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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
 
3403 svoboda 114
static int area_flags_to_page_flags(int);
115
static as_area_t *find_area_and_lock(as_t *, uintptr_t);
116
static bool check_area_conflicts(as_t *, uintptr_t, size_t, as_area_t *);
117
static void sh_info_remove_reference(share_info_t *);
703 jermar 118
 
1891 jermar 119
static int as_constructor(void *obj, int flags)
120
{
121
    as_t *as = (as_t *) obj;
122
    int rc;
123
 
124
    link_initialize(&as->inactive_as_with_asid_link);
3191 svoboda 125
    mutex_initialize(&as->lock, MUTEX_PASSIVE);
1891 jermar 126
 
127
    rc = as_constructor_arch(as, flags);
128
 
129
    return rc;
130
}
131
 
132
static int as_destructor(void *obj)
133
{
134
    as_t *as = (as_t *) obj;
135
 
136
    return as_destructor_arch(as);
137
}
138
 
756 jermar 139
/** Initialize address space subsystem. */
140
void as_init(void)
141
{
142
    as_arch_init();
2126 decky 143
 
1891 jermar 144
    as_slab = slab_cache_create("as_slab", sizeof(as_t), 0,
2087 jermar 145
        as_constructor, as_destructor, SLAB_CACHE_MAGDEFERRED);
1890 jermar 146
 
789 palkovsky 147
    AS_KERNEL = as_create(FLAG_AS_KERNEL);
1383 decky 148
    if (!AS_KERNEL)
149
        panic("can't create kernel address space\n");
150
 
756 jermar 151
}
152
 
757 jermar 153
/** Create address space.
154
 *
3403 svoboda 155
 * @param flags     Flags that influence the way in wich the address space
156
 *          is created.
757 jermar 157
 */
756 jermar 158
as_t *as_create(int flags)
703 jermar 159
{
160
    as_t *as;
161
 
1890 jermar 162
    as = (as_t *) slab_alloc(as_slab, 0);
1891 jermar 163
    (void) as_create_arch(as, 0);
164
 
1147 jermar 165
    btree_create(&as->as_area_btree);
822 palkovsky 166
 
167
    if (flags & FLAG_AS_KERNEL)
168
        as->asid = ASID_KERNEL;
169
    else
170
        as->asid = ASID_INVALID;
171
 
2183 jermar 172
    atomic_set(&as->refcount, 0);
1415 jermar 173
    as->cpu_refcount = 0;
2089 decky 174
#ifdef AS_PAGE_TABLE
2106 jermar 175
    as->genarch.page_table = page_table_create(flags);
2089 decky 176
#else
177
    page_table_create(flags);
178
#endif
703 jermar 179
 
180
    return as;
181
}
182
 
1468 jermar 183
/** Destroy adress space.
184
 *
2087 jermar 185
 * When there are no tasks referencing this address space (i.e. its refcount is
186
 * zero), the address space can be destroyed.
2183 jermar 187
 *
188
 * We know that we don't hold any spinlock.
3403 svoboda 189
 *
190
 * @param as        Address space to be destroyed.
1468 jermar 191
 */
192
void as_destroy(as_t *as)
973 palkovsky 193
{
1468 jermar 194
    ipl_t ipl;
1594 jermar 195
    bool cond;
2183 jermar 196
    DEADLOCK_PROBE_INIT(p_asidlock);
973 palkovsky 197
 
2183 jermar 198
    ASSERT(atomic_get(&as->refcount) == 0);
1468 jermar 199
 
200
    /*
201
     * Since there is no reference to this area,
202
     * it is safe not to lock its mutex.
203
     */
2170 jermar 204
 
2183 jermar 205
    /*
206
     * We need to avoid deadlock between TLB shootdown and asidlock.
207
     * We therefore try to take asid conditionally and if we don't succeed,
208
     * we enable interrupts and try again. This is done while preemption is
209
     * disabled to prevent nested context switches. We also depend on the
210
     * fact that so far no spinlocks are held.
211
     */
212
    preemption_disable();
213
    ipl = interrupts_read();
214
retry:
215
    interrupts_disable();
216
    if (!spinlock_trylock(&asidlock)) {
217
        interrupts_enable();
218
        DEADLOCK_PROBE(p_asidlock, DEADLOCK_THRESHOLD);
219
        goto retry;
220
    }
221
    preemption_enable();    /* Interrupts disabled, enable preemption */
1587 jermar 222
    if (as->asid != ASID_INVALID && as != AS_KERNEL) {
1594 jermar 223
        if (as != AS && as->cpu_refcount == 0)
1587 jermar 224
            list_remove(&as->inactive_as_with_asid_link);
1468 jermar 225
        asid_put(as->asid);
226
    }
2170 jermar 227
    spinlock_unlock(&asidlock);
1468 jermar 228
 
