Subversion Repositories HelenOS

Rev

Rev 2985 | Rev 3129 | Go to most recent revision | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
703 jermar 1
/*
2071 jermar 2
 * Copyright (c) 2001-2006 Jakub Jermar
703 jermar 3
 * All rights reserved.
4
 *
5
 * Redistribution and use in source and binary forms, with or without
6
 * modification, are permitted provided that the following conditions
7
 * are met:
8
 *
9
 * - Redistributions of source code must retain the above copyright
10
 *   notice, this list of conditions and the following disclaimer.
11
 * - Redistributions in binary form must reproduce the above copyright
12
 *   notice, this list of conditions and the following disclaimer in the
13
 *   documentation and/or other materials provided with the distribution.
14
 * - The name of the author may not be used to endorse or promote products
15
 *   derived from this software without specific prior written permission.
16
 *
17
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
 */
28
 
1757 jermar 29
/** @addtogroup genericmm
1702 cejka 30
 * @{
31
 */
32
 
1248 jermar 33
/**
1702 cejka 34
 * @file
1248 jermar 35
 * @brief   Address space related functions.
36
 *
703 jermar 37
 * This file contains address space manipulation functions.
38
 * Roughly speaking, this is a higher-level client of
39
 * Virtual Address Translation (VAT) subsystem.
1248 jermar 40
 *
41
 * Functionality provided by this file allows one to
1757 jermar 42
 * create address spaces and create, resize and share
1248 jermar 43
 * address space areas.
44
 *
45
 * @see page.c
46
 *
703 jermar 47
 */
48
 
49
#include <mm/as.h>
756 jermar 50
#include <arch/mm/as.h>
703 jermar 51
#include <mm/page.h>
52
#include <mm/frame.h>
814 palkovsky 53
#include <mm/slab.h>
703 jermar 54
#include <mm/tlb.h>
55
#include <arch/mm/page.h>
56
#include <genarch/mm/page_pt.h>
1108 jermar 57
#include <genarch/mm/page_ht.h>
727 jermar 58
#include <mm/asid.h>
703 jermar 59
#include <arch/mm/asid.h>
2183 jermar 60
#include <preemption.h>
703 jermar 61
#include <synch/spinlock.h>
1380 jermar 62
#include <synch/mutex.h>
788 jermar 63
#include <adt/list.h>
1147 jermar 64
#include <adt/btree.h>
1235 jermar 65
#include <proc/task.h>
1288 jermar 66
#include <proc/thread.h>
1235 jermar 67
#include <arch/asm.h>
703 jermar 68
#include <panic.h>
69
#include <debug.h>
1235 jermar 70
#include <print.h>
703 jermar 71
#include <memstr.h>
1070 jermar 72
#include <macros.h>
703 jermar 73
#include <arch.h>
1235 jermar 74
#include <errno.h>
75
#include <config.h>
1387 jermar 76
#include <align.h>
1235 jermar 77
#include <arch/types.h>
1288 jermar 78
#include <syscall/copy.h>
79
#include <arch/interrupt.h>
703 jermar 80
 
2009 jermar 81
#ifdef CONFIG_VIRT_IDX_DCACHE
82
#include <arch/mm/cache.h>
83
#endif /* CONFIG_VIRT_IDX_DCACHE */
84
 
2125 decky 85
#ifndef __OBJC__
1757 jermar 86
/**
87
 * Each architecture decides what functions will be used to carry out
88
 * address space operations such as creating or locking page tables.
89
 */
756 jermar 90
as_operations_t *as_operations = NULL;
703 jermar 91
 
1890 jermar 92
/**
93
 * Slab for as_t objects.
94
 */
95
static slab_cache_t *as_slab;
2126 decky 96
#endif
1890 jermar 97
 
2087 jermar 98
/**
2170 jermar 99
 * This lock serializes access to the ASID subsystem.
100
 * It protects:
101
 * - inactive_as_with_asid_head list
102
 * - as->asid for each as of the as_t type
103
 * - asids_allocated counter
2087 jermar 104
 */
2170 jermar 105
SPINLOCK_INITIALIZE(asidlock);
823 jermar 106
 
107
/**
108
 * This list contains address spaces that are not active on any
109
 * processor and that have valid ASID.
110
 */
111
LIST_INITIALIZE(inactive_as_with_asid_head);
112
 
757 jermar 113
/** Kernel address space. */
114
as_t *AS_KERNEL = NULL;
115
 
1235 jermar 116
static int area_flags_to_page_flags(int aflags);
1780 jermar 117
static as_area_t *find_area_and_lock(as_t *as, uintptr_t va);
2087 jermar 118
static bool check_area_conflicts(as_t *as, uintptr_t va, size_t size,
119
    as_area_t *avoid_area);
1409 jermar 120
static void sh_info_remove_reference(share_info_t *sh_info);
703 jermar 121
 
2126 decky 122
#ifndef __OBJC__
1891 jermar 123
static int as_constructor(void *obj, int flags)
124
{
125
    as_t *as = (as_t *) obj;
126
    int rc;
127
 
128
    link_initialize(&as->inactive_as_with_asid_link);
129
    mutex_initialize(&as->lock);   
130
 
131
    rc = as_constructor_arch(as, flags);
132
 
133
    return rc;
134
}
135
 
136
static int as_destructor(void *obj)
137
{
138
    as_t *as = (as_t *) obj;
139
 
140
    return as_destructor_arch(as);
141
}
2126 decky 142
#endif
1891 jermar 143
 
756 jermar 144
/** Initialize address space subsystem. */
145
void as_init(void)
146
{
147
    as_arch_init();
2126 decky 148
 
149
#ifndef __OBJC__
1891 jermar 150
    as_slab = slab_cache_create("as_slab", sizeof(as_t), 0,
2087 jermar 151
        as_constructor, as_destructor, SLAB_CACHE_MAGDEFERRED);
2126 decky 152
#endif
1890 jermar 153
 
789 palkovsky 154
    AS_KERNEL = as_create(FLAG_AS_KERNEL);
1383 decky 155
    if (!AS_KERNEL)
156
        panic("can't create kernel address space\n");
157
 
756 jermar 158
}
159
 
757 jermar 160
/** Create address space.
161
 *
162
 * @param flags Flags that influence way in wich the address space is created.
163
 */
756 jermar 164
as_t *as_create(int flags)
703 jermar 165
{
166
    as_t *as;
167
 
2126 decky 168
#ifdef __OBJC__
169
    as = [as_t new];
170
    link_initialize(&as->inactive_as_with_asid_link);
171
    mutex_initialize(&as->lock);   
172
    (void) as_constructor_arch(as, flags);
173
#else
1890 jermar 174
    as = (as_t *) slab_alloc(as_slab, 0);
2126 decky 175
#endif
1891 jermar 176
    (void) as_create_arch(as, 0);
177
 
1147 jermar 178
    btree_create(&as->as_area_btree);
822 palkovsky 179
 
180
    if (flags & FLAG_AS_KERNEL)
181
        as->asid = ASID_KERNEL;
182
    else
183
        as->asid = ASID_INVALID;
184
 
2183 jermar 185
    atomic_set(&as->refcount, 0);
1415 jermar 186
    as->cpu_refcount = 0;
2089 decky 187
#ifdef AS_PAGE_TABLE
2106 jermar 188
    as->genarch.page_table = page_table_create(flags);
2089 decky 189
#else
190
    page_table_create(flags);
191
#endif
703 jermar 192
 
193
    return as;
194
}
195
 
1468 jermar 196
/** Destroy adress space.
197
 *
2087 jermar 198
 * When there are no tasks referencing this address space (i.e. its refcount is
199
 * zero), the address space can be destroyed.
2183 jermar 200
 *
201
 * We know that we don't hold any spinlock.
1468 jermar 202
 */
203
void as_destroy(as_t *as)
973 palkovsky 204
{
1468 jermar 205
    ipl_t ipl;
1594 jermar 206
    bool cond;
2183 jermar 207
    DEADLOCK_PROBE_INIT(p_asidlock);
973 palkovsky 208
 
2183 jermar 209
    ASSERT(atomic_get(&as->refcount) == 0);
1468 jermar 210
 
211
    /*
212
     * Since there is no reference to this area,
213
     * it is safe not to lock its mutex.
214
     */
2170 jermar 215
 
2183 jermar 216
    /*
217
     * We need to avoid deadlock between TLB shootdown and asidlock.
218
     * We therefore try to take asid conditionally and if we don't succeed,
219
     * we enable interrupts and try again. This is done while preemption is
220
     * disabled to prevent nested context switches. We also depend on the
221
     * fact that so far no spinlocks are held.
222
     */
223
    preemption_disable();
224
    ipl = interrupts_read();
225
retry:
226
    interrupts_disable();
227
    if (!spinlock_trylock(&asidlock)) {
228
        interrupts_enable();
229
        DEADLOCK_PROBE(p_asidlock, DEADLOCK_THRESHOLD);
230
        goto retry;
231
    }
232
    preemption_enable();    /* Interrupts disabled, enable preemption */
1587 jermar 233
    if (as->asid != ASID_INVALID && as != AS_KERNEL) {
1594 jermar 234
        if (as != AS && as->cpu_refcount == 0)
1587 jermar 235
            list_remove(&as->inactive_as_with_asid_link);
1468 jermar 236
        asid_put(as->asid);
237
    }
2170 jermar 238
    spinlock_unlock(&asidlock);
1468 jermar 239
 
240
    /*
241
     * Destroy address space areas of the address space.
1954 jermar 242
     * The B+tree must be walked carefully because it is
1594 jermar 243
     * also being destroyed.
1468 jermar 244
     */
1594 jermar 245
    for (cond = true; cond; ) {
1468 jermar 246
        btree_node_t *node;
1594 jermar 247
 
248
        ASSERT(!list_empty(&as->as_area_btree.leaf_head));
2087 jermar 249
        node = list_get_instance(as->as_area_btree.leaf_head.next,
250
            btree_node_t, leaf_link);
1594 jermar 251
 
252
        if ((cond = node->keys)) {
253
            as_area_destroy(as, node->key[0]);
254
        }
1468 jermar 255
    }
1495 jermar 256
 
