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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
 
1757 jermar 85
/**
86
 * Each architecture decides what functions will be used to carry out
87
 * address space operations such as creating or locking page tables.
88
 */
756 jermar 89
as_operations_t *as_operations = NULL;
703 jermar 90
 
1890 jermar 91
/**
92
 * Slab for as_t objects.
93
 */
94
static slab_cache_t *as_slab;
95
 
2087 jermar 96
/**
2170 jermar 97
 * This lock serializes access to the ASID subsystem.
98
 * It protects:
99
 * - inactive_as_with_asid_head list
100
 * - as->asid for each as of the as_t type
101
 * - asids_allocated counter
2087 jermar 102
 */
2170 jermar 103
SPINLOCK_INITIALIZE(asidlock);
823 jermar 104
 
105
/**
106
 * This list contains address spaces that are not active on any
107
 * processor and that have valid ASID.
108
 */
109
LIST_INITIALIZE(inactive_as_with_asid_head);
110
 
757 jermar 111
/** Kernel address space. */
112
as_t *AS_KERNEL = NULL;
113
 
3425 svoboda 114
static int area_flags_to_page_flags(int);
115
static bool check_area_conflicts(as_t *, uintptr_t, size_t, as_area_t *);
116
static void sh_info_remove_reference(share_info_t *);
703 jermar 117
 
1891 jermar 118
static int as_constructor(void *obj, int flags)
119
{
120
    as_t *as = (as_t *) obj;
121
    int rc;
122
 
123
    link_initialize(&as->inactive_as_with_asid_link);
4377 svoboda 124
    mutex_initialize(&as->lock, MUTEX_PASSIVE);
1891 jermar 125
 
126
    rc = as_constructor_arch(as, flags);
127
 
128
    return rc;
129
}
130
 
131
static int as_destructor(void *obj)
132
{
133
    as_t *as = (as_t *) obj;
134
 
135
    return as_destructor_arch(as);
136
}
137
 
756 jermar 138
/** Initialize address space subsystem. */
139
void as_init(void)
140
{
141
    as_arch_init();
2126 decky 142
 
1891 jermar 143
    as_slab = slab_cache_create("as_slab", sizeof(as_t), 0,
2087 jermar 144
        as_constructor, as_destructor, SLAB_CACHE_MAGDEFERRED);
1890 jermar 145
 
789 palkovsky 146
    AS_KERNEL = as_create(FLAG_AS_KERNEL);
1383 decky 147
    if (!AS_KERNEL)
4377 svoboda 148
        panic("Cannot create kernel address space.");
1383 decky 149
 
4377 svoboda 150
    /* Make sure the kernel address space
151
     * reference count never drops to zero.
152
     */
153
    atomic_set(&AS_KERNEL->refcount, 1);
756 jermar 154
}
155
 
757 jermar 156
/** Create address space.
157
 *
3425 svoboda 158
 * @param flags     Flags that influence the way in wich the address space
159
 *          is created.
757 jermar 160
 */
756 jermar 161
as_t *as_create(int flags)
703 jermar 162
{
163
    as_t *as;
164
 
1890 jermar 165
    as = (as_t *) slab_alloc(as_slab, 0);
1891 jermar 166
    (void) as_create_arch(as, 0);
167
 
1147 jermar 168
    btree_create(&as->as_area_btree);
822 palkovsky 169
 
170
    if (flags & FLAG_AS_KERNEL)
171
        as->asid = ASID_KERNEL;
172
    else
173
        as->asid = ASID_INVALID;
174
 
2183 jermar 175
    atomic_set(&as->refcount, 0);
1415 jermar 176
    as->cpu_refcount = 0;
2089 decky 177
#ifdef AS_PAGE_TABLE
2106 jermar 178
    as->genarch.page_table = page_table_create(flags);
2089 decky 179
#else
180
    page_table_create(flags);
181
#endif
4377 svoboda 182
 
703 jermar 183
    return as;
184
}
185
 
1468 jermar 186
/** Destroy adress space.
187
 *
2087 jermar 188
 * When there are no tasks referencing this address space (i.e. its refcount is
189
 * zero), the address space can be destroyed.
2183 jermar 190
 *
191
 * We know that we don't hold any spinlock.
3425 svoboda 192
 *
193
 * @param as        Address space to be destroyed.
1468 jermar 194
 */
195
void as_destroy(as_t *as)
973 palkovsky 196
{
1468 jermar 197
    ipl_t ipl;
1594 jermar 198
    bool cond;
2183 jermar 199
    DEADLOCK_PROBE_INIT(p_asidlock);
973 palkovsky 200
 
2183 jermar 201
    ASSERT(atomic_get(&as->refcount) == 0);
1468 jermar 202
 
203
    /*
204
     * Since there is no reference to this area,
205
     * it is safe not to lock its mutex.
206
     */
2170 jermar 207
 
2183 jermar 208
    /*
209
     * We need to avoid deadlock between TLB shootdown and asidlock.
210
     * We therefore try to take asid conditionally and if we don't succeed,
211
     * we enable interrupts and try again. This is done while preemption is
212
     * disabled to prevent nested context switches. We also depend on the
213
     * fact that so far no spinlocks are held.
214
     */
215
    preemption_disable();
216
    ipl = interrupts_read();
217
retry:
218
    interrupts_disable();
219
    if (!spinlock_trylock(&asidlock)) {
220
        interrupts_enable();
221
        DEADLOCK_PROBE(p_asidlock, DEADLOCK_THRESHOLD);
222
        goto retry;
223
    }
224
    preemption_enable();    /* Interrupts disabled, enable preemption */
1587 jermar 225
    if (as->asid != ASID_INVALID && as != AS_KERNEL) {
1594 jermar 226
        if (as != AS && as->cpu_refcount == 0)
1587 jermar 227
            list_remove(&as->inactive_as_with_asid_link);
1468 jermar 228
        asid_put(as->asid);
229
    }
2170 jermar 230
    spinlock_unlock(&asidlock);
1468 jermar 231
 
232
    /*
233
     * Destroy address space areas of the address space.
1954 jermar 234
     * The B+tree must be walked carefully because it is
1594 jermar 235
     * also being destroyed.
1468 jermar 236
     */
1594 jermar 237
    for (cond = true; cond; ) {
1468 jermar 238
        btree_node_t *node;
1594 jermar 239
 
240
        ASSERT(!list_empty(&as->as_area_btree.leaf_head));
2087 jermar 241
        node = list_get_instance(as->as_area_btree.leaf_head.next,
242
            btree_node_t, leaf_link);
1594 jermar 243
 
244
        if ((cond = node->keys)) {
245
            as_area_destroy(as, node->key[0]);
246
        }
1468 jermar 247
    }
1495 jermar 248
 
1483 jermar 249
    btree_destroy(&as->as_area_btree);
2089 decky 250
#ifdef AS_PAGE_TABLE
2106 jermar 251
    page_table_destroy(as->genarch.page_table);
2089 decky 252
#else
253
    page_table_destroy(NULL);
254
#endif
1468 jermar 255
 
256
    interrupts_restore(ipl);
2126 decky 257
 
1890 jermar 258
    slab_free(as_slab, as);
973 palkovsky 259
}
260
 
703 jermar 261
/** Create address space area of common attributes.
262
 *
263
 * The created address space area is added to the target address space.
264
 *
3425 svoboda 265
 * @param as        Target address space.
266
 * @param flags     Flags of the area memory.
267
 * @param size      Size of area.
268
 * @param base      Base address of area.
269
 * @param attrs     Attributes of the area.
270
 * @param backend   Address space area backend. NULL if no backend is used.
271
 * @param backend_data  NULL or a pointer to an array holding two void *.
703 jermar 272
 *
3425 svoboda 273
 * @return      Address space area on success or NULL on failure.
703 jermar 274
 */
2069 jermar 275
as_area_t *
276
as_area_create(as_t *as, int flags, size_t size, uintptr_t base, int attrs,
3425 svoboda 277
    mem_backend_t *backend, mem_backend_data_t *backend_data)
703 jermar 278
{
279
    ipl_t ipl;
280
    as_area_t *a;
281
 
282
    if (base % PAGE_SIZE)
1048 jermar 283
        return NULL;
284
 
1233 jermar 285
    if (!size)
286
        return NULL;
287
 
1048 jermar 288
    /* Writeable executable areas are not supported. */
289
    if ((flags & AS_AREA_EXEC) && (flags & AS_AREA_WRITE))
290
        return NULL;
703 jermar 291
 
292
    ipl = interrupts_disable();
1380 jermar 293
    mutex_lock(&as->lock);
703 jermar 294
 
1048 jermar 295
    if (!check_area_conflicts(as, base, size, NULL)) {
1380 jermar 296
        mutex_unlock(&as->lock);
1048 jermar 297
        interrupts_restore(ipl);
298
        return NULL;
299
    }
703 jermar 300
 
822 palkovsky 301
    a = (as_area_t *) malloc(sizeof(as_area_t), 0);
703 jermar 302
 
3425 svoboda 303
    mutex_initialize(&a->lock, MUTEX_PASSIVE);
822 palkovsky 304
 
1424 jermar 305
    a->as = as;
1026 jermar 306
    a->flags = flags;
1239 jermar 307
    a->attributes = attrs;
1048 jermar 308
    a->pages = SIZE2FRAMES(size);
822 palkovsky 309
    a->base = base;
1409 jermar 310
    a->sh_info = NULL;
311
    a->backend = backend;
1424 jermar 312
    if (backend_data)
313
        a->backend_data = *backend_data;
314
    else
3424 svoboda 315
        memsetb(&a->backend_data, sizeof(a->backend_data), 0);
1424 jermar 316
 
1387 jermar 317
    btree_create(&a->used_space);
822 palkovsky 318
 
1147 jermar 319
    btree_insert(&as->as_area_btree, base, (void *) a, NULL);
822 palkovsky 320
 
1380 jermar 321
    mutex_unlock(&as->lock);
703 jermar 322
    interrupts_restore(ipl);
704 jermar 323
 
