait(map);
2492 goto again;
2493 }
a108bf71 2494 vm_map_clip_end(map, entry, end, countp);
984263bc
MD
2495
2496 s = entry->start;
2497 e = entry->end;
2498 next = entry->next;
2499
2500 offidxstart = OFF_TO_IDX(entry->offset);
2501 count = OFF_TO_IDX(e - s);
2502 object = entry->object.vm_object;
2503
2504 /*
2505 * Unwire before removing addresses from the pmap; otherwise,
2506 * unwiring will put the entries back in the pmap.
2507 */
f2d22ebf 2508 if (entry->wired_count != 0)
984263bc 2509 vm_map_entry_unwire(map, entry);
984263bc
MD
2510
2511 offidxend = offidxstart + count;
2512
c439ad8f 2513 if (object == &kernel_object) {
984263bc
MD
2514 vm_object_page_remove(object, offidxstart, offidxend, FALSE);
2515 } else {
2516 pmap_remove(map->pmap, s, e);
2517 if (object != NULL &&
2518 object->ref_count != 1 &&
2519 (object->flags & (OBJ_NOSPLIT|OBJ_ONEMAPPING)) == OBJ_ONEMAPPING &&
2520 (object->type == OBJT_DEFAULT || object->type == OBJT_SWAP)) {
2521 vm_object_collapse(object);
2522 vm_object_page_remove(object, offidxstart, offidxend, FALSE);
2523 if (object->type == OBJT_SWAP) {
2524 swap_pager_freespace(object, offidxstart, count);
2525 }
2526 if (offidxend >= object->size &&
2527 offidxstart < object->size) {
2528 object->size = offidxstart;
2529 }
2530 }
2531 }
2532
2533 /*
2534 * Delete the entry (which may delete the object) only after
2535 * removing all pmap entries pointing to its pages.
2536 * (Otherwise, its page frames may be reallocated, and any
2537 * modify bits will be set in the wrong object!)
2538 */
a108bf71 2539 vm_map_entry_delete(map, entry, countp);
984263bc
MD
2540 entry = next;
2541 }
2542 return (KERN_SUCCESS);
2543}
2544
2545/*
2546 * vm_map_remove:
2547 *
2548 * Remove the given address range from the target map.
2549 * This is the exported form of vm_map_delete.
2550 */
2551int
a108bf71 2552vm_map_remove(vm_map_t map, vm_offset_t start, vm_offset_t end)
984263bc 2553{
03aa8d99 2554 int result;
a108bf71 2555 int count;
984263bc 2556
a108bf71 2557 count = vm_map_entry_reserve(MAP_RESERVE_COUNT);
984263bc
MD
2558 vm_map_lock(map);
2559 VM_MAP_RANGE_CHECK(map, start, end);
a108bf71 2560 result = vm_map_delete(map, start, end, &count);
984263bc 2561 vm_map_unlock(map);
a108bf71 2562 vm_map_entry_release(count);
984263bc 2563
984263bc
MD
2564 return (result);
2565}
2566
2567/*
2568 * vm_map_check_protection:
2569 *
2570 * Assert that the target map allows the specified
2571 * privilege on the entire address region given.
2572 * The entire region must be allocated.
2573 */
2574boolean_t
2575vm_map_check_protection(vm_map_t map, vm_offset_t start, vm_offset_t end,
2576 vm_prot_t protection)
2577{
2578 vm_map_entry_t entry;
2579 vm_map_entry_t tmp_entry;
2580
2581 if (!vm_map_lookup_entry(map, start, &tmp_entry)) {
2582 return (FALSE);
2583 }
2584 entry = tmp_entry;
2585
2586 while (start < end) {
2587 if (entry == &map->header) {
2588 return (FALSE);
2589 }
2590 /*
2591 * No holes allowed!
2592 */
2593
2594 if (start < entry->start) {
2595 return (FALSE);
2596 }
2597 /*
2598 * Check protection associated with entry.
2599 */
2600
2601 if ((entry->protection & protection) != protection) {
2602 return (FALSE);
2603 }
2604 /* go to next entry */
2605
2606 start = entry->end;
2607 entry = entry->next;
2608 }
2609 return (TRUE);
2610}
2611
2612/*
2613 * Split the pages in a map entry into a new object. This affords
2614 * easier removal of unused pages, and keeps object inheritance from
2615 * being a negative impact on memory usage.