1483 jermar 257
    btree_destroy(&as->as_area_btree);
2089 decky 258
#ifdef AS_PAGE_TABLE
2106 jermar 259
    page_table_destroy(as->genarch.page_table);
2089 decky 260
#else
261
    page_table_destroy(NULL);
262
#endif
1468 jermar 263
 
264
    interrupts_restore(ipl);
2126 decky 265
 
266
#ifdef __OBJC__
267
    [as free];
268
#else
1890 jermar 269
    slab_free(as_slab, as);
2126 decky 270
#endif
973 palkovsky 271
}
272
 
703 jermar 273
/** Create address space area of common attributes.
274
 *
275
 * The created address space area is added to the target address space.
276
 *
277
 * @param as Target address space.
1239 jermar 278
 * @param flags Flags of the area memory.
1048 jermar 279
 * @param size Size of area.
703 jermar 280
 * @param base Base address of area.
1239 jermar 281
 * @param attrs Attributes of the area.
1409 jermar 282
 * @param backend Address space area backend. NULL if no backend is used.
283
 * @param backend_data NULL or a pointer to an array holding two void *.
703 jermar 284
 *
285
 * @return Address space area on success or NULL on failure.
286
 */
2069 jermar 287
as_area_t *
288
as_area_create(as_t *as, int flags, size_t size, uintptr_t base, int attrs,
1424 jermar 289
           mem_backend_t *backend, mem_backend_data_t *backend_data)
703 jermar 290
{
291
    ipl_t ipl;
292
    as_area_t *a;
293
 
294
    if (base % PAGE_SIZE)
1048 jermar 295
        return NULL;
296
 
1233 jermar 297
    if (!size)
298
        return NULL;
299
 
1048 jermar 300
    /* Writeable executable areas are not supported. */
301
    if ((flags & AS_AREA_EXEC) && (flags & AS_AREA_WRITE))
302
        return NULL;
703 jermar 303
 
304
    ipl = interrupts_disable();
1380 jermar 305
    mutex_lock(&as->lock);
703 jermar 306
 
1048 jermar 307
    if (!check_area_conflicts(as, base, size, NULL)) {
1380 jermar 308
        mutex_unlock(&as->lock);
1048 jermar 309
        interrupts_restore(ipl);
310
        return NULL;
311
    }
703 jermar 312
 
822 palkovsky 313
    a = (as_area_t *) malloc(sizeof(as_area_t), 0);
703 jermar 314
 
1380 jermar 315
    mutex_initialize(&a->lock);
822 palkovsky 316
 
1424 jermar 317
    a->as = as;
1026 jermar 318
    a->flags = flags;
1239 jermar 319
    a->attributes = attrs;
1048 jermar 320
    a->pages = SIZE2FRAMES(size);
822 palkovsky 321
    a->base = base;
1409 jermar 322
    a->sh_info = NULL;
323
    a->backend = backend;
1424 jermar 324
    if (backend_data)
325
        a->backend_data = *backend_data;
326
    else
2087 jermar 327
        memsetb((uintptr_t) &a->backend_data, sizeof(a->backend_data),
328
            0);
1424 jermar 329
 
1387 jermar 330
    btree_create(&a->used_space);
822 palkovsky 331
 
1147 jermar 332
    btree_insert(&as->as_area_btree, base, (void *) a, NULL);
822 palkovsky 333
 
1380 jermar 334
    mutex_unlock(&as->lock);
703 jermar 335
    interrupts_restore(ipl);
704 jermar 336
 
703 jermar 337
    return a;
338
}
339
 
1235 jermar 340
/** Find address space area and change it.
341
 *
342
 * @param as Address space.
2087 jermar 343
 * @param address Virtual address belonging to the area to be changed. Must be
344
 *     page-aligned.
1235 jermar 345
 * @param size New size of the virtual memory block starting at address.
346
 * @param flags Flags influencing the remap operation. Currently unused.
347
 *
1306 jermar 348
 * @return Zero on success or a value from @ref errno.h otherwise.
1235 jermar 349
 */
1780 jermar 350
int as_area_resize(as_t *as, uintptr_t address, size_t size, int flags)
1235 jermar 351
{
1306 jermar 352
    as_area_t *area;
1235 jermar 353
    ipl_t ipl;
354
    size_t pages;
355
 
356
    ipl = interrupts_disable();
1380 jermar 357
    mutex_lock(&as->lock);
1235 jermar 358
 
359
    /*
360
     * Locate the area.
361
     */
362
    area = find_area_and_lock(as, address);
363
    if (!area) {
1380 jermar 364
        mutex_unlock(&as->lock);
1235 jermar 365
        interrupts_restore(ipl);
1306 jermar 366
        return ENOENT;
1235 jermar 367
    }
368
 
1424 jermar 369
    if (area->backend == &phys_backend) {
1235 jermar 370
        /*
371
         * Remapping of address space areas associated
372
         * with memory mapped devices is not supported.
373
         */
1380 jermar 374
        mutex_unlock(&area->lock);
375
        mutex_unlock(&as->lock);
1235 jermar 376
        interrupts_restore(ipl);
1306 jermar 377
        return ENOTSUP;
1235 jermar 378
    }
1409 jermar 379
    if (area->sh_info) {
380
        /*
381
         * Remapping of shared address space areas
382
         * is not supported.
383
         */
384
        mutex_unlock(&area->lock);
385
        mutex_unlock(&as->lock);
386
        interrupts_restore(ipl);
387
        return ENOTSUP;
388
    }
1235 jermar 389
 
390
    pages = SIZE2FRAMES((address - area->base) + size);
391
    if (!pages) {
392
        /*
393
         * Zero size address space areas are not allowed.
394
         */
1380 jermar 395
        mutex_unlock(&area->lock);
396
        mutex_unlock(&as->lock);
1235 jermar 397
        interrupts_restore(ipl);
1306 jermar 398
        return EPERM;
1235 jermar 399
    }
400
 
401
    if (pages < area->pages) {
1403 jermar 402
        bool cond;
1780 jermar 403
        uintptr_t start_free = area->base + pages*PAGE_SIZE;
1235 jermar 404
 
405
        /*
406
         * Shrinking the area.
407
         * No need to check for overlaps.
408
         */
1403 jermar 409
 
410
        /*
1436 jermar 411
         * Start TLB shootdown sequence.
412
         */
2087 jermar 413
        tlb_shootdown_start(TLB_INVL_PAGES, AS->asid, area->base +
414
            pages * PAGE_SIZE, area->pages - pages);
1436 jermar 415
 
416
        /*
1403 jermar 417
         * Remove frames belonging to used space starting from
418
         * the highest addresses downwards until an overlap with
419
         * the resized address space area is found. Note that this
420
         * is also the right way to remove part of the used_space
421
         * B+tree leaf list.
422
         */    
423
        for (cond = true; cond;) {
424
            btree_node_t *node;
425
 
426
            ASSERT(!list_empty(&area->used_space.leaf_head));
2087 jermar 427
            node =
428
                list_get_instance(area->used_space.leaf_head.prev,
429
                btree_node_t, leaf_link);
1403 jermar 430
            if ((cond = (bool) node->keys)) {
1780 jermar 431
                uintptr_t b = node->key[node->keys - 1];
2087 jermar 432
                count_t c =
433
                    (count_t) node->value[node->keys - 1];
2745 decky 434
                unsigned int i = 0;
1235 jermar 435
 
2087 jermar 436
                if (overlaps(b, c * PAGE_SIZE, area->base,
2133 jermar 437
                    pages * PAGE_SIZE)) {
1403 jermar 438
 
2087 jermar 439
                    if (b + c * PAGE_SIZE <= start_free) {
1403 jermar 440
                        /*
2087 jermar 441
                         * The whole interval fits
442
                         * completely in the resized
443
                         * address space area.
1403 jermar 444
                         */
445
                        break;
446
                    }
447
 
448
                    /*
2087 jermar 449
                     * Part of the interval corresponding
450
                     * to b and c overlaps with the resized
451
                     * address space area.
1403 jermar 452
                     */
453
 
454
                    cond = false;   /* we are almost done */
455
                    i = (start_free - b) >> PAGE_WIDTH;
2087 jermar 456
                    if (!used_space_remove(area, start_free,
457
                        c - i))
458
                        panic("Could not remove used "
459
                            "space.\n");
1403 jermar 460
                } else {
461
                    /*
2087 jermar 462
                     * The interval of used space can be
463
                     * completely removed.
1403 jermar 464
                     */
465
                    if (!used_space_remove(area, b, c))
2087 jermar 466
                        panic("Could not remove used "
467
                            "space.\n");
1403 jermar 468
                }
469
 
470
                for (; i < c; i++) {
471
                    pte_t *pte;
472
 
473
                    page_table_lock(as, false);
2087 jermar 474
                    pte = page_mapping_find(as, b +
475
                        i * PAGE_SIZE);
476
                    ASSERT(pte && PTE_VALID(pte) &&
477
                        PTE_PRESENT(pte));
478
                    if (area->backend &&
479
                        area->backend->frame_free) {
1424 jermar 480
                        area->backend->frame_free(area,
2087 jermar 481
                            b + i * PAGE_SIZE,
482
                            PTE_GET_FRAME(pte));
1409 jermar 483
                    }
2087 jermar 484
                    page_mapping_remove(as, b +
485
                        i * PAGE_SIZE);
1403 jermar 486
                    page_table_unlock(as, false);
487
                }
1235 jermar 488
            }
489
        }
1436 jermar 490
 
1235 jermar 491
        /*
1436 jermar 492
         * Finish TLB shootdown sequence.
1235 jermar 493
         */
2183 jermar 494
 
2087 jermar 495
        tlb_invalidate_pages(as->asid, area->base + pages * PAGE_SIZE,
496
            area->pages - pages);
1889 jermar 497
        /*
498
         * Invalidate software translation caches (e.g. TSB on sparc64).
499
         */
2087 jermar 500
        as_invalidate_translation_cache(as, area->base +
501
            pages * PAGE_SIZE, area->pages - pages);
2183 jermar 502
        tlb_shootdown_finalize();
503
 