703 jermar 324
    return a;
325
}
326
 
1235 jermar 327
/** Find address space area and change it.
328
 *
3425 svoboda 329
 * @param as        Address space.
330
 * @param address   Virtual address belonging to the area to be changed.
331
 *          Must be page-aligned.
332
 * @param size      New size of the virtual memory block starting at
333
 *          address.
334
 * @param flags     Flags influencing the remap operation. Currently unused.
1235 jermar 335
 *
3425 svoboda 336
 * @return      Zero on success or a value from @ref errno.h otherwise.
1235 jermar 337
 */
1780 jermar 338
int as_area_resize(as_t *as, uintptr_t address, size_t size, int flags)
1235 jermar 339
{
1306 jermar 340
    as_area_t *area;
1235 jermar 341
    ipl_t ipl;
342
    size_t pages;
343
 
344
    ipl = interrupts_disable();
1380 jermar 345
    mutex_lock(&as->lock);
1235 jermar 346
 
347
    /*
348
     * Locate the area.
349
     */
350
    area = find_area_and_lock(as, address);
351
    if (!area) {
1380 jermar 352
        mutex_unlock(&as->lock);
1235 jermar 353
        interrupts_restore(ipl);
1306 jermar 354
        return ENOENT;
1235 jermar 355
    }
356
 
1424 jermar 357
    if (area->backend == &phys_backend) {
1235 jermar 358
        /*
359
         * Remapping of address space areas associated
360
         * with memory mapped devices is not supported.
361
         */
1380 jermar 362
        mutex_unlock(&area->lock);
363
        mutex_unlock(&as->lock);
1235 jermar 364
        interrupts_restore(ipl);
1306 jermar 365
        return ENOTSUP;
1235 jermar 366
    }
1409 jermar 367
    if (area->sh_info) {
368
        /*
369
         * Remapping of shared address space areas
370
         * is not supported.
371
         */
372
        mutex_unlock(&area->lock);
373
        mutex_unlock(&as->lock);
374
        interrupts_restore(ipl);
375
        return ENOTSUP;
376
    }
1235 jermar 377
 
378
    pages = SIZE2FRAMES((address - area->base) + size);
379
    if (!pages) {
380
        /*
381
         * Zero size address space areas are not allowed.
382
         */
1380 jermar 383
        mutex_unlock(&area->lock);
384
        mutex_unlock(&as->lock);
1235 jermar 385
        interrupts_restore(ipl);
1306 jermar 386
        return EPERM;
1235 jermar 387
    }
388
 
389
    if (pages < area->pages) {
1403 jermar 390
        bool cond;
3425 svoboda 391
        uintptr_t start_free = area->base + pages * PAGE_SIZE;
1235 jermar 392
 
393
        /*
394
         * Shrinking the area.
395
         * No need to check for overlaps.
396
         */
1403 jermar 397
 
398
        /*
1436 jermar 399
         * Start TLB shootdown sequence.
400
         */
3425 svoboda 401
        tlb_shootdown_start(TLB_INVL_PAGES, as->asid, area->base +
2087 jermar 402
            pages * PAGE_SIZE, area->pages - pages);
1436 jermar 403
 
404
        /*
1403 jermar 405
         * Remove frames belonging to used space starting from
406
         * the highest addresses downwards until an overlap with
407
         * the resized address space area is found. Note that this
408
         * is also the right way to remove part of the used_space
409
         * B+tree leaf list.
410
         */    
411
        for (cond = true; cond;) {
412
            btree_node_t *node;
413
 
414
            ASSERT(!list_empty(&area->used_space.leaf_head));
2087 jermar 415
            node =
416
                list_get_instance(area->used_space.leaf_head.prev,
417
                btree_node_t, leaf_link);
1403 jermar 418
            if ((cond = (bool) node->keys)) {
1780 jermar 419
                uintptr_t b = node->key[node->keys - 1];
2087 jermar 420
                count_t c =
421
                    (count_t) node->value[node->keys - 1];
2745 decky 422
                unsigned int i = 0;
1235 jermar 423
 
2087 jermar 424
                if (overlaps(b, c * PAGE_SIZE, area->base,
2133 jermar 425
                    pages * PAGE_SIZE)) {
1403 jermar 426
 
2087 jermar 427
                    if (b + c * PAGE_SIZE <= start_free) {
1403 jermar 428
                        /*
2087 jermar 429
                         * The whole interval fits
430
                         * completely in the resized
431
                         * address space area.
1403 jermar 432
                         */
433
                        break;
434
                    }
435
 
436
                    /*
2087 jermar 437
                     * Part of the interval corresponding
438
                     * to b and c overlaps with the resized
439
                     * address space area.
1403 jermar 440
                     */
441
 
442
                    cond = false;   /* we are almost done */
443
                    i = (start_free - b) >> PAGE_WIDTH;
3425 svoboda 444
                    if (!used_space_remove(area, start_free,
445
                        c - i))
4377 svoboda 446
                        panic("Cannot remove used "
447
                            "space.");
1403 jermar 448
                } else {
449
                    /*
2087 jermar 450
                     * The interval of used space can be
451
                     * completely removed.
1403 jermar 452
                     */
453
                    if (!used_space_remove(area, b, c))
4377 svoboda 454
                        panic("Cannot remove used "
455
                            "space.");
1403 jermar 456
                }
457
 
458
                for (; i < c; i++) {
459
                    pte_t *pte;
460
 
461
                    page_table_lock(as, false);
2087 jermar 462
                    pte = page_mapping_find(as, b +
463
                        i * PAGE_SIZE);
464
                    ASSERT(pte && PTE_VALID(pte) &&
465
                        PTE_PRESENT(pte));
466
                    if (area->backend &&
467
                        area->backend->frame_free) {
1424 jermar 468
                        area->backend->frame_free(area,
2087 jermar 469
                            b + i * PAGE_SIZE,
470
                            PTE_GET_FRAME(pte));
1409 jermar 471
                    }
2087 jermar 472
                    page_mapping_remove(as, b +
473
                        i * PAGE_SIZE);
1403 jermar 474
                    page_table_unlock(as, false);
475
                }
1235 jermar 476
            }
477
        }
1436 jermar 478
 
1235 jermar 479
        /*
1436 jermar 480
         * Finish TLB shootdown sequence.
1235 jermar 481
         */
2183 jermar 482
 
2087 jermar 483
        tlb_invalidate_pages(as->asid, area->base + pages * PAGE_SIZE,
484
            area->pages - pages);
1889 jermar 485
        /*
486
         * Invalidate software translation caches (e.g. TSB on sparc64).
487
         */
2087 jermar 488
        as_invalidate_translation_cache(as, area->base +
489
            pages * PAGE_SIZE, area->pages - pages);
2183 jermar 490
        tlb_shootdown_finalize();
491
 
1235 jermar 492
    } else {
493
        /*
494
         * Growing the area.
495
         * Check for overlaps with other address space areas.
496
         */
2087 jermar 497
        if (!check_area_conflicts(as, address, pages * PAGE_SIZE,
498
            area)) {
1380 jermar 499
            mutex_unlock(&area->lock);
500
            mutex_unlock(&as->lock);       
1235 jermar 501
            interrupts_restore(ipl);
1306 jermar 502
            return EADDRNOTAVAIL;
1235 jermar 503
        }
504
    }
505
 
506
    area->pages = pages;
507
 
1380 jermar 508
    mutex_unlock(&area->lock);
509
    mutex_unlock(&as->lock);
1235 jermar 510
    interrupts_restore(ipl);
511
 
1306 jermar 512
    return 0;
1235 jermar 513
}
514
 
1306 jermar 515
/** Destroy address space area.
516
 *
3425 svoboda 517
 * @param as        Address space.
518
 * @param address   Address within the area to be deleted.
1306 jermar 519
 *
3425 svoboda 520
 * @return      Zero on success or a value from @ref errno.h on failure.
1306 jermar 521
 */
1780 jermar 522
int as_area_destroy(as_t *as, uintptr_t address)
1306 jermar 523
{
524
    as_area_t *area;
1780 jermar 525
    uintptr_t base;
1495 jermar 526
    link_t *cur;
1306 jermar 527
    ipl_t ipl;
528
 
529
    ipl = interrupts_disable();
1380 jermar 530
    mutex_lock(&as->lock);
1306 jermar 531
 
532
    area = find_area_and_lock(as, address);
533
    if (!area) {
1380 jermar 534
        mutex_unlock(&as->lock);
1306 jermar 535
        interrupts_restore(ipl);
536
        return ENOENT;
537
    }
538
 
1403 jermar 539
    base = area->base;
540
 
1411 jermar 541
    /*
1436 jermar 542
     * Start TLB shootdown sequence.
543
     */
1889 jermar 544
    tlb_shootdown_start(TLB_INVL_PAGES, as->asid, area->base, area->pages);
1436 jermar 545
 
546
    /*
1411 jermar 547
     * Visit only the pages mapped by used_space B+tree.
548
     */
2087 jermar 549
    for (cur = area->used_space.leaf_head.next;
550
        cur != &area->used_space.leaf_head; cur = cur->next) {
1411 jermar 551
        btree_node_t *node;
2745 decky 552
        unsigned int i;
1403 jermar 553
 
1495 jermar 554
        node = list_get_instance(cur, btree_node_t, leaf_link);
555
        for (i = 0; i < node->keys; i++) {
1780 jermar 556
            uintptr_t b = node->key[i];
1495 jermar 557
            count_t j;
1411 jermar 558
            pte_t *pte;
1403 jermar 559
 
1495 jermar 560
            for (j = 0; j < (count_t) node->value[i]; j++) {
1411 jermar 561
                page_table_lock(as, false);
2087 jermar 562
                pte = page_mapping_find(as, b + j * PAGE_SIZE);
563
                ASSERT(pte && PTE_VALID(pte) &&
564
                    PTE_PRESENT(pte));
565
                if (area->backend &&
566
                    area->backend->frame_free) {
567
                    area->backend->frame_free(area, b +
2133 jermar 568
                        j * PAGE_SIZE, PTE_GET_FRAME(pte));
1403 jermar 569
                }
2087 jermar 570
                page_mapping_remove(as, b + j * PAGE_SIZE);            
1411 jermar 571
                page_table_unlock(as, false);
1306 jermar 572
            }
573
        }
574
    }
1403 jermar 575
 