2616 */
2617static void
a108bf71 2618vm_map_split(vm_map_entry_t entry)
984263bc
MD
2619{
2620 vm_page_t m;
2621 vm_object_t orig_object, new_object, source;
2622 vm_offset_t s, e;
2623 vm_pindex_t offidxstart, offidxend, idx;
2624 vm_size_t size;
2625 vm_ooffset_t offset;
2626
2627 orig_object = entry->object.vm_object;
2628 if (orig_object->type != OBJT_DEFAULT && orig_object->type != OBJT_SWAP)
2629 return;
2630 if (orig_object->ref_count <= 1)
2631 return;
2632
2633 offset = entry->offset;
2634 s = entry->start;
2635 e = entry->end;
2636
2637 offidxstart = OFF_TO_IDX(offset);
2638 offidxend = offidxstart + OFF_TO_IDX(e - s);
2639 size = offidxend - offidxstart;
2640
57f7b636
MD
2641 new_object = vm_pager_allocate(orig_object->type, NULL,
2642 IDX_TO_OFF(size), VM_PROT_ALL, 0);
984263bc
MD
2643 if (new_object == NULL)
2644 return;
2645
2646 source = orig_object->backing_object;
2647 if (source != NULL) {
2648 vm_object_reference(source); /* Referenced by new_object */
2649 LIST_INSERT_HEAD(&source->shadow_head,
2650 new_object, shadow_list);
2651 vm_object_clear_flag(source, OBJ_ONEMAPPING);
2652 new_object->backing_object_offset =
2653 orig_object->backing_object_offset + IDX_TO_OFF(offidxstart);
2654 new_object->backing_object = source;
2655 source->shadow_count++;
2656 source->generation++;
2657 }
2658
2659 for (idx = 0; idx < size; idx++) {
2660 vm_page_t m;
2661
06ecca5a 2662 /*
5fd012e0 2663 * A critical section is required to avoid a race between
06ecca5a
MD
2664 * the lookup and an interrupt/unbusy/free and our busy
2665 * check.
2666 */
5fd012e0 2667 crit_enter();
984263bc
MD
2668 retry:
2669 m = vm_page_lookup(orig_object, offidxstart + idx);
06ecca5a 2670 if (m == NULL) {
5fd012e0 2671 crit_exit();
984263bc 2672 continue;
06ecca5a 2673 }
984263bc
MD
2674
2675 /*
2676 * We must wait for pending I/O to complete before we can
2677 * rename the page.
2678 *
2679 * We do not have to VM_PROT_NONE the page as mappings should
2680 * not be changed by this operation.
2681 */
2682 if (vm_page_sleep_busy(m, TRUE, "spltwt"))
2683 goto retry;
984263bc
MD
2684 vm_page_busy(m);
2685 vm_page_rename(m, new_object, idx);
2686 /* page automatically made dirty by rename and cache handled */
2687 vm_page_busy(m);
5fd012e0 2688 crit_exit();
984263bc
MD
2689 }
2690
2691 if (orig_object->type == OBJT_SWAP) {
2692 vm_object_pip_add(orig_object, 1);
2693 /*
2694 * copy orig_object pages into new_object
2695 * and destroy unneeded pages in
2696 * shadow object.
2697 */
2698 swap_pager_copy(orig_object, new_object, offidxstart, 0);
2699 vm_object_pip_wakeup(orig_object);
2700 }
2701
06ecca5a
MD
2702 /*
2703 * Wakeup the pages we played with. No spl protection is needed
2704 * for a simple wakeup.
2705 */
984263bc
MD
2706 for (idx = 0; idx < size; idx++) {
2707 m = vm_page_lookup(new_object, idx);
06ecca5a 2708 if (m)
984263bc 2709 vm_page_wakeup(m);
984263bc
MD
2710 }
2711
2712 entry->object.vm_object = new_object;
2713 entry->offset = 0LL;
2714 vm_object_deallocate(orig_object);
2715}
2716
2717/*
2718 * vm_map_copy_entry:
2719 *
2720 * Copies the contents of the source entry to the destination
2721 * entry. The entries *must* be aligned properly.
2722 */
2723static void
a108bf71
MD
2724vm_map_copy_entry(vm_map_t src_map, vm_map_t dst_map,
2725 vm_map_entry_t src_entry, vm_map_entry_t dst_entry)
984263bc
MD
2726{
2727 vm_object_t src_object;
2728
1b874851
MD
2729 if (dst_entry->maptype == VM_MAPTYPE_SUBMAP)
2730 return;
2731 if (src_entry->maptype == VM_MAPTYPE_SUBMAP)
984263bc
MD
2732 return;
2733
2734 if (src_entry->wired_count == 0) {
984263bc
MD
2735 /*
2736 * If the source entry is marked needs_copy, it is already
2737 * write-protected.
2738 */
2739 if ((src_entry->eflags & MAP_ENTRY_NEEDS_COPY) == 0) {
2740 pmap_protect(src_map->pmap,
2741 src_entry->start,
2742 src_entry->end,
2743 src_entry->protection & ~VM_PROT_WRITE);
2744 }
2745
2746 /*
2747 * Make a copy of the object.
2748 */
2749 if ((src_object = src_entry->object.vm_object) != NULL) {
984263bc
MD
2750 if ((src_object->handle == NULL) &&
2751 (src_object->type == OBJT_DEFAULT ||
2752 src_object->type == OBJT_SWAP)) {
2753 vm_object_collapse(src_object);
2754 if ((src_object->flags & (OBJ_NOSPLIT|OBJ_ONEMAPPING)) == OBJ_ONEMAPPING) {
2755 vm_map_split(src_entry);
2756 src_object = src_entry->object.vm_object;
2757 }
2758 }
2759
2760 vm_object_reference(src_object);
2761 vm_object_clear_flag(src_object, OBJ_ONEMAPPING);
2762 dst_entry->object.vm_object = src_object;
2763 src_entry->eflags |= (MAP_ENTRY_COW|MAP_ENTRY_NEEDS_COPY);
2764 dst_entry->eflags |= (MAP_ENTRY_COW|MAP_ENTRY_NEEDS_COPY);
2765 dst_entry->offset = src_entry->offset;
2766 } else {
2767 dst_entry->object.vm_object = NULL;
2768 dst_entry->offset = 0;
2769 }
2770
2771 pmap_copy(dst_map->pmap, src_map->pmap, dst_entry->start,
2772 dst_entry->end - dst_entry->start, src_entry->start);
2773 } else {
2774 /*
2775 * Of course, wired down pages can't be set copy-on-write.