229
    /*
230
     * Destroy address space areas of the address space.
1954 jermar 231
     * The B+tree must be walked carefully because it is
1594 jermar 232
     * also being destroyed.
1468 jermar 233
     */
1594 jermar 234
    for (cond = true; cond; ) {
1468 jermar 235
        btree_node_t *node;
1594 jermar 236
 
237
        ASSERT(!list_empty(&as->as_area_btree.leaf_head));
2087 jermar 238
        node = list_get_instance(as->as_area_btree.leaf_head.next,
239
            btree_node_t, leaf_link);
1594 jermar 240
 
241
        if ((cond = node->keys)) {
242
            as_area_destroy(as, node->key[0]);
243
        }
1468 jermar 244
    }
1495 jermar 245
 
1483 jermar 246
    btree_destroy(&as->as_area_btree);
2089 decky 247
#ifdef AS_PAGE_TABLE
2106 jermar 248
    page_table_destroy(as->genarch.page_table);
2089 decky 249
#else
250
    page_table_destroy(NULL);
251
#endif
1468 jermar 252
 
253
    interrupts_restore(ipl);
2126 decky 254
 
1890 jermar 255
    slab_free(as_slab, as);
973 palkovsky 256
}
257
 
703 jermar 258
/** Create address space area of common attributes.
259
 *
260
 * The created address space area is added to the target address space.
261
 *
3403 svoboda 262
 * @param as        Target address space.
263
 * @param flags     Flags of the area memory.
264
 * @param size      Size of area.
265
 * @param base      Base address of area.
266
 * @param attrs     Attributes of the area.
267
 * @param backend   Address space area backend. NULL if no backend is used.
268
 * @param backend_data  NULL or a pointer to an array holding two void *.
703 jermar 269
 *
3403 svoboda 270
 * @return      Address space area on success or NULL on failure.
703 jermar 271
 */
2069 jermar 272
as_area_t *
273
as_area_create(as_t *as, int flags, size_t size, uintptr_t base, int attrs,
3403 svoboda 274
    mem_backend_t *backend, mem_backend_data_t *backend_data)
703 jermar 275
{
276
    ipl_t ipl;
277
    as_area_t *a;
278
 
279
    if (base % PAGE_SIZE)
1048 jermar 280
        return NULL;
281
 
1233 jermar 282
    if (!size)
283
        return NULL;
284
 
1048 jermar 285
    /* Writeable executable areas are not supported. */
286
    if ((flags & AS_AREA_EXEC) && (flags & AS_AREA_WRITE))
287
        return NULL;
703 jermar 288
 
289
    ipl = interrupts_disable();
1380 jermar 290
    mutex_lock(&as->lock);
703 jermar 291
 
1048 jermar 292
    if (!check_area_conflicts(as, base, size, NULL)) {
1380 jermar 293
        mutex_unlock(&as->lock);
1048 jermar 294
        interrupts_restore(ipl);
295
        return NULL;
296
    }
703 jermar 297
 
822 palkovsky 298
    a = (as_area_t *) malloc(sizeof(as_area_t), 0);
703 jermar 299
 
3191 svoboda 300
    mutex_initialize(&a->lock, MUTEX_PASSIVE);
822 palkovsky 301
 
1424 jermar 302
    a->as = as;
1026 jermar 303
    a->flags = flags;
1239 jermar 304
    a->attributes = attrs;
1048 jermar 305
    a->pages = SIZE2FRAMES(size);
822 palkovsky 306
    a->base = base;
1409 jermar 307
    a->sh_info = NULL;
308
    a->backend = backend;
1424 jermar 309
    if (backend_data)
310
        a->backend_data = *backend_data;
311
    else
3153 svoboda 312
        memsetb(&a->backend_data, sizeof(a->backend_data), 0);
1424 jermar 313
 
1387 jermar 314
    btree_create(&a->used_space);
822 palkovsky 315
 
1147 jermar 316
    btree_insert(&as->as_area_btree, base, (void *) a, NULL);
822 palkovsky 317
 
1380 jermar 318
    mutex_unlock(&as->lock);
703 jermar 319
    interrupts_restore(ipl);
704 jermar 320
 