1306 jermar 576
    /*
1436 jermar 577
     * Finish TLB shootdown sequence.
1306 jermar 578
     */
2183 jermar 579
 
1889 jermar 580
    tlb_invalidate_pages(as->asid, area->base, area->pages);
581
    /*
2087 jermar 582
     * Invalidate potential software translation caches (e.g. TSB on
583
     * sparc64).
1889 jermar 584
     */
585
    as_invalidate_translation_cache(as, area->base, area->pages);
2183 jermar 586
    tlb_shootdown_finalize();
1889 jermar 587
 
1436 jermar 588
    btree_destroy(&area->used_space);
1306 jermar 589
 
1309 jermar 590
    area->attributes |= AS_AREA_ATTR_PARTIAL;
1409 jermar 591
 
592
    if (area->sh_info)
593
        sh_info_remove_reference(area->sh_info);
594
 
1380 jermar 595
    mutex_unlock(&area->lock);
1306 jermar 596
 
597
    /*
598
     * Remove the empty area from address space.
599
     */
1889 jermar 600
    btree_remove(&as->as_area_btree, base, NULL);
1306 jermar 601
 
1309 jermar 602
    free(area);
603
 
1889 jermar 604
    mutex_unlock(&as->lock);
1306 jermar 605
    interrupts_restore(ipl);
606
    return 0;
607
}
608
 
1413 jermar 609
/** Share address space area with another or the same address space.
1235 jermar 610
 *
1424 jermar 611
 * Address space area mapping is shared with a new address space area.
612
 * If the source address space area has not been shared so far,
613
 * a new sh_info is created. The new address space area simply gets the
614
 * sh_info of the source area. The process of duplicating the
615
 * mapping is done through the backend share function.
1413 jermar 616
 *
3425 svoboda 617
 * @param src_as    Pointer to source address space.
618
 * @param src_base  Base address of the source address space area.
619
 * @param acc_size  Expected size of the source area.
620
 * @param dst_as    Pointer to destination address space.
621
 * @param dst_base  Target base address.
1417 jermar 622
 * @param dst_flags_mask Destination address space area flags mask.
1235 jermar 623
 *
3425 svoboda 624
 * @return      Zero on success or ENOENT if there is no such task or if
625
 *          there is no such address space area, EPERM if there was
626
 *          a problem in accepting the area or ENOMEM if there was a
627
 *          problem in allocating destination address space area.
628
 *          ENOTSUP is returned if the address space area backend
629
 *          does not support sharing.
1235 jermar 630
 */
1780 jermar 631
int as_area_share(as_t *src_as, uintptr_t src_base, size_t acc_size,
2647 jermar 632
    as_t *dst_as, uintptr_t dst_base, int dst_flags_mask)
1235 jermar 633
{
634
    ipl_t ipl;
1239 jermar 635
    int src_flags;
636
    size_t src_size;
637
    as_area_t *src_area, *dst_area;
1413 jermar 638
    share_info_t *sh_info;
1424 jermar 639
    mem_backend_t *src_backend;
640
    mem_backend_data_t src_backend_data;
1434 palkovsky 641
 
1235 jermar 642
    ipl = interrupts_disable();
1380 jermar 643
    mutex_lock(&src_as->lock);
1329 palkovsky 644
    src_area = find_area_and_lock(src_as, src_base);
1239 jermar 645
    if (!src_area) {
1238 jermar 646
        /*
647
         * Could not find the source address space area.
648
         */
1380 jermar 649
        mutex_unlock(&src_as->lock);
1238 jermar 650
        interrupts_restore(ipl);
651
        return ENOENT;
652
    }
2007 jermar 653
 
1424 jermar 654
    if (!src_area->backend || !src_area->backend->share) {
1413 jermar 655
        /*
1851 jermar 656
         * There is no backend or the backend does not
1424 jermar 657
         * know how to share the area.
1413 jermar 658
         */
659
        mutex_unlock(&src_area->lock);
660
        mutex_unlock(&src_as->lock);
661
        interrupts_restore(ipl);
662
        return ENOTSUP;
663
    }
664
 
1239 jermar 665
    src_size = src_area->pages * PAGE_SIZE;
666
    src_flags = src_area->flags;
1424 jermar 667
    src_backend = src_area->backend;
668
    src_backend_data = src_area->backend_data;
1544 palkovsky 669
 
670
    /* Share the cacheable flag from the original mapping */
671
    if (src_flags & AS_AREA_CACHEABLE)
672
        dst_flags_mask |= AS_AREA_CACHEABLE;
673
 
2087 jermar 674
    if (src_size != acc_size ||
675
        (src_flags & dst_flags_mask) != dst_flags_mask) {
1413 jermar 676
        mutex_unlock(&src_area->lock);
677
        mutex_unlock(&src_as->lock);
1235 jermar 678
        interrupts_restore(ipl);
679
        return EPERM;
680
    }
1413 jermar 681
 
1235 jermar 682
    /*
1413 jermar 683
     * Now we are committed to sharing the area.
1954 jermar 684
     * First, prepare the area for sharing.
1413 jermar 685
     * Then it will be safe to unlock it.
686
     */
687
    sh_info = src_area->sh_info;
688
    if (!sh_info) {
689
        sh_info = (share_info_t *) malloc(sizeof(share_info_t), 0);
3425 svoboda 690
        mutex_initialize(&sh_info->lock, MUTEX_PASSIVE);
1413 jermar 691
        sh_info->refcount = 2;
692
        btree_create(&sh_info->pagemap);
693
        src_area->sh_info = sh_info;
2647 jermar 694
        /*
695
         * Call the backend to setup sharing.
696
         */
697
        src_area->backend->share(src_area);
1413 jermar 698
    } else {
699
        mutex_lock(&sh_info->lock);
700
        sh_info->refcount++;
701
        mutex_unlock(&sh_info->lock);
702
    }
703
 
704
    mutex_unlock(&src_area->lock);
705
    mutex_unlock(&src_as->lock);
706
 
707
    /*
1239 jermar 708
     * Create copy of the source address space area.
709
     * The destination area is created with AS_AREA_ATTR_PARTIAL
710
     * attribute set which prevents race condition with
711
     * preliminary as_page_fault() calls.
1417 jermar 712
     * The flags of the source area are masked against dst_flags_mask
713
     * to support sharing in less privileged mode.
1235 jermar 714
     */
1461 palkovsky 715
    dst_area = as_area_create(dst_as, dst_flags_mask, src_size, dst_base,
2087 jermar 716
        AS_AREA_ATTR_PARTIAL, src_backend, &src_backend_data);
1239 jermar 717
    if (!dst_area) {
1235 jermar 718
        /*
719
         * Destination address space area could not be created.
720
         */
1413 jermar 721
        sh_info_remove_reference(sh_info);
722
 
1235 jermar 723
        interrupts_restore(ipl);
724
        return ENOMEM;
725
    }
2009 jermar 726
 
1235 jermar 727
    /*
1239 jermar 728
     * Now the destination address space area has been
729
     * fully initialized. Clear the AS_AREA_ATTR_PARTIAL
1413 jermar 730
     * attribute and set the sh_info.
1239 jermar 731
     */
2009 jermar 732
    mutex_lock(&dst_as->lock); 
1380 jermar 733
    mutex_lock(&dst_area->lock);
1239 jermar 734
    dst_area->attributes &= ~AS_AREA_ATTR_PARTIAL;
1413 jermar 735
    dst_area->sh_info = sh_info;
1380 jermar 736
    mutex_unlock(&dst_area->lock);
2009 jermar 737
    mutex_unlock(&dst_as->lock);   
738
 
1235 jermar 739
    interrupts_restore(ipl);
740
 
741
    return 0;
742
}
743
 
1423 jermar 744
/** Check access mode for address space area.
745
 *
746
 * The address space area must be locked prior to this call.
747
 *
3425 svoboda 748
 * @param area      Address space area.
749
 * @param access    Access mode.
1423 jermar 750
 *
3425 svoboda 751
 * @return      False if access violates area's permissions, true
752
 *          otherwise.
1423 jermar 753
 */
754
bool as_area_check_access(as_area_t *area, pf_access_t access)
755
{
756
    int flagmap[] = {
757
        [PF_ACCESS_READ] = AS_AREA_READ,
758
        [PF_ACCESS_WRITE] = AS_AREA_WRITE,
759
        [PF_ACCESS_EXEC] = AS_AREA_EXEC
760
    };
761
 
762
    if (!(area->flags & flagmap[access]))
763
        return false;
764
 
765
    return true;
766
}
767
 
3425 svoboda 768
/** Change adress space area flags.
769
 *
770
 * The idea is to have the same data, but with a different access mode.
771
 * This is needed e.g. for writing code into memory and then executing it.
772
 * In order for this to work properly, this may copy the data
773
 * into private anonymous memory (unless it's already there).
774
 *
4377 svoboda 775
 * @param as      Address space.
776
 * @param flags   Flags of the area memory.
777
 * @param address Address within the area to be changed.
3425 svoboda 778
 *
4377 svoboda 779
 * @return Zero on success or a value from @ref errno.h on failure.
780
 *
3425 svoboda 781
 */
782
int as_area_change_flags(as_t *as, int flags, uintptr_t address)
783
{
784
    as_area_t *area;
785
    uintptr_t base;
786
    link_t *cur;
787
    ipl_t ipl;
788
    int page_flags;
789
    uintptr_t *old_frame;
790
    index_t frame_idx;
791
    count_t used_pages;
4377 svoboda 792
 
3425 svoboda 793
    /* Flags for the new memory mapping */
794
    page_flags = area_flags_to_page_flags(flags);
795
 