2776 * Cause wired pages to be copied into the new map by
2777 * simulating faults (the new pages are pageable)
2778 */
2779 vm_fault_copy_entry(dst_map, src_map, dst_entry, src_entry);
2780 }
2781}
2782
2783/*
2784 * vmspace_fork:
2785 * Create a new process vmspace structure and vm_map
2786 * based on those of an existing process. The new map
2787 * is based on the old map, according to the inheritance
2788 * values on the regions in that map.
2789 *
2790 * The source map must not be locked.
2791 */
2792struct vmspace *
a108bf71 2793vmspace_fork(struct vmspace *vm1)
984263bc
MD
2794{
2795 struct vmspace *vm2;
2796 vm_map_t old_map = &vm1->vm_map;
2797 vm_map_t new_map;
2798 vm_map_entry_t old_entry;
2799 vm_map_entry_t new_entry;
2800 vm_object_t object;
a108bf71 2801 int count;
984263bc
MD
2802
2803 vm_map_lock(old_map);
2804 old_map->infork = 1;
2805
239b4df9
MD
2806 /*
2807 * XXX Note: upcalls are not copied.
2808 */
984263bc
MD
2809 vm2 = vmspace_alloc(old_map->min_offset, old_map->max_offset);
2810 bcopy(&vm1->vm_startcopy, &vm2->vm_startcopy,
239b4df9 2811 (caddr_t)&vm1->vm_endcopy - (caddr_t)&vm1->vm_startcopy);
984263bc
MD
2812 new_map = &vm2->vm_map; /* XXX */
2813 new_map->timestamp = 1;
2814
a108bf71 2815 count = 0;
984263bc 2816 old_entry = old_map->header.next;
a108bf71
MD
2817 while (old_entry != &old_map->header) {
2818 ++count;
2819 old_entry = old_entry->next;
2820 }
984263bc 2821
a108bf71
MD
2822 count = vm_map_entry_reserve(count + MAP_RESERVE_COUNT);
2823
2824 old_entry = old_map->header.next;
984263bc 2825 while (old_entry != &old_map->header) {
1b874851 2826 if (old_entry->maptype == VM_MAPTYPE_SUBMAP)
984263bc
MD
2827 panic("vm_map_fork: encountered a submap");
2828
2829 switch (old_entry->inheritance) {
2830 case VM_INHERIT_NONE:
2831 break;
2832
2833 case VM_INHERIT_SHARE:
2834 /*
1b874851
MD
2835 * Clone the entry, creating the shared object if
2836 * necessary.
984263bc
MD
2837 */
2838 object = old_entry->object.vm_object;
2839 if (object == NULL) {
53025830
MD
2840 vm_map_entry_allocate_object(old_entry);
2841 object = old_entry->object.vm_object;
984263bc
MD
2842 }
2843
2844 /*
53025830 2845 * Add the reference before calling vm_map_entry_shadow
984263bc
MD
2846 * to insure that a shadow object is created.
2847 */
2848 vm_object_reference(object);
2849 if (old_entry->eflags & MAP_ENTRY_NEEDS_COPY) {
53025830 2850 vm_map_entry_shadow(old_entry);
984263bc
MD
2851 /* Transfer the second reference too. */
2852 vm_object_reference(
2853 old_entry->object.vm_object);
2854 vm_object_deallocate(object);
2855 object = old_entry->object.vm_object;
2856 }
2857 vm_object_clear_flag(object, OBJ_ONEMAPPING);
2858
2859 /*
2860 * Clone the entry, referencing the shared object.
2861 */
a108bf71 2862 new_entry = vm_map_entry_create(new_map, &count);
984263bc
MD
2863 *new_entry = *old_entry;
2864 new_entry->eflags &= ~MAP_ENTRY_USER_WIRED;
2865 new_entry->wired_count = 0;
2866
2867 /*
2868 * Insert the entry into the new map -- we know we're
2869 * inserting at the end of the new map.
2870 */
2871
2872 vm_map_entry_link(new_map, new_map->header.prev,
2873 new_entry);
2874
2875 /*
2876 * Update the physical map
2877 */
2878
2879 pmap_copy(new_map->pmap, old_map->pmap,
2880 new_entry->start,
2881 (old_entry->end - old_entry->start),
2882 old_entry->start);
2883 break;
2884
2885 case VM_INHERIT_COPY:
2886 /*
2887 * Clone the entry and link into the map.