703 jermar 321
    return a;
322
}
323
 
1235 jermar 324
/** Find address space area and change it.
325
 *
3403 svoboda 326
 * @param as        Address space.
327
 * @param address   Virtual address belonging to the area to be changed.
328
 *          Must be page-aligned.
329
 * @param size      New size of the virtual memory block starting at
330
 *          address.
331
 * @param flags     Flags influencing the remap operation. Currently unused.
1235 jermar 332
 *
3403 svoboda 333
 * @return      Zero on success or a value from @ref errno.h otherwise.
1235 jermar 334
 */
1780 jermar 335
int as_area_resize(as_t *as, uintptr_t address, size_t size, int flags)
1235 jermar 336
{
1306 jermar 337
    as_area_t *area;
1235 jermar 338
    ipl_t ipl;
339
    size_t pages;
340
 
341
    ipl = interrupts_disable();
1380 jermar 342
    mutex_lock(&as->lock);
1235 jermar 343
 
344
    /*
345
     * Locate the area.
346
     */
347
    area = find_area_and_lock(as, address);
348
    if (!area) {
1380 jermar 349
        mutex_unlock(&as->lock);
1235 jermar 350
        interrupts_restore(ipl);
1306 jermar 351
        return ENOENT;
1235 jermar 352
    }
353
 
1424 jermar 354
    if (area->backend == &phys_backend) {
1235 jermar 355
        /*
356
         * Remapping of address space areas associated
357
         * with memory mapped devices is not supported.
358
         */
1380 jermar 359
        mutex_unlock(&area->lock);
360
        mutex_unlock(&as->lock);
1235 jermar 361
        interrupts_restore(ipl);
1306 jermar 362
        return ENOTSUP;
1235 jermar 363
    }
1409 jermar 364
    if (area->sh_info) {
365
        /*
366
         * Remapping of shared address space areas
367
         * is not supported.
368
         */
369
        mutex_unlock(&area->lock);
370
        mutex_unlock(&as->lock);
371
        interrupts_restore(ipl);
372
        return ENOTSUP;
373
    }
1235 jermar 374
 
375
    pages = SIZE2FRAMES((address - area->base) + size);
376
    if (!pages) {
377
        /*
378
         * Zero size address space areas are not allowed.
379
         */
1380 jermar 380
        mutex_unlock(&area->lock);
381
        mutex_unlock(&as->lock);
1235 jermar 382
        interrupts_restore(ipl);
1306 jermar 383
        return EPERM;
1235 jermar 384
    }
385
 
386
    if (pages < area->pages) {
1403 jermar 387
        bool cond;
3448 svoboda 388
        uintptr_t start_free = area->base + pages * PAGE_SIZE;
1235 jermar 389
 
390
        /*
391
         * Shrinking the area.
392
         * No need to check for overlaps.
393
         */
1403 jermar 394
 
395
        /*
1436 jermar 396
         * Start TLB shootdown sequence.
397
         */
3448 svoboda 398
        tlb_shootdown_start(TLB_INVL_PAGES, as->asid, area->base +
2087 jermar 399
            pages * PAGE_SIZE, area->pages - pages);
1436 jermar 400
 
401
        /*
1403 jermar 402
         * Remove frames belonging to used space starting from
403
         * the highest addresses downwards until an overlap with
404
         * the resized address space area is found. Note that this
405
         * is also the right way to remove part of the used_space
406
         * B+tree leaf list.
407
         */    
408
        for (cond = true; cond;) {
409
            btree_node_t *node;
410
 
411
            ASSERT(!list_empty(&area->used_space.leaf_head));
2087 jermar 412
            node =
413
                list_get_instance(area->used_space.leaf_head.prev,
414
                btree_node_t, leaf_link);
1403 jermar 415
            if ((cond = (bool) node->keys)) {
1780 jermar 416
                uintptr_t b = node->key[node->keys - 1];
2087 jermar 417
                count_t c =
418
                    (count_t) node->value[node->keys - 1];
2745 decky 419
                unsigned int i = 0;
1235 jermar 420
 
2087 jermar 421
                if (overlaps(b, c * PAGE_SIZE, area->base,
2133 jermar 422
                    pages * PAGE_SIZE)) {
1403 jermar 423
 
2087 jermar 424
                    if (b + c * PAGE_SIZE <= start_free) {
1403 jermar 425
                        /*
2087 jermar 426
                         * The whole interval fits
427
                         * completely in the resized
428
                         * address space area.
1403 jermar 429
                         */
430
                        break;
431
                    }
432
 
433
                    /*
2087 jermar 434
                     * Part of the interval corresponding
435
                     * to b and c overlaps with the resized
436
                     * address space area.
1403 jermar 437
                     */
438
 