796
    ipl = interrupts_disable();
797
    mutex_lock(&as->lock);
798
 
799
    area = find_area_and_lock(as, address);
800
    if (!area) {
801
        mutex_unlock(&as->lock);
802
        interrupts_restore(ipl);
803
        return ENOENT;
804
    }
805
 
4377 svoboda 806
    if ((area->sh_info) || (area->backend != &anon_backend)) {
3425 svoboda 807
        /* Copying shared areas not supported yet */
808
        /* Copying non-anonymous memory not supported yet */
809
        mutex_unlock(&area->lock);
810
        mutex_unlock(&as->lock);
811
        interrupts_restore(ipl);
812
        return ENOTSUP;
813
    }
814
 
815
    base = area->base;
816
 
817
    /*
818
     * Compute total number of used pages in the used_space B+tree
819
     */
820
    used_pages = 0;
821
 
822
    for (cur = area->used_space.leaf_head.next;
823
        cur != &area->used_space.leaf_head; cur = cur->next) {
824
        btree_node_t *node;
825
        unsigned int i;
826
 
827
        node = list_get_instance(cur, btree_node_t, leaf_link);
828
        for (i = 0; i < node->keys; i++) {
829
            used_pages += (count_t) node->value[i];
830
        }
831
    }
832
 
833
    /* An array for storing frame numbers */
834
    old_frame = malloc(used_pages * sizeof(uintptr_t), 0);
835
 
836
    /*
837
     * Start TLB shootdown sequence.
838
     */
839
    tlb_shootdown_start(TLB_INVL_PAGES, as->asid, area->base, area->pages);
840
 
841
    /*
842
     * Remove used pages from page tables and remember their frame
843
     * numbers.
844
     */
845
    frame_idx = 0;
846
 
847
    for (cur = area->used_space.leaf_head.next;
848
        cur != &area->used_space.leaf_head; cur = cur->next) {
849
        btree_node_t *node;
850
        unsigned int i;
851
 
852
        node = list_get_instance(cur, btree_node_t, leaf_link);
853
        for (i = 0; i < node->keys; i++) {
854
            uintptr_t b = node->key[i];
855
            count_t j;
856
            pte_t *pte;
857
 
858
            for (j = 0; j < (count_t) node->value[i]; j++) {
859
                page_table_lock(as, false);
860
                pte = page_mapping_find(as, b + j * PAGE_SIZE);
861
                ASSERT(pte && PTE_VALID(pte) &&
862
                    PTE_PRESENT(pte));
863
                old_frame[frame_idx++] = PTE_GET_FRAME(pte);
864
 
865
                /* Remove old mapping */
866
                page_mapping_remove(as, b + j * PAGE_SIZE);
867
                page_table_unlock(as, false);
868
            }
869
        }
870
    }
871
 
872
    /*
873
     * Finish TLB shootdown sequence.
874
     */
875
 
876
    tlb_invalidate_pages(as->asid, area->base, area->pages);
4377 svoboda 877
 
3425 svoboda 878
    /*
879
     * Invalidate potential software translation caches (e.g. TSB on
880
     * sparc64).
881
     */
882
    as_invalidate_translation_cache(as, area->base, area->pages);
883
    tlb_shootdown_finalize();
884
 
885
    /*
886
     * Set the new flags.
887
     */
888
    area->flags = flags;
889
 
890
    /*
891
     * Map pages back in with new flags. This step is kept separate
892
     * so that the memory area could not be accesed with both the old and
893
     * the new flags at once.
894
     */
895
    frame_idx = 0;
896
 
897
    for (cur = area->used_space.leaf_head.next;
898
        cur != &area->used_space.leaf_head; cur = cur->next) {
899
        btree_node_t *node;
900
        unsigned int i;
901
 
902
        node = list_get_instance(cur, btree_node_t, leaf_link);
903
        for (i = 0; i < node->keys; i++) {
904
            uintptr_t b = node->key[i];
905
            count_t j;
906
 
907
            for (j = 0; j < (count_t) node->value[i]; j++) {
908
                page_table_lock(as, false);
909
 
910
                /* Insert the new mapping */
911
                page_mapping_insert(as, b + j * PAGE_SIZE,
912
                    old_frame[frame_idx++], page_flags);
913
 
914
                page_table_unlock(as, false);
915
            }
916
        }
917
    }
918
 
919
    free(old_frame);
920
 
921
    mutex_unlock(&area->lock);
922
    mutex_unlock(&as->lock);
923
    interrupts_restore(ipl);
924
 
925
    return 0;
926
}
927
 
928
 
703 jermar 929
/** Handle page fault within the current address space.
930
 *
3425 svoboda 931
 * This is the high-level page fault handler. It decides whether the page fault
932
 * can be resolved by any backend and if so, it invokes the backend to resolve
933
 * the page fault.
1409 jermar 934
 *
703 jermar 935
 * Interrupts are assumed disabled.
936
 *
3425 svoboda 937
 * @param page      Faulting page.
938
 * @param access    Access mode that caused the page fault (i.e.
939
 *          read/write/exec).
940
 * @param istate    Pointer to the interrupted state.
703 jermar 941
 *
3425 svoboda 942
 * @return      AS_PF_FAULT on page fault, AS_PF_OK on success or
943
 *          AS_PF_DEFER if the fault was caused by copy_to_uspace()
944
 *          or copy_from_uspace().
703 jermar 945
 */
1780 jermar 946
int as_page_fault(uintptr_t page, pf_access_t access, istate_t *istate)
703 jermar 947
{
1044 jermar 948
    pte_t *pte;
977 jermar 949
    as_area_t *area;
703 jermar 950
 
1380 jermar 951
    if (!THREAD)
1409 jermar 952
        return AS_PF_FAULT;
1380 jermar 953
 
703 jermar 954
    ASSERT(AS);
1044 jermar 955
 
1380 jermar 956
    mutex_lock(&AS->lock);
977 jermar 957
    area = find_area_and_lock(AS, page);   
703 jermar 958
    if (!area) {
959
        /*
960
         * No area contained mapping for 'page'.
961
         * Signal page fault to low-level handler.
962
         */
1380 jermar 963
        mutex_unlock(&AS->lock);
1288 jermar 964
        goto page_fault;
703 jermar 965
    }
966
 
1239 jermar 967
    if (area->attributes & AS_AREA_ATTR_PARTIAL) {
968
        /*
969
         * The address space area is not fully initialized.
970
         * Avoid possible race by returning error.
971
         */
1380 jermar 972
        mutex_unlock(&area->lock);
973
        mutex_unlock(&AS->lock);
1288 jermar 974
        goto page_fault;       
1239 jermar 975
    }
976
 
1424 jermar 977
    if (!area->backend || !area->backend->page_fault) {
1409 jermar 978
        /*
979
         * The address space area is not backed by any backend
980
         * or the backend cannot handle page faults.
981
         */
982
        mutex_unlock(&area->lock);
983
        mutex_unlock(&AS->lock);
984
        goto page_fault;       
985
    }
1179 jermar 986
 
1044 jermar 987
    page_table_lock(AS, false);
988
 
703 jermar 989
    /*
3425 svoboda 990
     * To avoid race condition between two page faults on the same address,
991
     * we need to make sure the mapping has not been already inserted.
1044 jermar 992
     */
993
    if ((pte = page_mapping_find(AS, page))) {
994
        if (PTE_PRESENT(pte)) {
1423 jermar 995
            if (((access == PF_ACCESS_READ) && PTE_READABLE(pte)) ||
2087 jermar 996
                (access == PF_ACCESS_WRITE && PTE_WRITABLE(pte)) ||
997
                (access == PF_ACCESS_EXEC && PTE_EXECUTABLE(pte))) {
1423 jermar 998
                page_table_unlock(AS, false);
999
                mutex_unlock(&area->lock);
1000
                mutex_unlock(&AS->lock);
1001
                return AS_PF_OK;
1002
            }
1044 jermar 1003
        }
1004
    }
1409 jermar 1005
 
1044 jermar 1006
    /*
1409 jermar 1007
     * Resort to the backend page fault handler.
703 jermar 1008
     */
1424 jermar 1009
    if (area->backend->page_fault(area, page, access) != AS_PF_OK) {
1409 jermar 1010
        page_table_unlock(AS, false);
1011
        mutex_unlock(&area->lock);
1012
        mutex_unlock(&AS->lock);
1013
        goto page_fault;
1014
    }
703 jermar 1015
 
1044 jermar 1016
    page_table_unlock(AS, false);
1380 jermar 1017
    mutex_unlock(&area->lock);
1018
    mutex_unlock(&AS->lock);
1288 jermar 1019
    return AS_PF_OK;
1020
 
1021
page_fault:
1022
    if (THREAD->in_copy_from_uspace) {
1023
        THREAD->in_copy_from_uspace = false;
2087 jermar 1024
        istate_set_retaddr(istate,
1025
            (uintptr_t) &memcpy_from_uspace_failover_address);
1288 jermar 1026
    } else if (THREAD->in_copy_to_uspace) {
1027
        THREAD->in_copy_to_uspace = false;
2087 jermar 1028
        istate_set_retaddr(istate,
1029
            (uintptr_t) &memcpy_to_uspace_failover_address);
1288 jermar 1030
    } else {
1031
        return AS_PF_FAULT;
1032
    }
1033
 