1235 jermar 504
    } else {
505
        /*
506
         * Growing the area.
507
         * Check for overlaps with other address space areas.
508
         */
2087 jermar 509
        if (!check_area_conflicts(as, address, pages * PAGE_SIZE,
510
            area)) {
1380 jermar 511
            mutex_unlock(&area->lock);
512
            mutex_unlock(&as->lock);       
1235 jermar 513
            interrupts_restore(ipl);
1306 jermar 514
            return EADDRNOTAVAIL;
1235 jermar 515
        }
516
    }
517
 
518
    area->pages = pages;
519
 
1380 jermar 520
    mutex_unlock(&area->lock);
521
    mutex_unlock(&as->lock);
1235 jermar 522
    interrupts_restore(ipl);
523
 
1306 jermar 524
    return 0;
1235 jermar 525
}
526
 
1306 jermar 527
/** Destroy address space area.
528
 *
529
 * @param as Address space.
530
 * @param address Address withing the area to be deleted.
531
 *
532
 * @return Zero on success or a value from @ref errno.h on failure.
533
 */
1780 jermar 534
int as_area_destroy(as_t *as, uintptr_t address)
1306 jermar 535
{
536
    as_area_t *area;
1780 jermar 537
    uintptr_t base;
1495 jermar 538
    link_t *cur;
1306 jermar 539
    ipl_t ipl;
540
 
541
    ipl = interrupts_disable();
1380 jermar 542
    mutex_lock(&as->lock);
1306 jermar 543
 
544
    area = find_area_and_lock(as, address);
545
    if (!area) {
1380 jermar 546
        mutex_unlock(&as->lock);
1306 jermar 547
        interrupts_restore(ipl);
548
        return ENOENT;
549
    }
550
 
1403 jermar 551
    base = area->base;
552
 
1411 jermar 553
    /*
1436 jermar 554
     * Start TLB shootdown sequence.
555
     */
1889 jermar 556
    tlb_shootdown_start(TLB_INVL_PAGES, as->asid, area->base, area->pages);
1436 jermar 557
 
558
    /*
1411 jermar 559
     * Visit only the pages mapped by used_space B+tree.
560
     */
2087 jermar 561
    for (cur = area->used_space.leaf_head.next;
562
        cur != &area->used_space.leaf_head; cur = cur->next) {
1411 jermar 563
        btree_node_t *node;
2745 decky 564
        unsigned int i;
1403 jermar 565
 
1495 jermar 566
        node = list_get_instance(cur, btree_node_t, leaf_link);
567
        for (i = 0; i < node->keys; i++) {
1780 jermar 568
            uintptr_t b = node->key[i];
1495 jermar 569
            count_t j;
1411 jermar 570
            pte_t *pte;
1403 jermar 571
 
1495 jermar 572
            for (j = 0; j < (count_t) node->value[i]; j++) {
1411 jermar 573
                page_table_lock(as, false);
2087 jermar 574
                pte = page_mapping_find(as, b + j * PAGE_SIZE);
575
                ASSERT(pte && PTE_VALID(pte) &&
576
                    PTE_PRESENT(pte));
577
                if (area->backend &&
578
                    area->backend->frame_free) {
579
                    area->backend->frame_free(area, b +
2133 jermar 580
                        j * PAGE_SIZE, PTE_GET_FRAME(pte));
1403 jermar 581
                }
2087 jermar 582
                page_mapping_remove(as, b + j * PAGE_SIZE);            
1411 jermar 583
                page_table_unlock(as, false);
1306 jermar 584
            }
585
        }
586
    }
1403 jermar 587
 
1306 jermar 588
    /*
1436 jermar 589
     * Finish TLB shootdown sequence.
1306 jermar 590
     */
2183 jermar 591
 
1889 jermar 592
    tlb_invalidate_pages(as->asid, area->base, area->pages);
593
    /*
2087 jermar 594
     * Invalidate potential software translation caches (e.g. TSB on
595
     * sparc64).
1889 jermar 596
     */
597
    as_invalidate_translation_cache(as, area->base, area->pages);
2183 jermar 598
    tlb_shootdown_finalize();
1889 jermar 599
 
1436 jermar 600
    btree_destroy(&area->used_space);
1306 jermar 601
 
1309 jermar 602
    area->attributes |= AS_AREA_ATTR_PARTIAL;
1409 jermar 603
 
604
    if (area->sh_info)
605
        sh_info_remove_reference(area->sh_info);
606
 
1380 jermar 607
    mutex_unlock(&area->lock);
1306 jermar 608
 
609
    /*
610
     * Remove the empty area from address space.
611
     */
1889 jermar 612
    btree_remove(&as->as_area_btree, base, NULL);
1306 jermar 613
 
1309 jermar 614
    free(area);
615
 
1889 jermar 616
    mutex_unlock(&as->lock);
1306 jermar 617
    interrupts_restore(ipl);
618
    return 0;
619
}
620
 
1413 jermar 621
/** Share address space area with another or the same address space.
1235 jermar 622
 *
1424 jermar 623
 * Address space area mapping is shared with a new address space area.
624
 * If the source address space area has not been shared so far,
625
 * a new sh_info is created. The new address space area simply gets the
626
 * sh_info of the source area. The process of duplicating the
627
 * mapping is done through the backend share function.
1413 jermar 628
 *
1417 jermar 629
 * @param src_as Pointer to source address space.
1239 jermar 630
 * @param src_base Base address of the source address space area.
1417 jermar 631
 * @param acc_size Expected size of the source area.
1428 palkovsky 632
 * @param dst_as Pointer to destination address space.
1417 jermar 633
 * @param dst_base Target base address.
634
 * @param dst_flags_mask Destination address space area flags mask.
1235 jermar 635
 *
2007 jermar 636
 * @return Zero on success or ENOENT if there is no such task or if there is no
637
 * such address space area, EPERM if there was a problem in accepting the area
638
 * or ENOMEM if there was a problem in allocating destination address space
639
 * area. ENOTSUP is returned if the address space area backend does not support
2141 jermar 640
 * sharing.
1235 jermar 641
 */
1780 jermar 642
int as_area_share(as_t *src_as, uintptr_t src_base, size_t acc_size,
2647 jermar 643
    as_t *dst_as, uintptr_t dst_base, int dst_flags_mask)
1235 jermar 644
{
645
    ipl_t ipl;
1239 jermar 646
    int src_flags;
647
    size_t src_size;
648
    as_area_t *src_area, *dst_area;
1413 jermar 649
    share_info_t *sh_info;
1424 jermar 650
    mem_backend_t *src_backend;
651
    mem_backend_data_t src_backend_data;
1434 palkovsky 652
 
1235 jermar 653
    ipl = interrupts_disable();
1380 jermar 654
    mutex_lock(&src_as->lock);
1329 palkovsky 655
    src_area = find_area_and_lock(src_as, src_base);
1239 jermar 656
    if (!src_area) {
1238 jermar 657
        /*
658
         * Could not find the source address space area.
659
         */
1380 jermar 660
        mutex_unlock(&src_as->lock);
1238 jermar 661
        interrupts_restore(ipl);
662
        return ENOENT;
663
    }
2007 jermar 664
 
1424 jermar 665
    if (!src_area->backend || !src_area->backend->share) {
1413 jermar 666
        /*
1851 jermar 667
         * There is no backend or the backend does not
1424 jermar 668
         * know how to share the area.
1413 jermar 669
         */
670
        mutex_unlock(&src_area->lock);
671
        mutex_unlock(&src_as->lock);
672
        interrupts_restore(ipl);
673
        return ENOTSUP;
674
    }
675
 
1239 jermar 676
    src_size = src_area->pages * PAGE_SIZE;
677
    src_flags = src_area->flags;
1424 jermar 678
    src_backend = src_area->backend;
679
    src_backend_data = src_area->backend_data;
1544 palkovsky 680
 
681
    /* Share the cacheable flag from the original mapping */
682
    if (src_flags & AS_AREA_CACHEABLE)
683
        dst_flags_mask |= AS_AREA_CACHEABLE;
684
 
2087 jermar 685
    if (src_size != acc_size ||
686
        (src_flags & dst_flags_mask) != dst_flags_mask) {
1413 jermar 687
        mutex_unlock(&src_area->lock);
688
        mutex_unlock(&src_as->lock);
1235 jermar 689
        interrupts_restore(ipl);
690
        return EPERM;
691
    }
1413 jermar 692
 
1235 jermar 693
    /*
1413 jermar 694
     * Now we are committed to sharing the area.
1954 jermar 695
     * First, prepare the area for sharing.
1413 jermar 696
     * Then it will be safe to unlock it.
697
     */
698
    sh_info = src_area->sh_info;
699
    if (!sh_info) {
700
        sh_info = (share_info_t *) malloc(sizeof(share_info_t), 0);
701
        mutex_initialize(&sh_info->lock);
702
        sh_info->refcount = 2;
703
        btree_create(&sh_info->pagemap);
704
        src_area->sh_info = sh_info;
2647 jermar 705
        /*
706
         * Call the backend to setup sharing.
707
         */
708
        src_area->backend->share(src_area);
1413 jermar 709
    } else {
710
        mutex_lock(&sh_info->lock);
711
        sh_info->refcount++;
712
        mutex_unlock(&sh_info->lock);
713
    }
714
 
715
    mutex_unlock(&src_area->lock);
716
    mutex_unlock(&src_as->lock);
717
 
718
    /*
1239 jermar 719
     * Create copy of the source address space area.
720
     * The destination area is created with AS_AREA_ATTR_PARTIAL
721
     * attribute set which prevents race condition with
722
     * preliminary as_page_fault() calls.
1417 jermar 723
     * The flags of the source area are masked against dst_flags_mask
724
     * to support sharing in less privileged mode.
1235 jermar 725
     */
1461 palkovsky 726
    dst_area = as_area_create(dst_as, dst_flags_mask, src_size, dst_base,
2087 jermar 727
        AS_AREA_ATTR_PARTIAL, src_backend, &src_backend_data);
1239 jermar 728
    if (!dst_area) {
1235 jermar 729
        /*
730
         * Destination address space area could not be created.
731
         */
1413 jermar 732
        sh_info_remove_reference(sh_info);
733
 