439
                    cond = false;   /* we are almost done */
440
                    i = (start_free - b) >> PAGE_WIDTH;
3403 svoboda 441
                    if (!used_space_remove(area, start_free,
442
                        c - i))
443
                        panic("Could not remove used "
444
                            "space.\n");
1403 jermar 445
                } else {
446
                    /*
2087 jermar 447
                     * The interval of used space can be
448
                     * completely removed.
1403 jermar 449
                     */
450
                    if (!used_space_remove(area, b, c))
3403 svoboda 451
                        panic("Could not remove used "
452
                            "space.\n");
1403 jermar 453
                }
454
 
455
                for (; i < c; i++) {
456
                    pte_t *pte;
457
 
458
                    page_table_lock(as, false);
2087 jermar 459
                    pte = page_mapping_find(as, b +
460
                        i * PAGE_SIZE);
461
                    ASSERT(pte && PTE_VALID(pte) &&
462
                        PTE_PRESENT(pte));
463
                    if (area->backend &&
464
                        area->backend->frame_free) {
1424 jermar 465
                        area->backend->frame_free(area,
2087 jermar 466
                            b + i * PAGE_SIZE,
467
                            PTE_GET_FRAME(pte));
1409 jermar 468
                    }
2087 jermar 469
                    page_mapping_remove(as, b +
470
                        i * PAGE_SIZE);
1403 jermar 471
                    page_table_unlock(as, false);
472
                }
1235 jermar 473
            }
474
        }
1436 jermar 475
 
1235 jermar 476
        /*
1436 jermar 477
         * Finish TLB shootdown sequence.
1235 jermar 478
         */
2183 jermar 479
 
2087 jermar 480
        tlb_invalidate_pages(as->asid, area->base + pages * PAGE_SIZE,
481
            area->pages - pages);
1889 jermar 482
        /*
483
         * Invalidate software translation caches (e.g. TSB on sparc64).
484
         */
2087 jermar 485
        as_invalidate_translation_cache(as, area->base +
486
            pages * PAGE_SIZE, area->pages - pages);
2183 jermar 487
        tlb_shootdown_finalize();
488
 
1235 jermar 489
    } else {
490
        /*
491
         * Growing the area.
492
         * Check for overlaps with other address space areas.
493
         */
2087 jermar 494
        if (!check_area_conflicts(as, address, pages * PAGE_SIZE,
495
            area)) {
1380 jermar 496
            mutex_unlock(&area->lock);
497
            mutex_unlock(&as->lock);       
1235 jermar 498
            interrupts_restore(ipl);
1306 jermar 499
            return EADDRNOTAVAIL;
1235 jermar 500
        }
501
    }
502
 
503
    area->pages = pages;
504
 
1380 jermar 505
    mutex_unlock(&area->lock);
506
    mutex_unlock(&as->lock);
1235 jermar 507
    interrupts_restore(ipl);
508
 
1306 jermar 509
    return 0;
1235 jermar 510
}
511
 
1306 jermar 512
/** Destroy address space area.
513
 *
3403 svoboda 514
 * @param as        Address space.
515
 * @param address   Address within the area to be deleted.
1306 jermar 516
 *
3403 svoboda 517
 * @return      Zero on success or a value from @ref errno.h on failure.
1306 jermar 518
 */
1780 jermar 519
int as_area_destroy(as_t *as, uintptr_t address)
1306 jermar 520
{
521
    as_area_t *area;
1780 jermar 522
    uintptr_t base;
1495 jermar 523
    link_t *cur;
1306 jermar 524
    ipl_t ipl;
525
 
526
    ipl = interrupts_disable();
1380 jermar 527
    mutex_lock(&as->lock);
1306 jermar 528
 
529
    area = find_area_and_lock(as, address);
530
    if (!area) {
1380 jermar 531
        mutex_unlock(&as->lock);
1306 jermar 532
        interrupts_restore(ipl);
533
        return ENOENT;
534
    }
535
 
1403 jermar 536
    base = area->base;
537
 
1411 jermar 538
    /*
1436 jermar 539
     * Start TLB shootdown sequence.
540
     */
1889 jermar 541
    tlb_shootdown_start(TLB_INVL_PAGES, as->asid, area->base, area->pages);
1436 jermar 542
 
543
    /*
1411 jermar 544
     * Visit only the pages mapped by used_space B+tree.
545
     */
2087 jermar 546
    for (cur = area->used_space.leaf_head.next;
547
        cur != &area->used_space.leaf_head; cur = cur->next) {
1411 jermar 548
        btree_node_t *node;
2745 decky 549
        unsigned int i;
1403 jermar 550
 