2888 */
a108bf71 2889 new_entry = vm_map_entry_create(new_map, &count);
984263bc
MD
2890 *new_entry = *old_entry;
2891 new_entry->eflags &= ~MAP_ENTRY_USER_WIRED;
2892 new_entry->wired_count = 0;
2893 new_entry->object.vm_object = NULL;
2894 vm_map_entry_link(new_map, new_map->header.prev,
2895 new_entry);
2896 vm_map_copy_entry(old_map, new_map, old_entry,
2897 new_entry);
2898 break;
2899 }
2900 old_entry = old_entry->next;
2901 }
2902
2903 new_map->size = old_map->size;
2904 old_map->infork = 0;
2905 vm_map_unlock(old_map);
a108bf71 2906 vm_map_entry_release(count);
984263bc
MD
2907
2908 return (vm2);
2909}
2910
2911int
2912vm_map_stack (vm_map_t map, vm_offset_t addrbos, vm_size_t max_ssize,
2913 vm_prot_t prot, vm_prot_t max, int cow)
2914{
2915 vm_map_entry_t prev_entry;
2916 vm_map_entry_t new_stack_entry;
2917 vm_size_t init_ssize;
2918 int rv;
a108bf71 2919 int count;
984263bc 2920
88181b08 2921 if (VM_MIN_USER_ADDRESS > 0 && addrbos < VM_MIN_USER_ADDRESS)
984263bc
MD
2922 return (KERN_NO_SPACE);
2923
2924 if (max_ssize < sgrowsiz)
2925 init_ssize = max_ssize;
2926 else
2927 init_ssize = sgrowsiz;
2928
a108bf71 2929 count = vm_map_entry_reserve(MAP_RESERVE_COUNT);
984263bc
MD
2930 vm_map_lock(map);
2931
2932 /* If addr is already mapped, no go */
2933 if (vm_map_lookup_entry(map, addrbos, &prev_entry)) {
2934 vm_map_unlock(map);
a108bf71 2935 vm_map_entry_release(count);
984263bc
MD
2936 return (KERN_NO_SPACE);
2937 }
2938
2939 /* If we would blow our VMEM resource limit, no go */
2940 if (map->size + init_ssize >
2941 curproc->p_rlimit[RLIMIT_VMEM].rlim_cur) {
2942 vm_map_unlock(map);
a108bf71 2943 vm_map_entry_release(count);
984263bc
MD
2944 return (KERN_NO_SPACE);
2945 }
2946
2947 /* If we can't accomodate max_ssize in the current mapping,
2948 * no go. However, we need to be aware that subsequent user
2949 * mappings might map into the space we have reserved for
2950 * stack, and currently this space is not protected.
2951 *
2952 * Hopefully we will at least detect this condition
2953 * when we try to grow the stack.
2954 */
2955 if ((prev_entry->next != &map->header) &&
2956 (prev_entry->next->start < addrbos + max_ssize)) {
2957 vm_map_unlock(map);
a108bf71 2958 vm_map_entry_release(count);
984263bc
MD
2959 return (KERN_NO_SPACE);
2960 }
2961
2962 /* We initially map a stack of only init_ssize. We will
2963 * grow as needed later. Since this is to be a grow
2964 * down stack, we map at the top of the range.
2965 *
2966 * Note: we would normally expect prot and max to be
2967 * VM_PROT_ALL, and cow to be 0. Possibly we should
2968 * eliminate these as input parameters, and just
2969 * pass these values here in the insert call.
2970 */
a108bf71
MD
2971 rv = vm_map_insert(map, &count,
2972 NULL, 0, addrbos + max_ssize - init_ssize,
1b874851
MD
2973 addrbos + max_ssize,
2974 VM_MAPTYPE_NORMAL,
2975 prot, max,
2976 cow);
984263bc
MD
2977
2978 /* Now set the avail_ssize amount */
517e1666 2979 if (rv == KERN_SUCCESS) {
984263bc 2980 if (prev_entry != &map->header)
a108bf71 2981 vm_map_clip_end(map, prev_entry, addrbos + max_ssize - init_ssize, &count);
984263bc
MD
2982 new_stack_entry = prev_entry->next;
2983 if (new_stack_entry->end != addrbos + max_ssize ||
2984 new_stack_entry->start != addrbos + max_ssize - init_ssize)
2985 panic ("Bad entry start/end for new stack entry");
2986 else
afeabdca 2987 new_stack_entry->aux.avail_ssize = max_ssize - init_ssize;
984263bc
MD
2988 }
2989
2990 vm_map_unlock(map);
a108bf71 2991 vm_map_entry_release(count);
984263bc
MD
2992 return (rv);
2993}
2994
2995/* Attempts to grow a vm stack entry. Returns KERN_SUCCESS if the
2996 * desired address is already mapped, or if we successfully grow
2997 * the stack. Also returns KERN_SUCCESS if addr is outside the
2998 * stack range (this is strange, but preserves compatibility with
2999 * the grow function in vm_machdep.c).