1235 jermar 734
        interrupts_restore(ipl);
735
        return ENOMEM;
736
    }
2009 jermar 737
 
1235 jermar 738
    /*
1239 jermar 739
     * Now the destination address space area has been
740
     * fully initialized. Clear the AS_AREA_ATTR_PARTIAL
1413 jermar 741
     * attribute and set the sh_info.
1239 jermar 742
     */
2009 jermar 743
    mutex_lock(&dst_as->lock); 
1380 jermar 744
    mutex_lock(&dst_area->lock);
1239 jermar 745
    dst_area->attributes &= ~AS_AREA_ATTR_PARTIAL;
1413 jermar 746
    dst_area->sh_info = sh_info;
1380 jermar 747
    mutex_unlock(&dst_area->lock);
2009 jermar 748
    mutex_unlock(&dst_as->lock);   
749
 
1235 jermar 750
    interrupts_restore(ipl);
751
 
752
    return 0;
753
}
754
 
1423 jermar 755
/** Check access mode for address space area.
756
 *
757
 * The address space area must be locked prior to this call.
758
 *
759
 * @param area Address space area.
760
 * @param access Access mode.
761
 *
762
 * @return False if access violates area's permissions, true otherwise.
763
 */
764
bool as_area_check_access(as_area_t *area, pf_access_t access)
765
{
766
    int flagmap[] = {
767
        [PF_ACCESS_READ] = AS_AREA_READ,
768
        [PF_ACCESS_WRITE] = AS_AREA_WRITE,
769
        [PF_ACCESS_EXEC] = AS_AREA_EXEC
770
    };
771
 
772
    if (!(area->flags & flagmap[access]))
773
        return false;
774
 
775
    return true;
776
}
777
 
2984 svoboda 778
/** Change adress area flags.
779
 *
780
 * The idea is to have the same data, but with a different access mode.
781
 * This is needed e.g. for writing code into memory and then executing it.
782
 * In order for this to work properly, this may copy the data
783
 * into private anonymous memory (unless it's already there).
784
 *
785
 * @param as Address space.
786
 * @param flags Flags of the area memory.
787
 * @param address Address withing the area to be changed.
788
 *
789
 * @return Zero on success or a value from @ref errno.h on failure.
790
 */
791
int as_area_change_flags(as_t *as, int flags, uintptr_t address)
792
{
793
    as_area_t *area;
794
    uintptr_t base;
795
    link_t *cur;
796
    ipl_t ipl;
2985 svoboda 797
    int page_flags;
2986 svoboda 798
    uintptr_t old_frame;
2984 svoboda 799
 
2985 svoboda 800
    /* Flags for the new memory mapping */
801
    page_flags = area_flags_to_page_flags(flags);
802
 
2984 svoboda 803
    ipl = interrupts_disable();
804
    mutex_lock(&as->lock);
805
 
806
    area = find_area_and_lock(as, address);
807
    if (!area) {
808
        mutex_unlock(&as->lock);
809
        interrupts_restore(ipl);
810
        return ENOENT;
811
    }
812
 
813
    if (area->sh_info || area->backend != &anon_backend) {
814
        /* Copying shared areas not supported yet */
815
        /* Copying non-anonymous memory not supported yet */
2985 svoboda 816
        mutex_unlock(&area->lock);
2984 svoboda 817
        mutex_unlock(&as->lock);
818
        interrupts_restore(ipl);
819
        return ENOTSUP;
820
    }
821
 
822
    base = area->base;
823
 
824
    /*
825
     * Start TLB shootdown sequence.
826
     */
827
    tlb_shootdown_start(TLB_INVL_PAGES, as->asid, area->base, area->pages);
828
 
829
    /*
830
     * Visit only the pages mapped by used_space B+tree.
831
     */
832
    for (cur = area->used_space.leaf_head.next;
833
        cur != &area->used_space.leaf_head; cur = cur->next) {
834
        btree_node_t *node;
835
        unsigned int i;
836
 
837
        node = list_get_instance(cur, btree_node_t, leaf_link);
838
        for (i = 0; i < node->keys; i++) {
839
            uintptr_t b = node->key[i];
840
            count_t j;
841
            pte_t *pte;
842
 
843
            for (j = 0; j < (count_t) node->value[i]; j++) {
844
                page_table_lock(as, false);
845
                pte = page_mapping_find(as, b + j * PAGE_SIZE);
846
                ASSERT(pte && PTE_VALID(pte) &&
847
                    PTE_PRESENT(pte));
2985 svoboda 848
                old_frame = PTE_GET_FRAME_ARCH(pte);
2984 svoboda 849
 
850
                /* Remove old mapping and insert the new one */
851
                page_mapping_remove(as, b + j * PAGE_SIZE);
852
                page_mapping_insert(as, b + j * PAGE_SIZE,
2985 svoboda 853
                    old_frame, page_flags);
854
 
2984 svoboda 855
                page_table_unlock(as, false);
856
            }
857
        }
858
    }
859
 
860
    /*
861
     * Finish TLB shootdown sequence.
862
     */
863
 
864
    tlb_invalidate_pages(as->asid, area->base, area->pages);
865
    /*
866
     * Invalidate potential software translation caches (e.g. TSB on
867
     * sparc64).
868
     */
869
    as_invalidate_translation_cache(as, area->base, area->pages);
870
    tlb_shootdown_finalize();
871
 
872
    mutex_unlock(&area->lock);
873
    mutex_unlock(&as->lock);
874
    interrupts_restore(ipl);
875
 
876
    return 0;
877
}
878
 
879
 
703 jermar 880
/** Handle page fault within the current address space.
881
 *
1409 jermar 882
 * This is the high-level page fault handler. It decides
883
 * whether the page fault can be resolved by any backend
884
 * and if so, it invokes the backend to resolve the page
885
 * fault.
886
 *
703 jermar 887
 * Interrupts are assumed disabled.
888
 *
889
 * @param page Faulting page.
1411 jermar 890
 * @param access Access mode that caused the fault (i.e. read/write/exec).
1288 jermar 891
 * @param istate Pointer to interrupted state.
703 jermar 892
 *
1409 jermar 893
 * @return AS_PF_FAULT on page fault, AS_PF_OK on success or AS_PF_DEFER if the
894
 *     fault was caused by copy_to_uspace() or copy_from_uspace().
703 jermar 895
 */
1780 jermar 896
int as_page_fault(uintptr_t page, pf_access_t access, istate_t *istate)
703 jermar 897
{
1044 jermar 898
    pte_t *pte;
977 jermar 899
    as_area_t *area;
703 jermar 900
 
1380 jermar 901
    if (!THREAD)
1409 jermar 902
        return AS_PF_FAULT;
1380 jermar 903
 
703 jermar 904
    ASSERT(AS);
1044 jermar 905
 
1380 jermar 906
    mutex_lock(&AS->lock);
977 jermar 907
    area = find_area_and_lock(AS, page);   
703 jermar 908
    if (!area) {
909
        /*
910
         * No area contained mapping for 'page'.
911
         * Signal page fault to low-level handler.
912
         */
1380 jermar 913
        mutex_unlock(&AS->lock);
1288 jermar 914
        goto page_fault;
703 jermar 915
    }
916
 
1239 jermar 917
    if (area->attributes & AS_AREA_ATTR_PARTIAL) {
918
        /*
919
         * The address space area is not fully initialized.
920
         * Avoid possible race by returning error.
921
         */
1380 jermar 922
        mutex_unlock(&area->lock);
923
        mutex_unlock(&AS->lock);
1288 jermar 924
        goto page_fault;       
1239 jermar 925
    }
926
 
1424 jermar 927
    if (!area->backend || !area->backend->page_fault) {
1409 jermar 928
        /*
929
         * The address space area is not backed by any backend
930
         * or the backend cannot handle page faults.
931
         */
932
        mutex_unlock(&area->lock);
933
        mutex_unlock(&AS->lock);
934
        goto page_fault;       
935
    }
1179 jermar 936
 
1044 jermar 937
    page_table_lock(AS, false);
938
 
703 jermar 939
    /*
1044 jermar 940
     * To avoid race condition between two page faults
941
     * on the same address, we need to make sure
942
     * the mapping has not been already inserted.
943
     */
944
    if ((pte = page_mapping_find(AS, page))) {
945
        if (PTE_PRESENT(pte)) {
1423 jermar 946
            if (((access == PF_ACCESS_READ) && PTE_READABLE(pte)) ||
2087 jermar 947
                (access == PF_ACCESS_WRITE && PTE_WRITABLE(pte)) ||
948
                (access == PF_ACCESS_EXEC && PTE_EXECUTABLE(pte))) {
1423 jermar 949
                page_table_unlock(AS, false);
950
                mutex_unlock(&area->lock);
951
                mutex_unlock(&AS->lock);
952
                return AS_PF_OK;
953
            }
1044 jermar 954
        }
955
    }
1409 jermar 956
 
1044 jermar 957
    /*
1409 jermar 958
     * Resort to the backend page fault handler.
703 jermar 959
     */
1424 jermar 960
    if (area->backend->page_fault(area, page, access) != AS_PF_OK) {
1409 jermar 961
        page_table_unlock(AS, false);
962
        mutex_unlock(&area->lock);
963
        mutex_unlock(&AS->lock);
964
        goto page_fault;
965
    }
703 jermar 966
 
1044 jermar 967
    page_table_unlock(AS, false);
1380 jermar 968
    mutex_unlock(&area->lock);
969
    mutex_unlock(&AS->lock);
1288 jermar 970
    return AS_PF_OK;
971
 
972
page_fault:
973
    if (THREAD->in_copy_from_uspace) {
974
        THREAD->in_copy_from_uspace = false;
2087 jermar 975
        istate_set_retaddr(istate,
976
            (uintptr_t) &memcpy_from_uspace_failover_address);
1288 jermar 977
    } else if (THREAD->in_copy_to_uspace) {
978
        THREAD->in_copy_to_uspace = false;
2087 jermar 979
        istate_set_retaddr(istate,
980
            (uintptr_t) &memcpy_to_uspace_failover_address);
1288 jermar 981
    } else {
982
        return AS_PF_FAULT;
983
    }
984
 