1495 jermar 551
        node = list_get_instance(cur, btree_node_t, leaf_link);
552
        for (i = 0; i < node->keys; i++) {
1780 jermar 553
            uintptr_t b = node->key[i];
1495 jermar 554
            count_t j;
1411 jermar 555
            pte_t *pte;
1403 jermar 556
 
1495 jermar 557
            for (j = 0; j < (count_t) node->value[i]; j++) {
1411 jermar 558
                page_table_lock(as, false);
2087 jermar 559
                pte = page_mapping_find(as, b + j * PAGE_SIZE);
560
                ASSERT(pte && PTE_VALID(pte) &&
561
                    PTE_PRESENT(pte));
562
                if (area->backend &&
563
                    area->backend->frame_free) {
564
                    area->backend->frame_free(area, b +
2133 jermar 565
                        j * PAGE_SIZE, PTE_GET_FRAME(pte));
1403 jermar 566
                }
2087 jermar 567
                page_mapping_remove(as, b + j * PAGE_SIZE);            
1411 jermar 568
                page_table_unlock(as, false);
1306 jermar 569
            }
570
        }
571
    }
1403 jermar 572
 
1306 jermar 573
    /*
1436 jermar 574
     * Finish TLB shootdown sequence.
1306 jermar 575
     */
2183 jermar 576
 
1889 jermar 577
    tlb_invalidate_pages(as->asid, area->base, area->pages);
578
    /*
2087 jermar 579
     * Invalidate potential software translation caches (e.g. TSB on
580
     * sparc64).
1889 jermar 581
     */
582
    as_invalidate_translation_cache(as, area->base, area->pages);
2183 jermar 583
    tlb_shootdown_finalize();
1889 jermar 584
 
1436 jermar 585
    btree_destroy(&area->used_space);
1306 jermar 586
 
1309 jermar 587
    area->attributes |= AS_AREA_ATTR_PARTIAL;
1409 jermar 588
 
589
    if (area->sh_info)
590
        sh_info_remove_reference(area->sh_info);
591
 
1380 jermar 592
    mutex_unlock(&area->lock);
1306 jermar 593
 
594
    /*
595
     * Remove the empty area from address space.
596
     */
1889 jermar 597
    btree_remove(&as->as_area_btree, base, NULL);
1306 jermar 598
 
1309 jermar 599
    free(area);
600
 
1889 jermar 601
    mutex_unlock(&as->lock);
1306 jermar 602
    interrupts_restore(ipl);
603
    return 0;
604
}
605
 
1413 jermar 606
/** Share address space area with another or the same address space.
1235 jermar 607
 *
1424 jermar 608
 * Address space area mapping is shared with a new address space area.
609
 * If the source address space area has not been shared so far,
610
 * a new sh_info is created. The new address space area simply gets the
611
 * sh_info of the source area. The process of duplicating the
612
 * mapping is done through the backend share function.
1413 jermar 613
 *
3403 svoboda 614
 * @param src_as    Pointer to source address space.
615
 * @param src_base  Base address of the source address space area.
616
 * @param acc_size  Expected size of the source area.
617
 * @param dst_as    Pointer to destination address space.
618
 * @param dst_base  Target base address.
1417 jermar 619
 * @param dst_flags_mask Destination address space area flags mask.
1235 jermar 620
 *
3403 svoboda 621
 * @return      Zero on success or ENOENT if there is no such task or if
622
 *          there is no such address space area, EPERM if there was
623
 *          a problem in accepting the area or ENOMEM if there was a
624
 *          problem in allocating destination address space area.
625
 *          ENOTSUP is returned if the address space area backend
626
 *          does not support sharing.
1235 jermar 627
 */
1780 jermar 628
int as_area_share(as_t *src_as, uintptr_t src_base, size_t acc_size,
2647 jermar 629
    as_t *dst_as, uintptr_t dst_base, int dst_flags_mask)
1235 jermar 630
{
631
    ipl_t ipl;
1239 jermar 632
    int src_flags;
633
    size_t src_size;
634
    as_area_t *src_area, *dst_area;
1413 jermar 635
    share_info_t *sh_info;
1424 jermar 636
    mem_backend_t *src_backend;
637
    mem_backend_data_t src_backend_data;
1434 palkovsky 638
 
1235 jermar 639
    ipl = interrupts_disable();
1380 jermar 640
    mutex_lock(&src_as->lock);
1329 palkovsky 641
    src_area = find_area_and_lock(src_as, src_base);
1239 jermar 642
    if (!src_area) {
1238 jermar 643
        /*
644
         * Could not find the source address space area.
645
         */
1380 jermar 646
        mutex_unlock(&src_as->lock);
1238 jermar 647
        interrupts_restore(ipl);
648
        return ENOENT;
649
    }
2007 jermar 650
 