3000 */
3001int
3002vm_map_growstack (struct proc *p, vm_offset_t addr)
3003{
3004 vm_map_entry_t prev_entry;
3005 vm_map_entry_t stack_entry;
3006 vm_map_entry_t new_stack_entry;
3007 struct vmspace *vm = p->p_vmspace;
3008 vm_map_t map = &vm->vm_map;
3009 vm_offset_t end;
a108bf71
MD
3010 int grow_amount;
3011 int rv = KERN_SUCCESS;
3012 int is_procstack;
3013 int use_read_lock = 1;
3014 int count;
984263bc 3015
a108bf71 3016 count = vm_map_entry_reserve(MAP_RESERVE_COUNT);
984263bc
MD
3017Retry:
3018 if (use_read_lock)
3019 vm_map_lock_read(map);
3020 else
3021 vm_map_lock(map);
3022
3023 /* If addr is already in the entry range, no need to grow.*/
3024 if (vm_map_lookup_entry(map, addr, &prev_entry))
3025 goto done;
3026
3027 if ((stack_entry = prev_entry->next) == &map->header)
3028 goto done;
3029 if (prev_entry == &map->header)
afeabdca 3030 end = stack_entry->start - stack_entry->aux.avail_ssize;
984263bc
MD
3031 else
3032 end = prev_entry->end;
3033
3034 /* This next test mimics the old grow function in vm_machdep.c.
3035 * It really doesn't quite make sense, but we do it anyway
3036 * for compatibility.
3037 *
3038 * If not growable stack, return success. This signals the
3039 * caller to proceed as he would normally with normal vm.
3040 */
afeabdca 3041 if (stack_entry->aux.avail_ssize < 1 ||
984263bc 3042 addr >= stack_entry->start ||
afeabdca 3043 addr < stack_entry->start - stack_entry->aux.avail_ssize) {
984263bc
MD
3044 goto done;
3045 }
3046
3047 /* Find the minimum grow amount */
3048 grow_amount = roundup (stack_entry->start - addr, PAGE_SIZE);
afeabdca 3049 if (grow_amount > stack_entry->aux.avail_ssize) {
984263bc
MD
3050 rv = KERN_NO_SPACE;
3051 goto done;
3052 }
3053
3054 /* If there is no longer enough space between the entries
3055 * nogo, and adjust the available space. Note: this
3056 * should only happen if the user has mapped into the
3057 * stack area after the stack was created, and is
3058 * probably an error.
3059 *
3060 * This also effectively destroys any guard page the user
3061 * might have intended by limiting the stack size.
3062 */
3063 if (grow_amount > stack_entry->start - end) {
3064 if (use_read_lock && vm_map_lock_upgrade(map)) {
3065 use_read_lock = 0;
3066 goto Retry;
3067 }
3068 use_read_lock = 0;
afeabdca 3069 stack_entry->aux.avail_ssize = stack_entry->start - end;
984263bc
MD
3070 rv = KERN_NO_SPACE;
3071 goto done;
3072 }
3073
3074 is_procstack = addr >= (vm_offset_t)vm->vm_maxsaddr;
3075
3076 /* If this is the main process stack, see if we're over the
3077 * stack limit.
3078 */
3079 if (is_procstack && (ctob(vm->vm_ssize) + grow_amount >
3080 p->p_rlimit[RLIMIT_STACK].rlim_cur)) {
3081 rv = KERN_NO_SPACE;
3082 goto done;
3083 }
3084
3085 /* Round up the grow amount modulo SGROWSIZ */
3086 grow_amount = roundup (grow_amount, sgrowsiz);
afeabdca
MD
3087 if (grow_amount > stack_entry->aux.avail_ssize) {
3088 grow_amount = stack_entry->aux.avail_ssize;
984263bc
MD
3089 }
3090 if (is_procstack && (ctob(vm->vm_ssize) + grow_amount >
3091 p->p_rlimit[RLIMIT_STACK].rlim_cur)) {
3092 grow_amount = p->p_rlimit[RLIMIT_STACK].rlim_cur -
3093 ctob(vm->vm_ssize);
3094 }
3095
3096 /* If we would blow our VMEM resource limit, no go */
be77b5f9 3097 if (map->size + grow_amount > p->p_rlimit[RLIMIT_VMEM].rlim_cur) {
984263bc
MD
3098 rv = KERN_NO_SPACE;
3099 goto done;
3100 }
3101
3102 if (use_read_lock && vm_map_lock_upgrade(map)) {
3103 use_read_lock = 0;
3104 goto Retry;
3105 }
3106 use_read_lock = 0;
3107
3108 /* Get the preliminary new entry start value */
3109 addr = stack_entry->start - grow_amount;
3110
3111 /* If this puts us into the previous entry, cut back our growth
3112 * to the available space. Also, see the note above.