985
    return AS_PF_DEFER;
703 jermar 986
}
987
 
823 jermar 988
/** Switch address spaces.
703 jermar 989
 *
1380 jermar 990
 * Note that this function cannot sleep as it is essentially a part of
2170 jermar 991
 * scheduling. Sleeping here would lead to deadlock on wakeup. Another
992
 * thing which is forbidden in this context is locking the address space.
1380 jermar 993
 *
2183 jermar 994
 * When this function is enetered, no spinlocks may be held.
995
 *
823 jermar 996
 * @param old Old address space or NULL.
997
 * @param new New address space.
703 jermar 998
 */
2106 jermar 999
void as_switch(as_t *old_as, as_t *new_as)
703 jermar 1000
{
2183 jermar 1001
    DEADLOCK_PROBE_INIT(p_asidlock);
1002
    preemption_disable();
1003
retry:
1004
    (void) interrupts_disable();
1005
    if (!spinlock_trylock(&asidlock)) {
1006
        /*
1007
         * Avoid deadlock with TLB shootdown.
1008
         * We can enable interrupts here because
1009
         * preemption is disabled. We should not be
1010
         * holding any other lock.
1011
         */
1012
        (void) interrupts_enable();
1013
        DEADLOCK_PROBE(p_asidlock, DEADLOCK_THRESHOLD);
1014
        goto retry;
1015
    }
1016
    preemption_enable();
703 jermar 1017
 
1018
    /*
823 jermar 1019
     * First, take care of the old address space.
1020
     */
2106 jermar 1021
    if (old_as) {
1022
        ASSERT(old_as->cpu_refcount);
1023
        if((--old_as->cpu_refcount == 0) && (old_as != AS_KERNEL)) {
823 jermar 1024
            /*
1025
             * The old address space is no longer active on
1026
             * any processor. It can be appended to the
1027
             * list of inactive address spaces with assigned
1028
             * ASID.
1029
             */
2141 jermar 1030
            ASSERT(old_as->asid != ASID_INVALID);
1031
            list_append(&old_as->inactive_as_with_asid_link,
1032
                &inactive_as_with_asid_head);
823 jermar 1033
        }
1890 jermar 1034
 
1035
        /*
1036
         * Perform architecture-specific tasks when the address space
1037
         * is being removed from the CPU.
1038
         */
2106 jermar 1039
        as_deinstall_arch(old_as);
823 jermar 1040
    }
1041
 
1042
    /*
1043
     * Second, prepare the new address space.
1044
     */
2106 jermar 1045
    if ((new_as->cpu_refcount++ == 0) && (new_as != AS_KERNEL)) {
2170 jermar 1046
        if (new_as->asid != ASID_INVALID)
2106 jermar 1047
            list_remove(&new_as->inactive_as_with_asid_link);
2170 jermar 1048
        else
1049
            new_as->asid = asid_get();
823 jermar 1050
    }
2106 jermar 1051
#ifdef AS_PAGE_TABLE
1052
    SET_PTL0_ADDRESS(new_as->genarch.page_table);
1053
#endif
823 jermar 1054
 
1055
    /*
703 jermar 1056
     * Perform architecture-specific steps.
727 jermar 1057
     * (e.g. write ASID to hardware register etc.)
703 jermar 1058
     */
2106 jermar 1059
    as_install_arch(new_as);
2170 jermar 1060
 
1061
    spinlock_unlock(&asidlock);
703 jermar 1062
 
2106 jermar 1063
    AS = new_as;
703 jermar 1064
}
754 jermar 1065
 
1235 jermar 1066
/** Convert address space area flags to page flags.
754 jermar 1067
 *
1235 jermar 1068
 * @param aflags Flags of some address space area.
754 jermar 1069
 *
1235 jermar 1070
 * @return Flags to be passed to page_mapping_insert().
754 jermar 1071
 */
1235 jermar 1072
int area_flags_to_page_flags(int aflags)
754 jermar 1073
{
1074
    int flags;
1075
 
1178 jermar 1076
    flags = PAGE_USER | PAGE_PRESENT;
754 jermar 1077
 
1235 jermar 1078
    if (aflags & AS_AREA_READ)
1026 jermar 1079
        flags |= PAGE_READ;
1080
 
1235 jermar 1081
    if (aflags & AS_AREA_WRITE)
1026 jermar 1082
        flags |= PAGE_WRITE;
1083
 
1235 jermar 1084
    if (aflags & AS_AREA_EXEC)
1026 jermar 1085
        flags |= PAGE_EXEC;
1086
 
1424 jermar 1087
    if (aflags & AS_AREA_CACHEABLE)
1178 jermar 1088
        flags |= PAGE_CACHEABLE;
1089
 
754 jermar 1090
    return flags;
1091
}
756 jermar 1092
 
1235 jermar 1093
/** Compute flags for virtual address translation subsytem.
1094
 *
1095
 * The address space area must be locked.
1096
 * Interrupts must be disabled.
1097
 *
1098
 * @param a Address space area.
1099
 *
1100
 * @return Flags to be used in page_mapping_insert().
1101
 */
1409 jermar 1102
int as_area_get_flags(as_area_t *a)
1235 jermar 1103
{
1104
    return area_flags_to_page_flags(a->flags);
1105
}
1106
 
756 jermar 1107
/** Create page table.
1108
 *
1109
 * Depending on architecture, create either address space
1110
 * private or global page table.
1111
 *
1112
 * @param flags Flags saying whether the page table is for kernel address space.
1113
 *
1114
 * @return First entry of the page table.
1115
 */
1116
pte_t *page_table_create(int flags)
1117
{
2125 decky 1118
#ifdef __OBJC__
1119
    return [as_t page_table_create: flags];
1120
#else
1121
    ASSERT(as_operations);
1122
    ASSERT(as_operations->page_table_create);
1123
 
1124
    return as_operations->page_table_create(flags);
1125
#endif
756 jermar 1126
}
977 jermar 1127
 
1468 jermar 1128
/** Destroy page table.
1129
 *
1130
 * Destroy page table in architecture specific way.
1131
 *
1132
 * @param page_table Physical address of PTL0.
1133
 */
1134
void page_table_destroy(pte_t *page_table)
1135
{
2125 decky 1136
#ifdef __OBJC__
1137
    return [as_t page_table_destroy: page_table];
1138
#else
1139
    ASSERT(as_operations);
1140
    ASSERT(as_operations->page_table_destroy);
1141
 
1142
    as_operations->page_table_destroy(page_table);
1143
#endif
1468 jermar 1144
}
1145
 
1044 jermar 1146
/** Lock page table.
1147
 *
1148
 * This function should be called before any page_mapping_insert(),
1149
 * page_mapping_remove() and page_mapping_find().
1150
 *
1151
 * Locking order is such that address space areas must be locked
1152
 * prior to this call. Address space can be locked prior to this
1153
 * call in which case the lock argument is false.
1154
 *
1155
 * @param as Address space.
1248 jermar 1156
 * @param lock If false, do not attempt to lock as->lock.
1044 jermar 1157
 */
1158
void page_table_lock(as_t *as, bool lock)
1159
{
2125 decky 1160
#ifdef __OBJC__
1161
    [as page_table_lock: lock];
1162
#else
1044 jermar 1163
    ASSERT(as_operations);
1164
    ASSERT(as_operations->page_table_lock);
2125 decky 1165
 
1044 jermar 1166
    as_operations->page_table_lock(as, lock);
2125 decky 1167
#endif
1044 jermar 1168
}
1169
 
1170
/** Unlock page table.
1171
 *
1172
 * @param as Address space.
1248 jermar 1173
 * @param unlock If false, do not attempt to unlock as->lock.
1044 jermar 1174
 */
1175
void page_table_unlock(as_t *as, bool unlock)
1176
{
2125 decky 1177
#ifdef __OBJC__
1178
    [as page_table_unlock: unlock];
1179
#else
1044 jermar 1180
    ASSERT(as_operations);
1181
    ASSERT(as_operations->page_table_unlock);
2125 decky 1182
 
1044 jermar 1183
    as_operations->page_table_unlock(as, unlock);
2125 decky 1184
#endif
1044 jermar 1185
}
1186
 
977 jermar 1187
 
1188
/** Find address space area and lock it.
1189
 *
1190
 * The address space must be locked and interrupts must be disabled.
1191
 *
1192
 * @param as Address space.
1193
 * @param va Virtual address.
1194
 *
2087 jermar 1195
 * @return Locked address space area containing va on success or NULL on
1196
 *     failure.
977 jermar 1197
 */
1780 jermar 1198
as_area_t *find_area_and_lock(as_t *as, uintptr_t va)
977 jermar 1199
{
1200
    as_area_t *a;
1147 jermar 1201
    btree_node_t *leaf, *lnode;
2745 decky 1202
    unsigned int i;
977 jermar 1203
 
1147 jermar 1204
    a = (as_area_t *) btree_search(&as->as_area_btree, va, &leaf);
1205
    if (a) {
1206
        /* va is the base address of an address space area */
1380 jermar 1207
        mutex_lock(&a->lock);
1147 jermar 1208
        return a;
1209
    }
1210
 
1211
    /*
1150 jermar 1212
     * Search the leaf node and the righmost record of its left neighbour
1147 jermar 1213
     * to find out whether this is a miss or va belongs to an address
1214
     * space area found there.
1215
     */
1216
 
1217
    /* First, search the leaf node itself. */
1218
    for (i = 0; i < leaf->keys; i++) {
1219
        a = (as_area_t *) leaf->value[i];
1380 jermar 1220
        mutex_lock(&a->lock);
1147 jermar 1221
        if ((a->base <= va) && (va < a->base + a->pages * PAGE_SIZE)) {
1222
            return a;
1223
        }
1380 jermar 1224
        mutex_unlock(&a->lock);
1147 jermar 1225
    }
977 jermar 1226
 