1034
    return AS_PF_DEFER;
703 jermar 1035
}
1036
 
823 jermar 1037
/** Switch address spaces.
703 jermar 1038
 *
1380 jermar 1039
 * Note that this function cannot sleep as it is essentially a part of
2170 jermar 1040
 * scheduling. Sleeping here would lead to deadlock on wakeup. Another
1041
 * thing which is forbidden in this context is locking the address space.
1380 jermar 1042
 *
2183 jermar 1043
 * When this function is enetered, no spinlocks may be held.
1044
 *
3425 svoboda 1045
 * @param old       Old address space or NULL.
1046
 * @param new       New address space.
703 jermar 1047
 */
2106 jermar 1048
void as_switch(as_t *old_as, as_t *new_as)
703 jermar 1049
{
2183 jermar 1050
    DEADLOCK_PROBE_INIT(p_asidlock);
1051
    preemption_disable();
1052
retry:
1053
    (void) interrupts_disable();
1054
    if (!spinlock_trylock(&asidlock)) {
1055
        /*
1056
         * Avoid deadlock with TLB shootdown.
1057
         * We can enable interrupts here because
1058
         * preemption is disabled. We should not be
1059
         * holding any other lock.
1060
         */
1061
        (void) interrupts_enable();
1062
        DEADLOCK_PROBE(p_asidlock, DEADLOCK_THRESHOLD);
1063
        goto retry;
1064
    }
1065
    preemption_enable();
703 jermar 1066
 
1067
    /*
823 jermar 1068
     * First, take care of the old address space.
1069
     */
2106 jermar 1070
    if (old_as) {
1071
        ASSERT(old_as->cpu_refcount);
1072
        if((--old_as->cpu_refcount == 0) && (old_as != AS_KERNEL)) {
823 jermar 1073
            /*
1074
             * The old address space is no longer active on
1075
             * any processor. It can be appended to the
1076
             * list of inactive address spaces with assigned
1077
             * ASID.
1078
             */
2141 jermar 1079
            ASSERT(old_as->asid != ASID_INVALID);
1080
            list_append(&old_as->inactive_as_with_asid_link,
1081
                &inactive_as_with_asid_head);
823 jermar 1082
        }
1890 jermar 1083
 
1084
        /*
1085
         * Perform architecture-specific tasks when the address space
1086
         * is being removed from the CPU.
1087
         */
2106 jermar 1088
        as_deinstall_arch(old_as);
823 jermar 1089
    }
1090
 
1091
    /*
1092
     * Second, prepare the new address space.
1093
     */
2106 jermar 1094
    if ((new_as->cpu_refcount++ == 0) && (new_as != AS_KERNEL)) {
2170 jermar 1095
        if (new_as->asid != ASID_INVALID)
2106 jermar 1096
            list_remove(&new_as->inactive_as_with_asid_link);
2170 jermar 1097
        else
1098
            new_as->asid = asid_get();
823 jermar 1099
    }
2106 jermar 1100
#ifdef AS_PAGE_TABLE
1101
    SET_PTL0_ADDRESS(new_as->genarch.page_table);
1102
#endif
823 jermar 1103
 
1104
    /*
703 jermar 1105
     * Perform architecture-specific steps.
727 jermar 1106
     * (e.g. write ASID to hardware register etc.)
703 jermar 1107
     */
2106 jermar 1108
    as_install_arch(new_as);
2170 jermar 1109
 
1110
    spinlock_unlock(&asidlock);
703 jermar 1111
 
2106 jermar 1112
    AS = new_as;
703 jermar 1113
}
754 jermar 1114
 
1235 jermar 1115
/** Convert address space area flags to page flags.
754 jermar 1116
 *
3425 svoboda 1117
 * @param aflags    Flags of some address space area.
754 jermar 1118
 *
3425 svoboda 1119
 * @return      Flags to be passed to page_mapping_insert().
754 jermar 1120
 */
1235 jermar 1121
int area_flags_to_page_flags(int aflags)
754 jermar 1122
{
1123
    int flags;
1124
 
1178 jermar 1125
    flags = PAGE_USER | PAGE_PRESENT;
754 jermar 1126
 
1235 jermar 1127
    if (aflags & AS_AREA_READ)
1026 jermar 1128
        flags |= PAGE_READ;
1129
 
1235 jermar 1130
    if (aflags & AS_AREA_WRITE)
1026 jermar 1131
        flags |= PAGE_WRITE;
1132
 
1235 jermar 1133
    if (aflags & AS_AREA_EXEC)
1026 jermar 1134
        flags |= PAGE_EXEC;
1135
 
1424 jermar 1136
    if (aflags & AS_AREA_CACHEABLE)
1178 jermar 1137
        flags |= PAGE_CACHEABLE;
1138
 
754 jermar 1139
    return flags;
1140
}
756 jermar 1141
 
1235 jermar 1142
/** Compute flags for virtual address translation subsytem.
1143
 *
1144
 * The address space area must be locked.
1145
 * Interrupts must be disabled.
1146
 *
3425 svoboda 1147
 * @param a     Address space area.
1235 jermar 1148
 *
3425 svoboda 1149
 * @return      Flags to be used in page_mapping_insert().
1235 jermar 1150
 */
1409 jermar 1151
int as_area_get_flags(as_area_t *a)
1235 jermar 1152
{
1153
    return area_flags_to_page_flags(a->flags);
1154
}
1155
 
756 jermar 1156
/** Create page table.
1157
 *
3425 svoboda 1158
 * Depending on architecture, create either address space private or global page
1159
 * table.
756 jermar 1160
 *
3425 svoboda 1161
 * @param flags     Flags saying whether the page table is for the kernel
1162
 *          address space.
756 jermar 1163
 *
3425 svoboda 1164
 * @return      First entry of the page table.
756 jermar 1165
 */
1166
pte_t *page_table_create(int flags)
1167
{
2125 decky 1168
    ASSERT(as_operations);
1169
    ASSERT(as_operations->page_table_create);
1170
 
1171
    return as_operations->page_table_create(flags);
756 jermar 1172
}
977 jermar 1173
 
1468 jermar 1174
/** Destroy page table.
1175
 *
1176
 * Destroy page table in architecture specific way.
1177
 *
3425 svoboda 1178
 * @param page_table    Physical address of PTL0.
1468 jermar 1179
 */
1180
void page_table_destroy(pte_t *page_table)
1181
{
2125 decky 1182
    ASSERT(as_operations);
1183
    ASSERT(as_operations->page_table_destroy);
1184
 
1185
    as_operations->page_table_destroy(page_table);
1468 jermar 1186
}
1187
 
1044 jermar 1188
/** Lock page table.
1189
 *
1190
 * This function should be called before any page_mapping_insert(),
1191
 * page_mapping_remove() and page_mapping_find().
1192
 *
1193
 * Locking order is such that address space areas must be locked
1194
 * prior to this call. Address space can be locked prior to this
1195
 * call in which case the lock argument is false.
1196
 *
3425 svoboda 1197
 * @param as        Address space.
1198
 * @param lock      If false, do not attempt to lock as->lock.
1044 jermar 1199
 */
1200
void page_table_lock(as_t *as, bool lock)
1201
{
1202
    ASSERT(as_operations);
1203
    ASSERT(as_operations->page_table_lock);
2125 decky 1204
 
1044 jermar 1205
    as_operations->page_table_lock(as, lock);
1206
}
1207
 
1208
/** Unlock page table.
1209
 *
3425 svoboda 1210
 * @param as        Address space.
1211
 * @param unlock    If false, do not attempt to unlock as->lock.
1044 jermar 1212
 */
1213
void page_table_unlock(as_t *as, bool unlock)
1214
{
1215
    ASSERT(as_operations);
1216
    ASSERT(as_operations->page_table_unlock);
2125 decky 1217
 
1044 jermar 1218
    as_operations->page_table_unlock(as, unlock);
1219
}
1220
 
977 jermar 1221
 
1222
/** Find address space area and lock it.
1223
 *
1224
 * The address space must be locked and interrupts must be disabled.
1225
 *
3425 svoboda 1226
 * @param as        Address space.
1227
 * @param va        Virtual address.
977 jermar 1228
 *
3425 svoboda 1229
 * @return      Locked address space area containing va on success or
1230
 *          NULL on failure.
977 jermar 1231
 */
1780 jermar 1232
as_area_t *find_area_and_lock(as_t *as, uintptr_t va)
977 jermar 1233
{
1234
    as_area_t *a;
1147 jermar 1235
    btree_node_t *leaf, *lnode;
2745 decky 1236
    unsigned int i;
977 jermar 1237
 
1147 jermar 1238
    a = (as_area_t *) btree_search(&as->as_area_btree, va, &leaf);
1239
    if (a) {
1240
        /* va is the base address of an address space area */
1380 jermar 1241
        mutex_lock(&a->lock);
1147 jermar 1242
        return a;
1243
    }
1244
 
1245
    /*
1150 jermar 1246
     * Search the leaf node and the righmost record of its left neighbour
1147 jermar 1247
     * to find out whether this is a miss or va belongs to an address
1248
     * space area found there.
1249
     */
1250
 
1251
    /* First, search the leaf node itself. */
1252
    for (i = 0; i < leaf->keys; i++) {
1253
        a = (as_area_t *) leaf->value[i];
1380 jermar 1254
        mutex_lock(&a->lock);
1147 jermar 1255
        if ((a->base <= va) && (va < a->base + a->pages * PAGE_SIZE)) {
1256
            return a;
1257
        }
1380 jermar 1258
        mutex_unlock(&a->lock);
1147 jermar 1259
    }
977 jermar 1260
 
1147 jermar 1261
    /*
1150 jermar 1262
     * Second, locate the left neighbour and test its last record.
1148 jermar 1263
     * Because of its position in the B+tree, it must have base < va.
1147 jermar 1264
     */
2087 jermar 1265
    lnode = btree_leaf_node_left_neighbour(&as->as_area_btree, leaf);
1266
    if (lnode) {
1147 jermar 1267
        a = (as_area_t *) lnode->value[lnode->keys - 1];
1380 jermar 1268
        mutex_lock(&a->lock);
1147 jermar 1269
        if (va < a->base + a->pages * PAGE_SIZE) {
1048 jermar 1270
            return a;
1147 jermar 1271
        }
1380 jermar 1272
        mutex_unlock(&a->lock);
977 jermar 1273
    }
1274
 