3113 */
3114 if (addr < end) {
afeabdca 3115 stack_entry->aux.avail_ssize = stack_entry->start - end;
984263bc
MD
3116 addr = end;
3117 }
3118
a108bf71
MD
3119 rv = vm_map_insert(map, &count,
3120 NULL, 0, addr, stack_entry->start,
1b874851
MD
3121 VM_MAPTYPE_NORMAL,
3122 VM_PROT_ALL, VM_PROT_ALL,
984263bc
MD
3123 0);
3124
3125 /* Adjust the available stack space by the amount we grew. */
3126 if (rv == KERN_SUCCESS) {
3127 if (prev_entry != &map->header)
a108bf71 3128 vm_map_clip_end(map, prev_entry, addr, &count);
984263bc
MD
3129 new_stack_entry = prev_entry->next;
3130 if (new_stack_entry->end != stack_entry->start ||
3131 new_stack_entry->start != addr)
3132 panic ("Bad stack grow start/end in new stack entry");
3133 else {
afeabdca
MD
3134 new_stack_entry->aux.avail_ssize =
3135 stack_entry->aux.avail_ssize -
3136 (new_stack_entry->end - new_stack_entry->start);
984263bc
MD
3137 if (is_procstack)
3138 vm->vm_ssize += btoc(new_stack_entry->end -
3139 new_stack_entry->start);
3140 }
3141 }
3142
3143done:
3144 if (use_read_lock)
3145 vm_map_unlock_read(map);
3146 else
3147 vm_map_unlock(map);
a108bf71 3148 vm_map_entry_release(count);
984263bc
MD
3149 return (rv);
3150}
3151
3152/*
3153 * Unshare the specified VM space for exec. If other processes are
3154 * mapped to it, then create a new one. The new vmspace is null.
3155 */
3156
3157void
29802dbb 3158vmspace_exec(struct proc *p, struct vmspace *vmcopy)
a108bf71 3159{
984263bc
MD
3160 struct vmspace *oldvmspace = p->p_vmspace;
3161 struct vmspace *newvmspace;
3162 vm_map_t map = &p->p_vmspace->vm_map;
3163
29802dbb
MD
3164 /*
3165 * If we are execing a resident vmspace we fork it, otherwise
239b4df9
MD
3166 * we create a new vmspace. Note that exitingcnt and upcalls
3167 * are not copied to the new vmspace.
29802dbb
MD
3168 */
3169 if (vmcopy) {
3170 newvmspace = vmspace_fork(vmcopy);
3171 } else {
3172 newvmspace = vmspace_alloc(map->min_offset, map->max_offset);
3173 bcopy(&oldvmspace->vm_startcopy, &newvmspace->vm_startcopy,
239b4df9
MD
3174 (caddr_t)&oldvmspace->vm_endcopy -
3175 (caddr_t)&oldvmspace->vm_startcopy);
29802dbb
MD
3176 }
3177
984263bc
MD
3178 /*
3179 * This code is written like this for prototype purposes. The
3180 * goal is to avoid running down the vmspace here, but let the
3181 * other process's that are still using the vmspace to finally
3182 * run it down. Even though there is little or no chance of blocking
3183 * here, it is a good idea to keep this form for future mods.
3184 */
984263bc
MD
3185 p->p_vmspace = newvmspace;
3186 pmap_pinit2(vmspace_pmap(newvmspace));
3187 if (p == curproc)
3188 pmap_activate(p);
29802dbb 3189 vmspace_free(oldvmspace);
984263bc
MD
3190}
3191
3192/*
3193 * Unshare the specified VM space for forcing COW. This
3194 * is called by rfork, for the (RFMEM|RFPROC) == 0 case.
239b4df9
MD
3195 *
3196 * The exitingcnt test is not strictly necessary but has been
3197 * included for code sanity (to make the code a bit more deterministic).
984263bc
MD
3198 */
3199
3200void
a108bf71
MD
3201vmspace_unshare(struct proc *p)
3202{
984263bc
MD
3203 struct vmspace *oldvmspace = p->p_vmspace;
3204 struct vmspace *newvmspace;
3205
239b4df9 3206 if (oldvmspace->vm_refcnt == 1 && oldvmspace->vm_exitingcnt == 0)
984263bc
MD
3207 return;
3208 newvmspace = vmspace_fork(oldvmspace);
984263bc
MD
3209 p->p_vmspace = newvmspace;
3210 pmap_pinit2(vmspace_pmap(newvmspace));
3211 if (p == curproc)
3212 pmap_activate(p);
29802dbb 3213 vmspace_free(oldvmspace);
984263bc 3214}
984263bc
MD
3215
3216/*
3217 * vm_map_lookup:
3218 *
3219 * Finds the VM object, offset, and
3220 * protection for a given virtual address in the
3221 * specified map, assuming a page fault of the
3222 * type specified.
3223 *
3224 * Leaves the map in question locked for read; return
3225 * values are guaranteed until a vm_map_lookup_done
3226 * call is performed. Note that the map argument
3227 * is in/out; the returned map must be used in
3228 * the call to vm_map_lookup_done.
3229 *
3230 * A handle (out_entry) is returned for use in
3231 * vm_map_lookup_done, to make that fast.
3232 *
3233 * If a lookup is requested with "write protection"
3234 * specified, the map may be changed to perform virtual
3235 * copying operations, although the data referenced will
3236 * remain the same.
3237 */
3238int
3239vm_map_lookup(vm_map_t *var_map, /* IN/OUT */
3240 vm_offset_t vaddr,
3241 vm_prot_t fault_typea,
3242 vm_map_entry_t *out_entry, /* OUT */
3243 vm_object_t *object, /* OUT */
3244 vm_pindex_t *pindex, /* OUT */
3245 vm_prot_t *out_prot, /* OUT */
3246 boolean_t *wired) /* OUT */
3247{
3248 vm_map_entry_t entry;
3249 vm_map_t map = *var_map;
3250 vm_prot_t prot;
3251 vm_prot_t fault_type = fault_typea;
3252 int use_read_lock = 1;
3253 int rv = KERN_SUCCESS;
3254
3255RetryLookup:
3256 if (use_read_lock)
3257 vm_map_lock_read(map);
3258 else
3259 vm_map_lock(map);
3260
3261 /*
3262 * If the map has an interesting hint, try it before calling full
3263 * blown lookup routine.