1147 jermar 1227
    /*
1150 jermar 1228
     * Second, locate the left neighbour and test its last record.
1148 jermar 1229
     * Because of its position in the B+tree, it must have base < va.
1147 jermar 1230
     */
2087 jermar 1231
    lnode = btree_leaf_node_left_neighbour(&as->as_area_btree, leaf);
1232
    if (lnode) {
1147 jermar 1233
        a = (as_area_t *) lnode->value[lnode->keys - 1];
1380 jermar 1234
        mutex_lock(&a->lock);
1147 jermar 1235
        if (va < a->base + a->pages * PAGE_SIZE) {
1048 jermar 1236
            return a;
1147 jermar 1237
        }
1380 jermar 1238
        mutex_unlock(&a->lock);
977 jermar 1239
    }
1240
 
1241
    return NULL;
1242
}
1048 jermar 1243
 
1244
/** Check area conflicts with other areas.
1245
 *
1246
 * The address space must be locked and interrupts must be disabled.
1247
 *
1248
 * @param as Address space.
1249
 * @param va Starting virtual address of the area being tested.
1250
 * @param size Size of the area being tested.
1251
 * @param avoid_area Do not touch this area.
1252
 *
1253
 * @return True if there is no conflict, false otherwise.
1254
 */
2087 jermar 1255
bool check_area_conflicts(as_t *as, uintptr_t va, size_t size,
1256
              as_area_t *avoid_area)
1048 jermar 1257
{
1258
    as_area_t *a;
1147 jermar 1259
    btree_node_t *leaf, *node;
2745 decky 1260
    unsigned int i;
1048 jermar 1261
 
1070 jermar 1262
    /*
1263
     * We don't want any area to have conflicts with NULL page.
1264
     */
1265
    if (overlaps(va, size, NULL, PAGE_SIZE))
1266
        return false;
1267
 
1147 jermar 1268
    /*
1269
     * The leaf node is found in O(log n), where n is proportional to
1270
     * the number of address space areas belonging to as.
1271
     * The check for conflicts is then attempted on the rightmost
1150 jermar 1272
     * record in the left neighbour, the leftmost record in the right
1273
     * neighbour and all records in the leaf node itself.
1147 jermar 1274
     */
1048 jermar 1275
 
1147 jermar 1276
    if ((a = (as_area_t *) btree_search(&as->as_area_btree, va, &leaf))) {
1277
        if (a != avoid_area)
1278
            return false;
1279
    }
1280
 
1281
    /* First, check the two border cases. */
1150 jermar 1282
    if ((node = btree_leaf_node_left_neighbour(&as->as_area_btree, leaf))) {
1147 jermar 1283
        a = (as_area_t *) node->value[node->keys - 1];
1380 jermar 1284
        mutex_lock(&a->lock);
1147 jermar 1285
        if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
1380 jermar 1286
            mutex_unlock(&a->lock);
1147 jermar 1287
            return false;
1288
        }
1380 jermar 1289
        mutex_unlock(&a->lock);
1147 jermar 1290
    }
2087 jermar 1291
    node = btree_leaf_node_right_neighbour(&as->as_area_btree, leaf);
1292
    if (node) {
1147 jermar 1293
        a = (as_area_t *) node->value[0];
1380 jermar 1294
        mutex_lock(&a->lock);
1147 jermar 1295
        if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
1380 jermar 1296
            mutex_unlock(&a->lock);
1147 jermar 1297
            return false;
1298
        }
1380 jermar 1299
        mutex_unlock(&a->lock);
1147 jermar 1300
    }
1301
 
1302
    /* Second, check the leaf node. */
1303
    for (i = 0; i < leaf->keys; i++) {
1304
        a = (as_area_t *) leaf->value[i];
1305
 
1048 jermar 1306
        if (a == avoid_area)
1307
            continue;
1147 jermar 1308
 
1380 jermar 1309
        mutex_lock(&a->lock);
1147 jermar 1310
        if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
1380 jermar 1311
            mutex_unlock(&a->lock);
1147 jermar 1312
            return false;
1313
        }
1380 jermar 1314
        mutex_unlock(&a->lock);
1048 jermar 1315
    }
1316
 
1070 jermar 1317
    /*
1318
     * So far, the area does not conflict with other areas.
1319
     * Check if it doesn't conflict with kernel address space.
1320
     */  
1321
    if (!KERNEL_ADDRESS_SPACE_SHADOWED) {
1322
        return !overlaps(va, size,
2087 jermar 1323
            KERNEL_ADDRESS_SPACE_START,
1324
            KERNEL_ADDRESS_SPACE_END - KERNEL_ADDRESS_SPACE_START);
1070 jermar 1325
    }
1326
 
1048 jermar 1327
    return true;
1328
}
1235 jermar 1329
 
2556 jermar 1330
/** Return size of the address space area with given base.
1331
 *
1332
 * @param base      Arbitrary address insede the address space area.
1333
 *
1334
 * @return      Size of the address space area in bytes or zero if it
1335
 *          does not exist.
1336
 */
1337
size_t as_area_get_size(uintptr_t base)
1329 palkovsky 1338
{
1339
    ipl_t ipl;
1340
    as_area_t *src_area;
1341
    size_t size;
1342
 
1343
    ipl = interrupts_disable();
1344
    src_area = find_area_and_lock(AS, base);
1345
    if (src_area){
1346
        size = src_area->pages * PAGE_SIZE;
1380 jermar 1347
        mutex_unlock(&src_area->lock);
1329 palkovsky 1348
    } else {
1349
        size = 0;
1350
    }
1351
    interrupts_restore(ipl);
1352
    return size;
1353
}
1354
 
1387 jermar 1355
/** Mark portion of address space area as used.
1356
 *
1357
 * The address space area must be already locked.
1358
 *
1359
 * @param a Address space area.
1360
 * @param page First page to be marked.
1361
 * @param count Number of page to be marked.
1362
 *
1363
 * @return 0 on failure and 1 on success.
1364
 */
1780 jermar 1365
int used_space_insert(as_area_t *a, uintptr_t page, count_t count)
1387 jermar 1366
{
1367
    btree_node_t *leaf, *node;
1368
    count_t pages;
2745 decky 1369
    unsigned int i;
1387 jermar 1370
 
1371
    ASSERT(page == ALIGN_DOWN(page, PAGE_SIZE));
1372
    ASSERT(count);
1373
 
1374
    pages = (count_t) btree_search(&a->used_space, page, &leaf);
1375
    if (pages) {
1376
        /*
1377
         * We hit the beginning of some used space.
1378
         */
1379
        return 0;
1380
    }
1381
 
1437 jermar 1382
    if (!leaf->keys) {
1383
        btree_insert(&a->used_space, page, (void *) count, leaf);
1384
        return 1;
1385
    }
1386
 
1387 jermar 1387
    node = btree_leaf_node_left_neighbour(&a->used_space, leaf);
1388
    if (node) {
2087 jermar 1389
        uintptr_t left_pg = node->key[node->keys - 1];
1390
        uintptr_t right_pg = leaf->key[0];
1391
        count_t left_cnt = (count_t) node->value[node->keys - 1];
1392
        count_t right_cnt = (count_t) leaf->value[0];
1387 jermar 1393
 
1394
        /*
1395
         * Examine the possibility that the interval fits
1396
         * somewhere between the rightmost interval of
1397
         * the left neigbour and the first interval of the leaf.
1398
         */
1399
 
1400
        if (page >= right_pg) {
1401
            /* Do nothing. */
2087 jermar 1402
        } else if (overlaps(page, count * PAGE_SIZE, left_pg,
1403
            left_cnt * PAGE_SIZE)) {
1387 jermar 1404
            /* The interval intersects with the left interval. */
1405
            return 0;
2087 jermar 1406
        } else if (overlaps(page, count * PAGE_SIZE, right_pg,
1407
            right_cnt * PAGE_SIZE)) {
1387 jermar 1408
            /* The interval intersects with the right interval. */
1409
            return 0;          
2087 jermar 1410
        } else if ((page == left_pg + left_cnt * PAGE_SIZE) &&
1411
            (page + count * PAGE_SIZE == right_pg)) {
1412
            /*
1413
             * The interval can be added by merging the two already
1414
             * present intervals.
1415
             */
1403 jermar 1416
            node->value[node->keys - 1] += count + right_cnt;
1387 jermar 1417
            btree_remove(&a->used_space, right_pg, leaf);
1418
            return 1;
2087 jermar 1419
        } else if (page == left_pg + left_cnt * PAGE_SIZE) {
1420
            /*
1421
             * The interval can be added by simply growing the left
1422
             * interval.
1423
             */
1403 jermar 1424
            node->value[node->keys - 1] += count;
1387 jermar 1425
            return 1;
2087 jermar 1426
        } else if (page + count * PAGE_SIZE == right_pg) {
1387 jermar 1427
            /*
2087 jermar 1428
             * The interval can be addded by simply moving base of
1429
             * the right interval down and increasing its size
1430
             * accordingly.
1387 jermar 1431
             */
1403 jermar 1432
            leaf->value[0] += count;
1387 jermar 1433
            leaf->key[0] = page;
1434
            return 1;
1435
        } else {
1436
            /*
1437
             * The interval is between both neigbouring intervals,
1438
             * but cannot be merged with any of them.
1439
             */
2087 jermar 1440
            btree_insert(&a->used_space, page, (void *) count,
1441
                leaf);
1387 jermar 1442
            return 1;
1443
        }
1444
    } else if (page < leaf->key[0]) {
1780 jermar 1445
        uintptr_t right_pg = leaf->key[0];
1387 jermar 1446
        count_t right_cnt = (count_t) leaf->value[0];
1447
 
1448
        /*
2087 jermar 1449
         * Investigate the border case in which the left neighbour does
1450
         * not exist but the interval fits from the left.
1387 jermar 1451
         */
1452
 