1275
    return NULL;
1276
}
1048 jermar 1277
 
1278
/** Check area conflicts with other areas.
1279
 *
1280
 * The address space must be locked and interrupts must be disabled.
1281
 *
3425 svoboda 1282
 * @param as        Address space.
1283
 * @param va        Starting virtual address of the area being tested.
1284
 * @param size      Size of the area being tested.
1285
 * @param avoid_area    Do not touch this area.
1048 jermar 1286
 *
3425 svoboda 1287
 * @return      True if there is no conflict, false otherwise.
1048 jermar 1288
 */
3425 svoboda 1289
bool
1290
check_area_conflicts(as_t *as, uintptr_t va, size_t size, as_area_t *avoid_area)
1048 jermar 1291
{
1292
    as_area_t *a;
1147 jermar 1293
    btree_node_t *leaf, *node;
2745 decky 1294
    unsigned int i;
1048 jermar 1295
 
1070 jermar 1296
    /*
1297
     * We don't want any area to have conflicts with NULL page.
1298
     */
1299
    if (overlaps(va, size, NULL, PAGE_SIZE))
1300
        return false;
1301
 
1147 jermar 1302
    /*
1303
     * The leaf node is found in O(log n), where n is proportional to
1304
     * the number of address space areas belonging to as.
1305
     * The check for conflicts is then attempted on the rightmost
1150 jermar 1306
     * record in the left neighbour, the leftmost record in the right
1307
     * neighbour and all records in the leaf node itself.
1147 jermar 1308
     */
1048 jermar 1309
 
1147 jermar 1310
    if ((a = (as_area_t *) btree_search(&as->as_area_btree, va, &leaf))) {
1311
        if (a != avoid_area)
1312
            return false;
1313
    }
1314
 
1315
    /* First, check the two border cases. */
1150 jermar 1316
    if ((node = btree_leaf_node_left_neighbour(&as->as_area_btree, leaf))) {
1147 jermar 1317
        a = (as_area_t *) node->value[node->keys - 1];
1380 jermar 1318
        mutex_lock(&a->lock);
1147 jermar 1319
        if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
1380 jermar 1320
            mutex_unlock(&a->lock);
1147 jermar 1321
            return false;
1322
        }
1380 jermar 1323
        mutex_unlock(&a->lock);
1147 jermar 1324
    }
2087 jermar 1325
    node = btree_leaf_node_right_neighbour(&as->as_area_btree, leaf);
1326
    if (node) {
1147 jermar 1327
        a = (as_area_t *) node->value[0];
1380 jermar 1328
        mutex_lock(&a->lock);
1147 jermar 1329
        if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
1380 jermar 1330
            mutex_unlock(&a->lock);
1147 jermar 1331
            return false;
1332
        }
1380 jermar 1333
        mutex_unlock(&a->lock);
1147 jermar 1334
    }
1335
 
1336
    /* Second, check the leaf node. */
1337
    for (i = 0; i < leaf->keys; i++) {
1338
        a = (as_area_t *) leaf->value[i];
1339
 
1048 jermar 1340
        if (a == avoid_area)
1341
            continue;
1147 jermar 1342
 
1380 jermar 1343
        mutex_lock(&a->lock);
1147 jermar 1344
        if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
1380 jermar 1345
            mutex_unlock(&a->lock);
1147 jermar 1346
            return false;
1347
        }
1380 jermar 1348
        mutex_unlock(&a->lock);
1048 jermar 1349
    }
1350
 
1070 jermar 1351
    /*
1352
     * So far, the area does not conflict with other areas.
1353
     * Check if it doesn't conflict with kernel address space.
1354
     */  
1355
    if (!KERNEL_ADDRESS_SPACE_SHADOWED) {
1356
        return !overlaps(va, size,
2087 jermar 1357
            KERNEL_ADDRESS_SPACE_START,
1358
            KERNEL_ADDRESS_SPACE_END - KERNEL_ADDRESS_SPACE_START);
1070 jermar 1359
    }
1360
 
1048 jermar 1361
    return true;
1362
}
1235 jermar 1363
 
2556 jermar 1364
/** Return size of the address space area with given base.
1365
 *
1366
 * @param base      Arbitrary address insede the address space area.
1367
 *
1368
 * @return      Size of the address space area in bytes or zero if it
1369
 *          does not exist.
1370
 */
1371
size_t as_area_get_size(uintptr_t base)
1329 palkovsky 1372
{
1373
    ipl_t ipl;
1374
    as_area_t *src_area;
1375
    size_t size;
1376
 
1377
    ipl = interrupts_disable();
1378
    src_area = find_area_and_lock(AS, base);
3425 svoboda 1379
    if (src_area) {
1329 palkovsky 1380
        size = src_area->pages * PAGE_SIZE;
1380 jermar 1381
        mutex_unlock(&src_area->lock);
1329 palkovsky 1382
    } else {
1383
        size = 0;
1384
    }
1385
    interrupts_restore(ipl);
1386
    return size;
1387
}
1388
 
1387 jermar 1389
/** Mark portion of address space area as used.
1390
 *
1391
 * The address space area must be already locked.
1392
 *
3425 svoboda 1393
 * @param a     Address space area.
1394
 * @param page      First page to be marked.
1395
 * @param count     Number of page to be marked.
1387 jermar 1396
 *
3425 svoboda 1397
 * @return      Zero on failure and non-zero on success.
1387 jermar 1398
 */
1780 jermar 1399
int used_space_insert(as_area_t *a, uintptr_t page, count_t count)
1387 jermar 1400
{
1401
    btree_node_t *leaf, *node;
1402
    count_t pages;
2745 decky 1403
    unsigned int i;
1387 jermar 1404
 
1405
    ASSERT(page == ALIGN_DOWN(page, PAGE_SIZE));
1406
    ASSERT(count);
1407
 
1408
    pages = (count_t) btree_search(&a->used_space, page, &leaf);
1409
    if (pages) {
1410
        /*
1411
         * We hit the beginning of some used space.
1412
         */
1413
        return 0;
1414
    }
1415
 
1437 jermar 1416
    if (!leaf->keys) {
1417
        btree_insert(&a->used_space, page, (void *) count, leaf);
1418
        return 1;
1419
    }
1420
 
1387 jermar 1421
    node = btree_leaf_node_left_neighbour(&a->used_space, leaf);
1422
    if (node) {
2087 jermar 1423
        uintptr_t left_pg = node->key[node->keys - 1];
1424
        uintptr_t right_pg = leaf->key[0];
1425
        count_t left_cnt = (count_t) node->value[node->keys - 1];
1426
        count_t right_cnt = (count_t) leaf->value[0];
1387 jermar 1427
 
1428
        /*
1429
         * Examine the possibility that the interval fits
1430
         * somewhere between the rightmost interval of
1431
         * the left neigbour and the first interval of the leaf.
1432
         */
1433
 
1434
        if (page >= right_pg) {
1435
            /* Do nothing. */
2087 jermar 1436
        } else if (overlaps(page, count * PAGE_SIZE, left_pg,
1437
            left_cnt * PAGE_SIZE)) {
1387 jermar 1438
            /* The interval intersects with the left interval. */
1439
            return 0;
2087 jermar 1440
        } else if (overlaps(page, count * PAGE_SIZE, right_pg,
1441
            right_cnt * PAGE_SIZE)) {
1387 jermar 1442
            /* The interval intersects with the right interval. */
1443
            return 0;          
2087 jermar 1444
        } else if ((page == left_pg + left_cnt * PAGE_SIZE) &&
1445
            (page + count * PAGE_SIZE == right_pg)) {
1446
            /*
1447
             * The interval can be added by merging the two already
1448
             * present intervals.
1449
             */
1403 jermar 1450
            node->value[node->keys - 1] += count + right_cnt;
1387 jermar 1451
            btree_remove(&a->used_space, right_pg, leaf);
1452
            return 1;
2087 jermar 1453
        } else if (page == left_pg + left_cnt * PAGE_SIZE) {
1454
            /*
1455
             * The interval can be added by simply growing the left
1456
             * interval.
1457
             */
1403 jermar 1458
            node->value[node->keys - 1] += count;
1387 jermar 1459
            return 1;
2087 jermar 1460
        } else if (page + count * PAGE_SIZE == right_pg) {
1387 jermar 1461
            /*
2087 jermar 1462
             * The interval can be addded by simply moving base of
1463
             * the right interval down and increasing its size
1464
             * accordingly.
1387 jermar 1465
             */
1403 jermar 1466
            leaf->value[0] += count;
1387 jermar 1467
            leaf->key[0] = page;
1468
            return 1;
1469
        } else {
1470
            /*
1471
             * The interval is between both neigbouring intervals,
1472
             * but cannot be merged with any of them.
1473
             */
2087 jermar 1474
            btree_insert(&a->used_space, page, (void *) count,
1475
                leaf);
1387 jermar 1476
            return 1;
1477
        }
1478
    } else if (page < leaf->key[0]) {
1780 jermar 1479
        uintptr_t right_pg = leaf->key[0];
1387 jermar 1480
        count_t right_cnt = (count_t) leaf->value[0];
1481
 
1482
        /*
2087 jermar 1483
         * Investigate the border case in which the left neighbour does
1484
         * not exist but the interval fits from the left.
1387 jermar 1485
         */
1486
 
2087 jermar 1487
        if (overlaps(page, count * PAGE_SIZE, right_pg,
1488
            right_cnt * PAGE_SIZE)) {
1387 jermar 1489
            /* The interval intersects with the right interval. */
1490
            return 0;
2087 jermar 1491
        } else if (page + count * PAGE_SIZE == right_pg) {
1387 jermar 1492
            /*
2087 jermar 1493
             * The interval can be added by moving the base of the
1494
             * right interval down and increasing its size
1495
             * accordingly.
1387 jermar 1496
             */
1497
            leaf->key[0] = page;
1403 jermar 1498
            leaf->value[0] += count;
1387 jermar 1499
            return 1;
1500
        } else {
1501
            /*
1502
             * The interval doesn't adjoin with the right interval.
1503
             * It must be added individually.
1504
             */
2087 jermar 1505
            btree_insert(&a->used_space, page, (void *) count,
1506
                leaf);
1387 jermar 1507
            return 1;
1508
        }
1509
    }
1510
 