1424 jermar 651
    if (!src_area->backend || !src_area->backend->share) {
1413 jermar 652
        /*
1851 jermar 653
         * There is no backend or the backend does not
1424 jermar 654
         * know how to share the area.
1413 jermar 655
         */
656
        mutex_unlock(&src_area->lock);
657
        mutex_unlock(&src_as->lock);
658
        interrupts_restore(ipl);
659
        return ENOTSUP;
660
    }
661
 
1239 jermar 662
    src_size = src_area->pages * PAGE_SIZE;
663
    src_flags = src_area->flags;
1424 jermar 664
    src_backend = src_area->backend;
665
    src_backend_data = src_area->backend_data;
1544 palkovsky 666
 
667
    /* Share the cacheable flag from the original mapping */
668
    if (src_flags & AS_AREA_CACHEABLE)
669
        dst_flags_mask |= AS_AREA_CACHEABLE;
670
 
2087 jermar 671
    if (src_size != acc_size ||
672
        (src_flags & dst_flags_mask) != dst_flags_mask) {
1413 jermar 673
        mutex_unlock(&src_area->lock);
674
        mutex_unlock(&src_as->lock);
1235 jermar 675
        interrupts_restore(ipl);
676
        return EPERM;
677
    }
1413 jermar 678
 
1235 jermar 679
    /*
1413 jermar 680
     * Now we are committed to sharing the area.
1954 jermar 681
     * First, prepare the area for sharing.
1413 jermar 682
     * Then it will be safe to unlock it.
683
     */
684
    sh_info = src_area->sh_info;
685
    if (!sh_info) {
686
        sh_info = (share_info_t *) malloc(sizeof(share_info_t), 0);
3191 svoboda 687
        mutex_initialize(&sh_info->lock, MUTEX_PASSIVE);
1413 jermar 688
        sh_info->refcount = 2;
689
        btree_create(&sh_info->pagemap);
690
        src_area->sh_info = sh_info;
2647 jermar 691
        /*
692
         * Call the backend to setup sharing.
693
         */
694
        src_area->backend->share(src_area);
1413 jermar 695
    } else {
696
        mutex_lock(&sh_info->lock);
697
        sh_info->refcount++;
698
        mutex_unlock(&sh_info->lock);
699
    }
700
 
701
    mutex_unlock(&src_area->lock);
702
    mutex_unlock(&src_as->lock);
703
 
704
    /*
1239 jermar 705
     * Create copy of the source address space area.
706
     * The destination area is created with AS_AREA_ATTR_PARTIAL
707
     * attribute set which prevents race condition with
708
     * preliminary as_page_fault() calls.
1417 jermar 709
     * The flags of the source area are masked against dst_flags_mask
710
     * to support sharing in less privileged mode.
1235 jermar 711
     */
1461 palkovsky 712
    dst_area = as_area_create(dst_as, dst_flags_mask, src_size, dst_base,
2087 jermar 713
        AS_AREA_ATTR_PARTIAL, src_backend, &src_backend_data);
1239 jermar 714
    if (!dst_area) {
1235 jermar 715
        /*
716
         * Destination address space area could not be created.
717
         */
1413 jermar 718
        sh_info_remove_reference(sh_info);
719
 
1235 jermar 720
        interrupts_restore(ipl);
721
        return ENOMEM;
722
    }
2009 jermar 723
 
1235 jermar 724
    /*
1239 jermar 725
     * Now the destination address space area has been
726
     * fully initialized. Clear the AS_AREA_ATTR_PARTIAL
1413 jermar 727
     * attribute and set the sh_info.
1239 jermar 728
     */
2009 jermar 729
    mutex_lock(&dst_as->lock); 
1380 jermar 730
    mutex_lock(&dst_area->lock);
1239 jermar 731
    dst_area->attributes &= ~AS_AREA_ATTR_PARTIAL;
1413 jermar 732
    dst_area->sh_info = sh_info;
1380 jermar 733
    mutex_unlock(&dst_area->lock);
2009 jermar 734
    mutex_unlock(&dst_as->lock);   
735
 
1235 jermar 736
    interrupts_restore(ipl);
737
 
738
    return 0;
739
}
740
 
1423 jermar 741
/** Check access mode for address space area.
742
 *
743
 * The address space area must be locked prior to this call.
744
 *
3403 svoboda 745
 * @param area      Address space area.
746
 * @param access    Access mode.
1423 jermar 747
 *
3403 svoboda 748
 * @return      False if access violates area's permissions, true
749
 *          otherwise.
1423 jermar 750
 */
751
bool as_area_check_access(as_area_t *area, pf_access_t access)
752
{
753
    int flagmap[] = {
754
        [PF_ACCESS_READ] = AS_AREA_READ,
755
        [PF_ACCESS_WRITE] = AS_AREA_WRITE,
756
        [PF_ACCESS_EXEC] = AS_AREA_EXEC
757
    };
758
 