2087 jermar 1453
        if (overlaps(page, count * PAGE_SIZE, right_pg,
1454
            right_cnt * PAGE_SIZE)) {
1387 jermar 1455
            /* The interval intersects with the right interval. */
1456
            return 0;
2087 jermar 1457
        } else if (page + count * PAGE_SIZE == right_pg) {
1387 jermar 1458
            /*
2087 jermar 1459
             * The interval can be added by moving the base of the
1460
             * right interval down and increasing its size
1461
             * accordingly.
1387 jermar 1462
             */
1463
            leaf->key[0] = page;
1403 jermar 1464
            leaf->value[0] += count;
1387 jermar 1465
            return 1;
1466
        } else {
1467
            /*
1468
             * The interval doesn't adjoin with the right interval.
1469
             * It must be added individually.
1470
             */
2087 jermar 1471
            btree_insert(&a->used_space, page, (void *) count,
1472
                leaf);
1387 jermar 1473
            return 1;
1474
        }
1475
    }
1476
 
1477
    node = btree_leaf_node_right_neighbour(&a->used_space, leaf);
1478
    if (node) {
2087 jermar 1479
        uintptr_t left_pg = leaf->key[leaf->keys - 1];
1480
        uintptr_t right_pg = node->key[0];
1481
        count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
1482
        count_t right_cnt = (count_t) node->value[0];
1387 jermar 1483
 
1484
        /*
1485
         * Examine the possibility that the interval fits
1486
         * somewhere between the leftmost interval of
1487
         * the right neigbour and the last interval of the leaf.
1488
         */
1489
 
1490
        if (page < left_pg) {
1491
            /* Do nothing. */
2087 jermar 1492
        } else if (overlaps(page, count * PAGE_SIZE, left_pg,
1493
            left_cnt * PAGE_SIZE)) {
1387 jermar 1494
            /* The interval intersects with the left interval. */
1495
            return 0;
2087 jermar 1496
        } else if (overlaps(page, count * PAGE_SIZE, right_pg,
1497
            right_cnt * PAGE_SIZE)) {
1387 jermar 1498
            /* The interval intersects with the right interval. */
1499
            return 0;          
2087 jermar 1500
        } else if ((page == left_pg + left_cnt * PAGE_SIZE) &&
1501
            (page + count * PAGE_SIZE == right_pg)) {
1502
            /*
1503
             * The interval can be added by merging the two already
1504
             * present intervals.
1505
             * */
1403 jermar 1506
            leaf->value[leaf->keys - 1] += count + right_cnt;
1387 jermar 1507
            btree_remove(&a->used_space, right_pg, node);
1508
            return 1;
2087 jermar 1509
        } else if (page == left_pg + left_cnt * PAGE_SIZE) {
1510
            /*
1511
             * The interval can be added by simply growing the left
1512
             * interval.
1513
             * */
1403 jermar 1514
            leaf->value[leaf->keys - 1] +=  count;
1387 jermar 1515
            return 1;
2087 jermar 1516
        } else if (page + count * PAGE_SIZE == right_pg) {
1387 jermar 1517
            /*
2087 jermar 1518
             * The interval can be addded by simply moving base of
1519
             * the right interval down and increasing its size
1520
             * accordingly.
1387 jermar 1521
             */
1403 jermar 1522
            node->value[0] += count;
1387 jermar 1523
            node->key[0] = page;
1524
            return 1;
1525
        } else {
1526
            /*
1527
             * The interval is between both neigbouring intervals,
1528
             * but cannot be merged with any of them.
1529
             */
2087 jermar 1530
            btree_insert(&a->used_space, page, (void *) count,
1531
                leaf);
1387 jermar 1532
            return 1;
1533
        }
1534
    } else if (page >= leaf->key[leaf->keys - 1]) {
1780 jermar 1535
        uintptr_t left_pg = leaf->key[leaf->keys - 1];
1387 jermar 1536
        count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
1537
 
1538
        /*
2087 jermar 1539
         * Investigate the border case in which the right neighbour
1540
         * does not exist but the interval fits from the right.
1387 jermar 1541
         */
1542
 
2087 jermar 1543
        if (overlaps(page, count * PAGE_SIZE, left_pg,
1544
            left_cnt * PAGE_SIZE)) {
1403 jermar 1545
            /* The interval intersects with the left interval. */
1387 jermar 1546
            return 0;
2087 jermar 1547
        } else if (left_pg + left_cnt * PAGE_SIZE == page) {
1548
            /*
1549
             * The interval can be added by growing the left
1550
             * interval.
1551
             */
1403 jermar 1552
            leaf->value[leaf->keys - 1] += count;
1387 jermar 1553
            return 1;
1554
        } else {
1555
            /*
1556
             * The interval doesn't adjoin with the left interval.
1557
             * It must be added individually.
1558
             */
2087 jermar 1559
            btree_insert(&a->used_space, page, (void *) count,
1560
                leaf);
1387 jermar 1561
            return 1;
1562
        }
1563
    }
1564
 
1565
    /*
2087 jermar 1566
     * Note that if the algorithm made it thus far, the interval can fit
1567
     * only between two other intervals of the leaf. The two border cases
1568
     * were already resolved.
1387 jermar 1569
     */
1570
    for (i = 1; i < leaf->keys; i++) {
1571
        if (page < leaf->key[i]) {
2087 jermar 1572
            uintptr_t left_pg = leaf->key[i - 1];
1573
            uintptr_t right_pg = leaf->key[i];
1574
            count_t left_cnt = (count_t) leaf->value[i - 1];
1575
            count_t right_cnt = (count_t) leaf->value[i];
1387 jermar 1576
 
1577
            /*
1578
             * The interval fits between left_pg and right_pg.
1579
             */
1580
 
2087 jermar 1581
            if (overlaps(page, count * PAGE_SIZE, left_pg,
1582
                left_cnt * PAGE_SIZE)) {
1583
                /*
1584
                 * The interval intersects with the left
1585
                 * interval.
1586
                 */
1387 jermar 1587
                return 0;
2087 jermar 1588
            } else if (overlaps(page, count * PAGE_SIZE, right_pg,
1589
                right_cnt * PAGE_SIZE)) {
1590
                /*
1591
                 * The interval intersects with the right
1592
                 * interval.
1593
                 */
1387 jermar 1594
                return 0;          
2087 jermar 1595
            } else if ((page == left_pg + left_cnt * PAGE_SIZE) &&
1596
                (page + count * PAGE_SIZE == right_pg)) {
1597
                /*
1598
                 * The interval can be added by merging the two
1599
                 * already present intervals.
1600
                 */
1403 jermar 1601
                leaf->value[i - 1] += count + right_cnt;
1387 jermar 1602
                btree_remove(&a->used_space, right_pg, leaf);
1603
                return 1;
2087 jermar 1604
            } else if (page == left_pg + left_cnt * PAGE_SIZE) {
1605
                /*
1606
                 * The interval can be added by simply growing
1607
                 * the left interval.
1608
                 */
1403 jermar 1609
                leaf->value[i - 1] += count;
1387 jermar 1610
                return 1;
2087 jermar 1611
            } else if (page + count * PAGE_SIZE == right_pg) {
1387 jermar 1612
                /*
2087 jermar 1613
                     * The interval can be addded by simply moving
1614
                 * base of the right interval down and
1615
                 * increasing its size accordingly.
1387 jermar 1616
                 */
1403 jermar 1617
                leaf->value[i] += count;
1387 jermar 1618
                leaf->key[i] = page;
1619
                return 1;
1620
            } else {
1621
                /*
2087 jermar 1622
                 * The interval is between both neigbouring
1623
                 * intervals, but cannot be merged with any of
1624
                 * them.
1387 jermar 1625
                 */
2087 jermar 1626
                btree_insert(&a->used_space, page,
1627
                    (void *) count, leaf);
1387 jermar 1628
                return 1;
1629
            }
1630
        }
1631
    }
1632
 
2087 jermar 1633
    panic("Inconsistency detected while adding %d pages of used space at "
1634
        "%p.\n", count, page);
1387 jermar 1635
}
1636
 
1637
/** Mark portion of address space area as unused.
1638
 *
1639
 * The address space area must be already locked.
1640
 *
1641
 * @param a Address space area.
1642
 * @param page First page to be marked.
1643
 * @param count Number of page to be marked.
1644
 *
1645
 * @return 0 on failure and 1 on success.
1646
 */
1780 jermar 1647
int used_space_remove(as_area_t *a, uintptr_t page, count_t count)
1387 jermar 1648
{
1649
    btree_node_t *leaf, *node;
1650
    count_t pages;
2745 decky 1651
    unsigned int i;
1387 jermar 1652
 
1653
    ASSERT(page == ALIGN_DOWN(page, PAGE_SIZE));
1654
    ASSERT(count);
1655
 
1656
    pages = (count_t) btree_search(&a->used_space, page, &leaf);
1657
    if (pages) {
1658
        /*
1659
         * We are lucky, page is the beginning of some interval.
1660
         */
1661
        if (count > pages) {
1662
            return 0;
1663
        } else if (count == pages) {
1664
            btree_remove(&a->used_space, page, leaf);
1403 jermar 1665
            return 1;
1387 jermar 1666
        } else {
1667
            /*
1668
             * Find the respective interval.
1669
             * Decrease its size and relocate its start address.
1670
             */
1671
            for (i = 0; i < leaf->keys; i++) {
1672
                if (leaf->key[i] == page) {
2087 jermar 1673
                    leaf->key[i] += count * PAGE_SIZE;
1403 jermar 1674
                    leaf->value[i] -= count;
1387 jermar 1675
                    return 1;
1676
                }
1677
            }
1678
            goto error;
1679
        }
1680
    }
1681
 
1682
    node = btree_leaf_node_left_neighbour(&a->used_space, leaf);
1683
    if (node && page < leaf->key[0]) {
1780 jermar 1684
        uintptr_t left_pg = node->key[node->keys - 1];
1387 jermar 1685
        count_t left_cnt = (count_t) node->value[node->keys - 1];
1686
 
2087 jermar 1687
        if (overlaps(left_pg, left_cnt * PAGE_SIZE, page,
1688
            count * PAGE_SIZE)) {
1689
            if (page + count * PAGE_SIZE ==
1690
                left_pg + left_cnt * PAGE_SIZE) {
1387 jermar 1691
                /*
2087 jermar 1692
                 * The interval is contained in the rightmost
1693
                 * interval of the left neighbour and can be
1694
                 * removed by updating the size of the bigger
1695
                 * interval.
1387 jermar 1696
                 */
1403 jermar 1697
                node->value[node->keys - 1] -= count;
1387 jermar 1698
                return 1;
2087 jermar 1699
            } else if (page + count * PAGE_SIZE <
1700
                left_pg + left_cnt*PAGE_SIZE) {
1403 jermar 1701
                count_t new_cnt;
1387 jermar 1702
 