1511
    node = btree_leaf_node_right_neighbour(&a->used_space, leaf);
1512
    if (node) {
2087 jermar 1513
        uintptr_t left_pg = leaf->key[leaf->keys - 1];
1514
        uintptr_t right_pg = node->key[0];
1515
        count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
1516
        count_t right_cnt = (count_t) node->value[0];
1387 jermar 1517
 
1518
        /*
1519
         * Examine the possibility that the interval fits
1520
         * somewhere between the leftmost interval of
1521
         * the right neigbour and the last interval of the leaf.
1522
         */
1523
 
1524
        if (page < left_pg) {
1525
            /* Do nothing. */
2087 jermar 1526
        } else if (overlaps(page, count * PAGE_SIZE, left_pg,
1527
            left_cnt * PAGE_SIZE)) {
1387 jermar 1528
            /* The interval intersects with the left interval. */
1529
            return 0;
2087 jermar 1530
        } else if (overlaps(page, count * PAGE_SIZE, right_pg,
1531
            right_cnt * PAGE_SIZE)) {
1387 jermar 1532
            /* The interval intersects with the right interval. */
1533
            return 0;          
2087 jermar 1534
        } else if ((page == left_pg + left_cnt * PAGE_SIZE) &&
1535
            (page + count * PAGE_SIZE == right_pg)) {
1536
            /*
1537
             * The interval can be added by merging the two already
1538
             * present intervals.
1539
             * */
1403 jermar 1540
            leaf->value[leaf->keys - 1] += count + right_cnt;
1387 jermar 1541
            btree_remove(&a->used_space, right_pg, node);
1542
            return 1;
2087 jermar 1543
        } else if (page == left_pg + left_cnt * PAGE_SIZE) {
1544
            /*
1545
             * The interval can be added by simply growing the left
1546
             * interval.
1547
             * */
1403 jermar 1548
            leaf->value[leaf->keys - 1] +=  count;
1387 jermar 1549
            return 1;
2087 jermar 1550
        } else if (page + count * PAGE_SIZE == right_pg) {
1387 jermar 1551
            /*
2087 jermar 1552
             * The interval can be addded by simply moving base of
1553
             * the right interval down and increasing its size
1554
             * accordingly.
1387 jermar 1555
             */
1403 jermar 1556
            node->value[0] += count;
1387 jermar 1557
            node->key[0] = page;
1558
            return 1;
1559
        } else {
1560
            /*
1561
             * The interval is between both neigbouring intervals,
1562
             * but cannot be merged with any of them.
1563
             */
2087 jermar 1564
            btree_insert(&a->used_space, page, (void *) count,
1565
                leaf);
1387 jermar 1566
            return 1;
1567
        }
1568
    } else if (page >= leaf->key[leaf->keys - 1]) {
1780 jermar 1569
        uintptr_t left_pg = leaf->key[leaf->keys - 1];
1387 jermar 1570
        count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
1571
 
1572
        /*
2087 jermar 1573
         * Investigate the border case in which the right neighbour
1574
         * does not exist but the interval fits from the right.
1387 jermar 1575
         */
1576
 
2087 jermar 1577
        if (overlaps(page, count * PAGE_SIZE, left_pg,
1578
            left_cnt * PAGE_SIZE)) {
1403 jermar 1579
            /* The interval intersects with the left interval. */
1387 jermar 1580
            return 0;
2087 jermar 1581
        } else if (left_pg + left_cnt * PAGE_SIZE == page) {
1582
            /*
1583
             * The interval can be added by growing the left
1584
             * interval.
1585
             */
1403 jermar 1586
            leaf->value[leaf->keys - 1] += count;
1387 jermar 1587
            return 1;
1588
        } else {
1589
            /*
1590
             * The interval doesn't adjoin with the left interval.
1591
             * It must be added individually.
1592
             */
2087 jermar 1593
            btree_insert(&a->used_space, page, (void *) count,
1594
                leaf);
1387 jermar 1595
            return 1;
1596
        }
1597
    }
1598
 
1599
    /*
2087 jermar 1600
     * Note that if the algorithm made it thus far, the interval can fit
1601
     * only between two other intervals of the leaf. The two border cases
1602
     * were already resolved.
1387 jermar 1603
     */
1604
    for (i = 1; i < leaf->keys; i++) {
1605
        if (page < leaf->key[i]) {
2087 jermar 1606
            uintptr_t left_pg = leaf->key[i - 1];
1607
            uintptr_t right_pg = leaf->key[i];
1608
            count_t left_cnt = (count_t) leaf->value[i - 1];
1609
            count_t right_cnt = (count_t) leaf->value[i];
1387 jermar 1610
 
1611
            /*
1612
             * The interval fits between left_pg and right_pg.
1613
             */
1614
 
2087 jermar 1615
            if (overlaps(page, count * PAGE_SIZE, left_pg,
1616
                left_cnt * PAGE_SIZE)) {
1617
                /*
1618
                 * The interval intersects with the left
1619
                 * interval.
1620
                 */
1387 jermar 1621
                return 0;
2087 jermar 1622
            } else if (overlaps(page, count * PAGE_SIZE, right_pg,
1623
                right_cnt * PAGE_SIZE)) {
1624
                /*
1625
                 * The interval intersects with the right
1626
                 * interval.
1627
                 */
1387 jermar 1628
                return 0;          
2087 jermar 1629
            } else if ((page == left_pg + left_cnt * PAGE_SIZE) &&
1630
                (page + count * PAGE_SIZE == right_pg)) {
1631
                /*
1632
                 * The interval can be added by merging the two
1633
                 * already present intervals.
1634
                 */
1403 jermar 1635
                leaf->value[i - 1] += count + right_cnt;
1387 jermar 1636
                btree_remove(&a->used_space, right_pg, leaf);
1637
                return 1;
2087 jermar 1638
            } else if (page == left_pg + left_cnt * PAGE_SIZE) {
1639
                /*
1640
                 * The interval can be added by simply growing
1641
                 * the left interval.
1642
                 */
1403 jermar 1643
                leaf->value[i - 1] += count;
1387 jermar 1644
                return 1;
2087 jermar 1645
            } else if (page + count * PAGE_SIZE == right_pg) {
1387 jermar 1646
                /*
2087 jermar 1647
                     * The interval can be addded by simply moving
1648
                 * base of the right interval down and
1649
                 * increasing its size accordingly.
1387 jermar 1650
                 */
1403 jermar 1651
                leaf->value[i] += count;
1387 jermar 1652
                leaf->key[i] = page;
1653
                return 1;
1654
            } else {
1655
                /*
2087 jermar 1656
                 * The interval is between both neigbouring
1657
                 * intervals, but cannot be merged with any of
1658
                 * them.
1387 jermar 1659
                 */
2087 jermar 1660
                btree_insert(&a->used_space, page,
1661
                    (void *) count, leaf);
1387 jermar 1662
                return 1;
1663
            }
1664
        }
1665
    }
1666
 
3425 svoboda 1667
    panic("Inconsistency detected while adding %" PRIc " pages of used "
4377 svoboda 1668
        "space at %p.", count, page);
1387 jermar 1669
}
1670
 
1671
/** Mark portion of address space area as unused.
1672
 *
1673
 * The address space area must be already locked.
1674
 *
3425 svoboda 1675
 * @param a     Address space area.
1676
 * @param page      First page to be marked.
1677
 * @param count     Number of page to be marked.
1387 jermar 1678
 *
3425 svoboda 1679
 * @return      Zero on failure and non-zero on success.
1387 jermar 1680
 */
1780 jermar 1681
int used_space_remove(as_area_t *a, uintptr_t page, count_t count)
1387 jermar 1682
{
1683
    btree_node_t *leaf, *node;
1684
    count_t pages;
2745 decky 1685
    unsigned int i;
1387 jermar 1686
 
1687
    ASSERT(page == ALIGN_DOWN(page, PAGE_SIZE));
1688
    ASSERT(count);
1689
 
1690
    pages = (count_t) btree_search(&a->used_space, page, &leaf);
1691
    if (pages) {
1692
        /*
1693
         * We are lucky, page is the beginning of some interval.
1694
         */
1695
        if (count > pages) {
1696
            return 0;
1697
        } else if (count == pages) {
1698
            btree_remove(&a->used_space, page, leaf);
1403 jermar 1699
            return 1;
1387 jermar 1700
        } else {
1701
            /*
1702
             * Find the respective interval.
1703
             * Decrease its size and relocate its start address.
1704
             */
1705
            for (i = 0; i < leaf->keys; i++) {
1706
                if (leaf->key[i] == page) {
2087 jermar 1707
                    leaf->key[i] += count * PAGE_SIZE;
1403 jermar 1708
                    leaf->value[i] -= count;
1387 jermar 1709
                    return 1;
1710
                }
1711
            }
1712
            goto error;
1713
        }
1714
    }
1715
 
1716
    node = btree_leaf_node_left_neighbour(&a->used_space, leaf);
1717
    if (node && page < leaf->key[0]) {
1780 jermar 1718
        uintptr_t left_pg = node->key[node->keys - 1];
1387 jermar 1719
        count_t left_cnt = (count_t) node->value[node->keys - 1];
1720
 
2087 jermar 1721
        if (overlaps(left_pg, left_cnt * PAGE_SIZE, page,
1722
            count * PAGE_SIZE)) {
1723
            if (page + count * PAGE_SIZE ==
1724
                left_pg + left_cnt * PAGE_SIZE) {
1387 jermar 1725
                /*
2087 jermar 1726
                 * The interval is contained in the rightmost
1727
                 * interval of the left neighbour and can be
1728
                 * removed by updating the size of the bigger
1729
                 * interval.
1387 jermar 1730
                 */
1403 jermar 1731
                node->value[node->keys - 1] -= count;
1387 jermar 1732
                return 1;
2087 jermar 1733
            } else if (page + count * PAGE_SIZE <
1734
                left_pg + left_cnt*PAGE_SIZE) {
1403 jermar 1735
                count_t new_cnt;
1387 jermar 1736
 