759
    if (!(area->flags & flagmap[access]))
760
        return false;
761
 
762
    return true;
763
}
764
 
3403 svoboda 765
/** Change adress space area flags.
2984 svoboda 766
 *
767
 * The idea is to have the same data, but with a different access mode.
768
 * This is needed e.g. for writing code into memory and then executing it.
769
 * In order for this to work properly, this may copy the data
770
 * into private anonymous memory (unless it's already there).
771
 *
3403 svoboda 772
 * @param as        Address space.
773
 * @param flags     Flags of the area memory.
774
 * @param address   Address withing the area to be changed.
2984 svoboda 775
 *
3403 svoboda 776
 * @return      Zero on success or a value from @ref errno.h on failure.
2984 svoboda 777
 */
778
int as_area_change_flags(as_t *as, int flags, uintptr_t address)
779
{
780
    as_area_t *area;
781
    uintptr_t base;
782
    link_t *cur;
783
    ipl_t ipl;
2985 svoboda 784
    int page_flags;
3156 svoboda 785
    uintptr_t *old_frame;
786
    index_t frame_idx;
787
    count_t used_pages;
2984 svoboda 788
 
2985 svoboda 789
    /* Flags for the new memory mapping */
790
    page_flags = area_flags_to_page_flags(flags);
791
 
2984 svoboda 792
    ipl = interrupts_disable();
793
    mutex_lock(&as->lock);
794
 
795
    area = find_area_and_lock(as, address);
796
    if (!area) {
797
        mutex_unlock(&as->lock);
798
        interrupts_restore(ipl);
799
        return ENOENT;
800
    }
801
 
802
    if (area->sh_info || area->backend != &anon_backend) {
803
        /* Copying shared areas not supported yet */
804
        /* Copying non-anonymous memory not supported yet */
2985 svoboda 805
        mutex_unlock(&area->lock);
2984 svoboda 806
        mutex_unlock(&as->lock);
807
        interrupts_restore(ipl);
808
        return ENOTSUP;
809
    }
810
 
811
    base = area->base;
812
 
813
    /*
3156 svoboda 814
     * Compute total number of used pages in the used_space B+tree
815
     */
816
    used_pages = 0;
817
 
818
    for (cur = area->used_space.leaf_head.next;
819
        cur != &area->used_space.leaf_head; cur = cur->next) {
820
        btree_node_t *node;
821
        unsigned int i;
822
 
823
        node = list_get_instance(cur, btree_node_t, leaf_link);
824
        for (i = 0; i < node->keys; i++) {
825
            used_pages += (count_t) node->value[i];
826
        }
827
    }
828
 
829
    /* An array for storing frame numbers */
830
    old_frame = malloc(used_pages * sizeof(uintptr_t), 0);
831
 
832
    /*
2984 svoboda 833
     * Start TLB shootdown sequence.
834
     */
835
    tlb_shootdown_start(TLB_INVL_PAGES, as->asid, area->base, area->pages);
836
 
837
    /*
3156 svoboda 838
     * Remove used pages from page tables and remember their frame
839
     * numbers.
2984 svoboda 840
     */
3156 svoboda 841
    frame_idx = 0;
842
 
2984 svoboda 843
    for (cur = area->used_space.leaf_head.next;
844
        cur != &area->used_space.leaf_head; cur = cur->next) {
845
        btree_node_t *node;
846
        unsigned int i;
847
 
848
        node = list_get_instance(cur, btree_node_t, leaf_link);
849
        for (i = 0; i < node->keys; i++) {
850
            uintptr_t b = node->key[i];
851
            count_t j;
852
            pte_t *pte;
853
 
854
            for (j = 0; j < (count_t) node->value[i]; j++) {
855
                page_table_lock(as, false);
856
                pte = page_mapping_find(as, b + j * PAGE_SIZE);
857
                ASSERT(pte && PTE_VALID(pte) &&
858
                    PTE_PRESENT(pte));
3156 svoboda 859
                old_frame[frame_idx++] = PTE_GET_FRAME(pte);
2984 svoboda 860
 
3156 svoboda 861
                /* Remove old mapping */
2984 svoboda 862
                page_mapping_remove(as, b + j * PAGE_SIZE);
863
                page_table_unlock(as, false);
864
            }
865
        }
866
    }
867
 