3264 */
3265 entry = map->hint;
3266 *out_entry = entry;
3267
3268 if ((entry == &map->header) ||
3269 (vaddr < entry->start) || (vaddr >= entry->end)) {
3270 vm_map_entry_t tmp_entry;
3271
3272 /*
3273 * Entry was either not a valid hint, or the vaddr was not
3274 * contained in the entry, so do a full lookup.
3275 */
3276 if (!vm_map_lookup_entry(map, vaddr, &tmp_entry)) {
3277 rv = KERN_INVALID_ADDRESS;
3278 goto done;
3279 }
3280
3281 entry = tmp_entry;
3282 *out_entry = entry;
3283 }
3284
3285 /*
3286 * Handle submaps.
3287 */
1b874851 3288 if (entry->maptype == VM_MAPTYPE_SUBMAP) {
984263bc
MD
3289 vm_map_t old_map = map;
3290
3291 *var_map = map = entry->object.sub_map;
3292 if (use_read_lock)
3293 vm_map_unlock_read(old_map);
3294 else
3295 vm_map_unlock(old_map);
3296 use_read_lock = 1;
3297 goto RetryLookup;
3298 }
3299
3300 /*
3301 * Check whether this task is allowed to have this page.
3302 * Note the special case for MAP_ENTRY_COW
3303 * pages with an override. This is to implement a forced
3304 * COW for debuggers.
3305 */
3306
3307 if (fault_type & VM_PROT_OVERRIDE_WRITE)
3308 prot = entry->max_protection;
3309 else
3310 prot = entry->protection;
3311
3312 fault_type &= (VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
3313 if ((fault_type & prot) != fault_type) {
3314 rv = KERN_PROTECTION_FAILURE;
3315 goto done;
3316 }
3317
3318 if ((entry->eflags & MAP_ENTRY_USER_WIRED) &&
3319 (entry->eflags & MAP_ENTRY_COW) &&
3320 (fault_type & VM_PROT_WRITE) &&
3321 (fault_typea & VM_PROT_OVERRIDE_WRITE) == 0) {
3322 rv = KERN_PROTECTION_FAILURE;
3323 goto done;
3324 }
3325
3326 /*
3327 * If this page is not pageable, we have to get it for all possible
3328 * accesses.
3329 */
984263bc
MD
3330 *wired = (entry->wired_count != 0);
3331 if (*wired)
3332 prot = fault_type = entry->protection;
3333
3334 /*
568e6804
MD
3335 * Virtual page tables may need to update the accessed (A) bit
3336 * in a page table entry. Upgrade the fault to a write fault for
3337 * that case if the map will support it. If the map does not support
3338 * it the page table entry simply will not be updated.
984263bc 3339 */
568e6804
MD
3340 if (entry->maptype == VM_MAPTYPE_VPAGETABLE) {
3341 if (prot & VM_PROT_WRITE)
3342 fault_type |= VM_PROT_WRITE;
3343 }
984263bc 3344
568e6804
MD
3345 /*
3346 * If the entry was copy-on-write, we either ...
3347 */
984263bc
MD
3348 if (entry->eflags & MAP_ENTRY_NEEDS_COPY) {
3349 /*
3350 * If we want to write the page, we may as well handle that
3351 * now since we've got the map locked.
3352 *
3353 * If we don't need to write the page, we just demote the
3354 * permissions allowed.
3355 */
3356
3357 if (fault_type & VM_PROT_WRITE) {
3358 /*
3359 * Make a new object, and place it in the object
3360 * chain. Note that no new references have appeared
3361 * -- one just moved from the map to the new
3362 * object.
3363 */
3364
3365 if (use_read_lock && vm_map_lock_upgrade(map)) {
3366 use_read_lock = 0;
3367 goto RetryLookup;
3368 }
3369 use_read_lock = 0;
3370
53025830 3371 vm_map_entry_shadow(entry);
984263bc
MD
3372 } else {
3373 /*
3374 * We're attempting to read a copy-on-write page --
3375 * don't allow writes.
3376 */
3377
3378 prot &= ~VM_PROT_WRITE;
3379 }
3380 }
3381
3382 /*
3383 * Create an object if necessary.
3384 */
3385 if (entry->object.vm_object == NULL &&
3386 !map->system_map) {
3387 if (use_read_lock && vm_map_lock_upgrade(map)) {
3388 use_read_lock = 0;
3389 goto RetryLookup;
3390 }
3391 use_read_lock = 0;
53025830 3392 vm_map_entry_allocate_object(entry);
984263bc
MD
3393 }
3394
3395 /*
3396 * Return the object/offset from this entry. If the entry was
3397 * copy-on-write or empty, it has been fixed up.