1737
                /*
2087 jermar 1738
                 * The interval is contained in the rightmost
1739
                 * interval of the left neighbour but its
1740
                 * removal requires both updating the size of
1741
                 * the original interval and also inserting a
1742
                 * new interval.
1387 jermar 1743
                 */
2087 jermar 1744
                new_cnt = ((left_pg + left_cnt * PAGE_SIZE) -
1745
                    (page + count*PAGE_SIZE)) >> PAGE_WIDTH;
1403 jermar 1746
                node->value[node->keys - 1] -= count + new_cnt;
2087 jermar 1747
                btree_insert(&a->used_space, page +
1748
                    count * PAGE_SIZE, (void *) new_cnt, leaf);
1387 jermar 1749
                return 1;
1750
            }
1751
        }
1752
        return 0;
1753
    } else if (page < leaf->key[0]) {
1754
        return 0;
1755
    }
1756
 
1757
    if (page > leaf->key[leaf->keys - 1]) {
1780 jermar 1758
        uintptr_t left_pg = leaf->key[leaf->keys - 1];
1387 jermar 1759
        count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
1760
 
2087 jermar 1761
        if (overlaps(left_pg, left_cnt * PAGE_SIZE, page,
1762
            count * PAGE_SIZE)) {
1763
            if (page + count * PAGE_SIZE ==
1764
                left_pg + left_cnt * PAGE_SIZE) {
1387 jermar 1765
                /*
2087 jermar 1766
                 * The interval is contained in the rightmost
1767
                 * interval of the leaf and can be removed by
1768
                 * updating the size of the bigger interval.
1387 jermar 1769
                 */
1403 jermar 1770
                leaf->value[leaf->keys - 1] -= count;
1387 jermar 1771
                return 1;
2087 jermar 1772
            } else if (page + count * PAGE_SIZE < left_pg +
1773
                left_cnt * PAGE_SIZE) {
1403 jermar 1774
                count_t new_cnt;
1387 jermar 1775
 
1776
                /*
2087 jermar 1777
                 * The interval is contained in the rightmost
1778
                 * interval of the leaf but its removal
1779
                 * requires both updating the size of the
1780
                 * original interval and also inserting a new
1781
                 * interval.
1387 jermar 1782
                 */
2087 jermar 1783
                new_cnt = ((left_pg + left_cnt * PAGE_SIZE) -
1784
                    (page + count * PAGE_SIZE)) >> PAGE_WIDTH;
1403 jermar 1785
                leaf->value[leaf->keys - 1] -= count + new_cnt;
2087 jermar 1786
                btree_insert(&a->used_space, page +
1787
                    count * PAGE_SIZE, (void *) new_cnt, leaf);
1387 jermar 1788
                return 1;
1789
            }
1790
        }
1791
        return 0;
1792
    }  
1793
 
1794
    /*
1795
     * The border cases have been already resolved.
1796
     * Now the interval can be only between intervals of the leaf.
1797
     */
1798
    for (i = 1; i < leaf->keys - 1; i++) {
1799
        if (page < leaf->key[i]) {
1780 jermar 1800
            uintptr_t left_pg = leaf->key[i - 1];
1387 jermar 1801
            count_t left_cnt = (count_t) leaf->value[i - 1];
1802
 
1803
            /*
2087 jermar 1804
             * Now the interval is between intervals corresponding
1805
             * to (i - 1) and i.
1387 jermar 1806
             */
2087 jermar 1807
            if (overlaps(left_pg, left_cnt * PAGE_SIZE, page,
1808
                count * PAGE_SIZE)) {
1809
                if (page + count * PAGE_SIZE ==
1810
                    left_pg + left_cnt*PAGE_SIZE) {
1387 jermar 1811
                    /*
2087 jermar 1812
                     * The interval is contained in the
1813
                     * interval (i - 1) of the leaf and can
1814
                     * be removed by updating the size of
1815
                     * the bigger interval.
1387 jermar 1816
                     */
1403 jermar 1817
                    leaf->value[i - 1] -= count;
1387 jermar 1818
                    return 1;
2087 jermar 1819
                } else if (page + count * PAGE_SIZE <
1820
                    left_pg + left_cnt * PAGE_SIZE) {
1403 jermar 1821
                    count_t new_cnt;
1387 jermar 1822
 
1823
                    /*
2087 jermar 1824
                     * The interval is contained in the
1825
                     * interval (i - 1) of the leaf but its
1826
                     * removal requires both updating the
1827
                     * size of the original interval and
1387 jermar 1828
                     * also inserting a new interval.
1829
                     */
2087 jermar 1830
                    new_cnt = ((left_pg +
1831
                        left_cnt * PAGE_SIZE) -
1832
                        (page + count * PAGE_SIZE)) >>
1833
                        PAGE_WIDTH;
1403 jermar 1834
                    leaf->value[i - 1] -= count + new_cnt;
2087 jermar 1835
                    btree_insert(&a->used_space, page +
1836
                        count * PAGE_SIZE, (void *) new_cnt,
1837
                        leaf);
1387 jermar 1838
                    return 1;
1839
                }
1840
            }
1841
            return 0;
1842
        }
1843
    }
1844
 
1845
error:
3425 svoboda 1846
    panic("Inconsistency detected while removing %" PRIc " pages of used "
4377 svoboda 1847
        "space from %p.", count, page);
1387 jermar 1848
}
1849
 
1409 jermar 1850
/** Remove reference to address space area share info.
1851
 *
1852
 * If the reference count drops to 0, the sh_info is deallocated.
1853
 *
3425 svoboda 1854
 * @param sh_info   Pointer to address space area share info.
1409 jermar 1855
 */
1856
void sh_info_remove_reference(share_info_t *sh_info)
1857
{
1858
    bool dealloc = false;
1859
 
1860
    mutex_lock(&sh_info->lock);
1861
    ASSERT(sh_info->refcount);
1862
    if (--sh_info->refcount == 0) {
1863
        dealloc = true;
1495 jermar 1864
        link_t *cur;
1409 jermar 1865
 
1866
        /*
1867
         * Now walk carefully the pagemap B+tree and free/remove
1868
         * reference from all frames found there.
1869
         */
2087 jermar 1870
        for (cur = sh_info->pagemap.leaf_head.next;
1871
            cur != &sh_info->pagemap.leaf_head; cur = cur->next) {
1409 jermar 1872
            btree_node_t *node;
2745 decky 1873
            unsigned int i;
1409 jermar 1874
 
1495 jermar 1875
            node = list_get_instance(cur, btree_node_t, leaf_link);
1876
            for (i = 0; i < node->keys; i++)
1780 jermar 1877
                frame_free((uintptr_t) node->value[i]);
1409 jermar 1878
        }
1879
 
1880
    }
1881
    mutex_unlock(&sh_info->lock);
1882
 
1883
    if (dealloc) {
1884
        btree_destroy(&sh_info->pagemap);
1885
        free(sh_info);
1886
    }
1887
}
1888
 
1235 jermar 1889
/*
1890
 * Address space related syscalls.
1891
 */
1892
 
1893
/** Wrapper for as_area_create(). */
1780 jermar 1894
unative_t sys_as_area_create(uintptr_t address, size_t size, int flags)
1235 jermar 1895
{
2087 jermar 1896
    if (as_area_create(AS, flags | AS_AREA_CACHEABLE, size, address,
1897
        AS_AREA_ATTR_NONE, &anon_backend, NULL))
1780 jermar 1898
        return (unative_t) address;
1235 jermar 1899
    else
1780 jermar 1900
        return (unative_t) -1;
1235 jermar 1901
}
1902
 
1793 jermar 1903
/** Wrapper for as_area_resize(). */
1780 jermar 1904
unative_t sys_as_area_resize(uintptr_t address, size_t size, int flags)
1235 jermar 1905
{
1780 jermar 1906
    return (unative_t) as_area_resize(AS, address, size, 0);
1235 jermar 1907
}
1908
 
3425 svoboda 1909
/** Wrapper for as_area_change_flags(). */
1910
unative_t sys_as_area_change_flags(uintptr_t address, int flags)
1911
{
1912
    return (unative_t) as_area_change_flags(AS, flags, address);
1913
}
1914
 
1793 jermar 1915
/** Wrapper for as_area_destroy(). */
1780 jermar 1916
unative_t sys_as_area_destroy(uintptr_t address)
1306 jermar 1917
{
1780 jermar 1918
    return (unative_t) as_area_destroy(AS, address);
1306 jermar 1919
}
1702 cejka 1920
 
1914 jermar 1921
/** Print out information about address space.
1922
 *
3425 svoboda 1923
 * @param as        Address space.
1914 jermar 1924
 */
1925
void as_print(as_t *as)
1926
{
1927
    ipl_t ipl;
1928
 
1929
    ipl = interrupts_disable();
1930
    mutex_lock(&as->lock);
1931
 
1932
    /* print out info about address space areas */
1933
    link_t *cur;
2087 jermar 1934
    for (cur = as->as_area_btree.leaf_head.next;
1935
        cur != &as->as_area_btree.leaf_head; cur = cur->next) {
1936
        btree_node_t *node;
1914 jermar 1937
 
2087 jermar 1938
        node = list_get_instance(cur, btree_node_t, leaf_link);
1939
 
2745 decky 1940
        unsigned int i;
1914 jermar 1941
        for (i = 0; i < node->keys; i++) {
1915 jermar 1942
            as_area_t *area = node->value[i];
1914 jermar 1943
 
1944
            mutex_lock(&area->lock);
3425 svoboda 1945
            printf("as_area: %p, base=%p, pages=%" PRIc
1946
                " (%p - %p)\n", area, area->base, area->pages,
1947
                area->base, area->base + FRAMES2SIZE(area->pages));
1914 jermar 1948
            mutex_unlock(&area->lock);
1949
        }
1950
    }
1951
 
1952
    mutex_unlock(&as->lock);
1953
    interrupts_restore(ipl);
1954
}
1955
 
1757 jermar 1956
/** @}
1702 cejka 1957
 */