1703
                /*
2087 jermar 1704
                 * The interval is contained in the rightmost
1705
                 * interval of the left neighbour but its
1706
                 * removal requires both updating the size of
1707
                 * the original interval and also inserting a
1708
                 * new interval.
1387 jermar 1709
                 */
2087 jermar 1710
                new_cnt = ((left_pg + left_cnt * PAGE_SIZE) -
1711
                    (page + count*PAGE_SIZE)) >> PAGE_WIDTH;
1403 jermar 1712
                node->value[node->keys - 1] -= count + new_cnt;
2087 jermar 1713
                btree_insert(&a->used_space, page +
1714
                    count * PAGE_SIZE, (void *) new_cnt, leaf);
1387 jermar 1715
                return 1;
1716
            }
1717
        }
1718
        return 0;
1719
    } else if (page < leaf->key[0]) {
1720
        return 0;
1721
    }
1722
 
1723
    if (page > leaf->key[leaf->keys - 1]) {
1780 jermar 1724
        uintptr_t left_pg = leaf->key[leaf->keys - 1];
1387 jermar 1725
        count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
1726
 
2087 jermar 1727
        if (overlaps(left_pg, left_cnt * PAGE_SIZE, page,
1728
            count * PAGE_SIZE)) {
1729
            if (page + count * PAGE_SIZE ==
1730
                left_pg + left_cnt * PAGE_SIZE) {
1387 jermar 1731
                /*
2087 jermar 1732
                 * The interval is contained in the rightmost
1733
                 * interval of the leaf and can be removed by
1734
                 * updating the size of the bigger interval.
1387 jermar 1735
                 */
1403 jermar 1736
                leaf->value[leaf->keys - 1] -= count;
1387 jermar 1737
                return 1;
2087 jermar 1738
            } else if (page + count * PAGE_SIZE < left_pg +
1739
                left_cnt * PAGE_SIZE) {
1403 jermar 1740
                count_t new_cnt;
1387 jermar 1741
 
1742
                /*
2087 jermar 1743
                 * The interval is contained in the rightmost
1744
                 * interval of the leaf but its removal
1745
                 * requires both updating the size of the
1746
                 * original interval and also inserting a new
1747
                 * interval.
1387 jermar 1748
                 */
2087 jermar 1749
                new_cnt = ((left_pg + left_cnt * PAGE_SIZE) -
1750
                    (page + count * PAGE_SIZE)) >> PAGE_WIDTH;
1403 jermar 1751
                leaf->value[leaf->keys - 1] -= count + new_cnt;
2087 jermar 1752
                btree_insert(&a->used_space, page +
1753
                    count * PAGE_SIZE, (void *) new_cnt, leaf);
1387 jermar 1754
                return 1;
1755
            }
1756
        }
1757
        return 0;
1758
    }  
1759
 
1760
    /*
1761
     * The border cases have been already resolved.
1762
     * Now the interval can be only between intervals of the leaf.
1763
     */
1764
    for (i = 1; i < leaf->keys - 1; i++) {
1765
        if (page < leaf->key[i]) {
1780 jermar 1766
            uintptr_t left_pg = leaf->key[i - 1];
1387 jermar 1767
            count_t left_cnt = (count_t) leaf->value[i - 1];
1768
 
1769
            /*
2087 jermar 1770
             * Now the interval is between intervals corresponding
1771
             * to (i - 1) and i.
1387 jermar 1772
             */
2087 jermar 1773
            if (overlaps(left_pg, left_cnt * PAGE_SIZE, page,
1774
                count * PAGE_SIZE)) {
1775
                if (page + count * PAGE_SIZE ==
1776
                    left_pg + left_cnt*PAGE_SIZE) {
1387 jermar 1777
                    /*
2087 jermar 1778
                     * The interval is contained in the
1779
                     * interval (i - 1) of the leaf and can
1780
                     * be removed by updating the size of
1781
                     * the bigger interval.
1387 jermar 1782
                     */
1403 jermar 1783
                    leaf->value[i - 1] -= count;
1387 jermar 1784
                    return 1;
2087 jermar 1785
                } else if (page + count * PAGE_SIZE <
1786
                    left_pg + left_cnt * PAGE_SIZE) {
1403 jermar 1787
                    count_t new_cnt;
1387 jermar 1788
 
1789
                    /*
2087 jermar 1790
                     * The interval is contained in the
1791
                     * interval (i - 1) of the leaf but its
1792
                     * removal requires both updating the
1793
                     * size of the original interval and
1387 jermar 1794
                     * also inserting a new interval.
1795
                     */
2087 jermar 1796
                    new_cnt = ((left_pg +
1797
                        left_cnt * PAGE_SIZE) -
1798
                        (page + count * PAGE_SIZE)) >>
1799
                        PAGE_WIDTH;
1403 jermar 1800
                    leaf->value[i - 1] -= count + new_cnt;
2087 jermar 1801
                    btree_insert(&a->used_space, page +
1802
                        count * PAGE_SIZE, (void *) new_cnt,
1803
                        leaf);
1387 jermar 1804
                    return 1;
1805
                }
1806
            }
1807
            return 0;
1808
        }
1809
    }
1810
 
1811
error:
2087 jermar 1812
    panic("Inconsistency detected while removing %d pages of used space "
1813
        "from %p.\n", count, page);
1387 jermar 1814
}
1815
 
1409 jermar 1816
/** Remove reference to address space area share info.
1817
 *
1818
 * If the reference count drops to 0, the sh_info is deallocated.
1819
 *
1820
 * @param sh_info Pointer to address space area share info.
1821
 */
1822
void sh_info_remove_reference(share_info_t *sh_info)
1823
{
1824
    bool dealloc = false;
1825
 
1826
    mutex_lock(&sh_info->lock);
1827
    ASSERT(sh_info->refcount);
1828
    if (--sh_info->refcount == 0) {
1829
        dealloc = true;
1495 jermar 1830
        link_t *cur;
1409 jermar 1831
 
1832
        /*
1833
         * Now walk carefully the pagemap B+tree and free/remove
1834
         * reference from all frames found there.
1835
         */
2087 jermar 1836
        for (cur = sh_info->pagemap.leaf_head.next;
1837
            cur != &sh_info->pagemap.leaf_head; cur = cur->next) {
1409 jermar 1838
            btree_node_t *node;
2745 decky 1839
            unsigned int i;
1409 jermar 1840
 
1495 jermar 1841
            node = list_get_instance(cur, btree_node_t, leaf_link);
1842
            for (i = 0; i < node->keys; i++)
1780 jermar 1843
                frame_free((uintptr_t) node->value[i]);
1409 jermar 1844
        }
1845
 
1846
    }
1847
    mutex_unlock(&sh_info->lock);
1848
 
1849
    if (dealloc) {
1850
        btree_destroy(&sh_info->pagemap);
1851
        free(sh_info);
1852
    }
1853
}
1854
 
1235 jermar 1855
/*
1856
 * Address space related syscalls.
1857
 */
1858
 
1859
/** Wrapper for as_area_create(). */
1780 jermar 1860
unative_t sys_as_area_create(uintptr_t address, size_t size, int flags)
1235 jermar 1861
{
2087 jermar 1862
    if (as_area_create(AS, flags | AS_AREA_CACHEABLE, size, address,
1863
        AS_AREA_ATTR_NONE, &anon_backend, NULL))
1780 jermar 1864
        return (unative_t) address;
1235 jermar 1865
    else
1780 jermar 1866
        return (unative_t) -1;
1235 jermar 1867
}
1868
 
1793 jermar 1869
/** Wrapper for as_area_resize(). */
1780 jermar 1870
unative_t sys_as_area_resize(uintptr_t address, size_t size, int flags)
1235 jermar 1871
{
1780 jermar 1872
    return (unative_t) as_area_resize(AS, address, size, 0);
1235 jermar 1873
}
1874
 
2984 svoboda 1875
/** Wrapper for as_area_change_flags(). */
1876
unative_t sys_as_area_change_flags(uintptr_t address, int flags)
1877
{
1878
    return (unative_t) as_area_change_flags(AS, flags, address);
1879
}
1880
 
1793 jermar 1881
/** Wrapper for as_area_destroy(). */
1780 jermar 1882
unative_t sys_as_area_destroy(uintptr_t address)
1306 jermar 1883
{
1780 jermar 1884
    return (unative_t) as_area_destroy(AS, address);
1306 jermar 1885
}
1702 cejka 1886
 
1914 jermar 1887
/** Print out information about address space.
1888
 *
1889
 * @param as Address space.
1890
 */
1891
void as_print(as_t *as)
1892
{
1893
    ipl_t ipl;
1894
 
1895
    ipl = interrupts_disable();
1896
    mutex_lock(&as->lock);
1897
 
1898
    /* print out info about address space areas */
1899
    link_t *cur;
2087 jermar 1900
    for (cur = as->as_area_btree.leaf_head.next;
1901
        cur != &as->as_area_btree.leaf_head; cur = cur->next) {
1902
        btree_node_t *node;
1914 jermar 1903
 
2087 jermar 1904
        node = list_get_instance(cur, btree_node_t, leaf_link);
1905
 
2745 decky 1906
        unsigned int i;
1914 jermar 1907
        for (i = 0; i < node->keys; i++) {
1915 jermar 1908
            as_area_t *area = node->value[i];
1914 jermar 1909
 
1910
            mutex_lock(&area->lock);
1911
            printf("as_area: %p, base=%p, pages=%d (%p - %p)\n",
2087 jermar 1912
                area, area->base, area->pages, area->base,
1913
                area->base + area->pages*PAGE_SIZE);
1914 jermar 1914
            mutex_unlock(&area->lock);
1915
        }
1916
    }
1917
 
1918
    mutex_unlock(&as->lock);
1919
    interrupts_restore(ipl);
1920
}
1921
 
1757 jermar 1922
/** @}
1702 cejka 1923
 */