3398 */
3399
3400 *pindex = OFF_TO_IDX((vaddr - entry->start) + entry->offset);
3401 *object = entry->object.vm_object;
3402
3403 /*
3404 * Return whether this is the only map sharing this data. On
3405 * success we return with a read lock held on the map. On failure
3406 * we return with the map unlocked.
3407 */
3408 *out_prot = prot;
3409done:
3410 if (rv == KERN_SUCCESS) {
3411 if (use_read_lock == 0)
3412 vm_map_lock_downgrade(map);
3413 } else if (use_read_lock) {
3414 vm_map_unlock_read(map);
3415 } else {
3416 vm_map_unlock(map);
3417 }
3418 return (rv);
3419}
3420
3421/*
3422 * vm_map_lookup_done:
3423 *
3424 * Releases locks acquired by a vm_map_lookup
3425 * (according to the handle returned by that lookup).
3426 */
3427
3428void
a108bf71 3429vm_map_lookup_done(vm_map_t map, vm_map_entry_t entry, int count)
984263bc
MD
3430{
3431 /*
3432 * Unlock the main-level map
3433 */
984263bc 3434 vm_map_unlock_read(map);
a108bf71
MD
3435 if (count)
3436 vm_map_entry_release(count);
984263bc
MD
3437}
3438
984263bc
MD
3439#include "opt_ddb.h"
3440#ifdef DDB
3441#include <sys/kernel.h>
3442
3443#include <ddb/ddb.h>
3444
3445/*
3446 * vm_map_print: [ debug ]
3447 */
3448DB_SHOW_COMMAND(map, vm_map_print)
3449{
3450 static int nlines;
3451 /* XXX convert args. */
3452 vm_map_t map = (vm_map_t)addr;
3453 boolean_t full = have_addr;
3454
3455 vm_map_entry_t entry;
3456
3457 db_iprintf("Task map %p: pmap=%p, nentries=%d, version=%u\n",
3458 (void *)map,
3459 (void *)map->pmap, map->nentries, map->timestamp);
3460 nlines++;
3461
3462 if (!full && db_indent)
3463 return;
3464
3465 db_indent += 2;
3466 for (entry = map->header.next; entry != &map->header;
3467 entry = entry->next) {
3468 db_iprintf("map entry %p: start=%p, end=%p\n",
3469 (void *)entry, (void *)entry->start, (void *)entry->end);
3470 nlines++;
3471 {
3472 static char *inheritance_name[4] =
3473 {"share", "copy", "none", "donate_copy"};
3474
3475 db_iprintf(" prot=%x/%x/%s",
3476 entry->protection,
3477 entry->max_protection,
3478 inheritance_name[(int)(unsigned char)entry->inheritance]);
3479 if (entry->wired_count != 0)
3480 db_printf(", wired");
3481 }
1b874851 3482 if (entry->maptype == VM_MAPTYPE_SUBMAP) {
984263bc
MD
3483 /* XXX no %qd in kernel. Truncate entry->offset. */
3484 db_printf(", share=%p, offset=0x%lx\n",
3485 (void *)entry->object.sub_map,
3486 (long)entry->offset);
3487 nlines++;
3488 if ((entry->prev == &map->header) ||
3489 (entry->prev->object.sub_map !=
3490 entry->object.sub_map)) {
3491 db_indent += 2;
3492 vm_map_print((db_expr_t)(intptr_t)
3493 entry->object.sub_map,
3494 full, 0, (char *)0);
3495 db_indent -= 2;
3496 }
3497 } else {
3498 /* XXX no %qd in kernel. Truncate entry->offset. */
3499 db_printf(", object=%p, offset=0x%lx",
3500 (void *)entry->object.vm_object,
3501 (long)entry->offset);
3502 if (entry->eflags & MAP_ENTRY_COW)
3503 db_printf(", copy (%s)",
3504 (entry->eflags & MAP_ENTRY_NEEDS_COPY) ? "needed" : "done");
3505 db_printf("\n");
3506 nlines++;
3507
3508 if ((entry->prev == &map->header) ||
3509 (entry->prev->object.vm_object !=
3510 entry->object.vm_object)) {
3511 db_indent += 2;
3512 vm_object_print((db_expr_t)(intptr_t)
3513 entry->object.vm_object,
3514 full, 0, (char *)0);
3515 nlines += 4;
3516 db_indent -= 2;
3517 }
3518 }
3519 }
3520 db_indent -= 2;
3521 if (db_indent == 0)
3522 nlines = 0;
3523}
3524
3525
3526DB_SHOW_COMMAND(procvm, procvm)
3527{
3528 struct proc *p;
3529
3530 if (have_addr) {
3531 p = (struct proc *) addr;
3532 } else {
3533 p = curproc;
3534 }
3535
3536 db_printf("p = %p, vmspace = %p, map = %p, pmap = %p\n",
3537 (void *)p, (void *)p->p_vmspace, (void *)&p->p_vmspace->vm_map,
3538 (void *)vmspace_pmap(p->p_vmspace));
3539
3540 vm_map_print((db_expr_t)(intptr_t)&p->p_vmspace->vm_map, 1, 0, NULL);
3541}
3542
3543#endif /* DDB */