868
    /*
869
     * Finish TLB shootdown sequence.
870
     */
871
 
872
    tlb_invalidate_pages(as->asid, area->base, area->pages);
873
    /*
874
     * Invalidate potential software translation caches (e.g. TSB on
875
     * sparc64).
876
     */
877
    as_invalidate_translation_cache(as, area->base, area->pages);
878
    tlb_shootdown_finalize();
3156 svoboda 879
 
880
    /*
3403 svoboda 881
     * Set the new flags.
882
     */
883
    area->flags = flags;
884
 
885
    /*
3156 svoboda 886
     * Map pages back in with new flags. This step is kept separate
3403 svoboda 887
     * so that the memory area could not be accesed with both the old and
888
     * the new flags at once.
3156 svoboda 889
     */
890
    frame_idx = 0;
891
 
892
    for (cur = area->used_space.leaf_head.next;
893
        cur != &area->used_space.leaf_head; cur = cur->next) {
894
        btree_node_t *node;
895
        unsigned int i;
896
 
897
        node = list_get_instance(cur, btree_node_t, leaf_link);
898
        for (i = 0; i < node->keys; i++) {
899
            uintptr_t b = node->key[i];
900
            count_t j;
901
 
902
            for (j = 0; j < (count_t) node->value[i]; j++) {
903
                page_table_lock(as, false);
904
 
905
                /* Insert the new mapping */
906
                page_mapping_insert(as, b + j * PAGE_SIZE,
907
                    old_frame[frame_idx++], page_flags);
908
 
909
                page_table_unlock(as, false);
910
            }
911
        }
912
    }
913
 
914
    free(old_frame);
915
 
2984 svoboda 916
    mutex_unlock(&area->lock);
917
    mutex_unlock(&as->lock);
918
    interrupts_restore(ipl);
919
 
920
    return 0;
921
}
922
 
923
 
703 jermar 924
/** Handle page fault within the current address space.
925
 *
3403 svoboda 926
 * This is the high-level page fault handler. It decides whether the page fault
927
 * can be resolved by any backend and if so, it invokes the backend to resolve
928
 * the page fault.
1409 jermar 929
 *
703 jermar 930
 * Interrupts are assumed disabled.
931
 *
3403 svoboda 932
 * @param page      Faulting page.
933
 * @param access    Access mode that caused the page fault (i.e.
934
 *          read/write/exec).
935
 * @param istate    Pointer to the interrupted state.
703 jermar 936
 *
3403 svoboda 937
 * @return      AS_PF_FAULT on page fault, AS_PF_OK on success or
938
 *          AS_PF_DEFER if the fault was caused by copy_to_uspace()
939
 *          or copy_from_uspace().
703 jermar 940
 */
1780 jermar 941
int as_page_fault(uintptr_t page, pf_access_t access, istate_t *istate)
703 jermar 942
{
1044 jermar 943
    pte_t *pte;
977 jermar 944
    as_area_t *area;
703 jermar 945
 
1380 jermar 946
    if (!THREAD)
1409 jermar 947
        return AS_PF_FAULT;
1380 jermar 948
 
703 jermar 949
    ASSERT(AS);
1044 jermar 950
 
1380 jermar 951
    mutex_lock(&AS->lock);
977 jermar 952
    area = find_area_and_lock(AS, page);   
703 jermar 953
    if (!area) {
954
        /*
955
         * No area contained mapping for 'page'.
956
         * Signal page fault to low-level handler.
957
         */
1380 jermar 958
        mutex_unlock(&AS->lock);
1288 jermar 959
        goto page_fault;
703 jermar 960
    }
961
 
1239 jermar 962
    if (area->attributes & AS_AREA_ATTR_PARTIAL) {
963
        /*
964
         * The address space area is not fully initialized.
965
         * Avoid possible race by returning error.
966
         */
1380 jermar 967
        mutex_unlock(&area->lock);
968
        mutex_unlock(&AS->lock);
1288 jermar 969
        goto page_fault;       
1239 jermar 970
    }
971
 
1424 jermar 972
    if (!area->backend || !area->backend->page_fault) {
1409 jermar 973
        /*
974
         * The address space area is not backed by any backend
975
         * or the backend cannot handle page faults.
976
         */
977
        mutex_unlock(&area->lock);
978
        mutex_unlock(&AS->lock);
979
        goto page_fault;       
980
    }
1179 jermar 981
 
1044 jermar 982
    page_table_lock(AS, false);
983
 
703 jermar 984
    /*
3403 svoboda 985
     * To avoid race condition between two page faults on the same address,
986
     * we need to make sure the mapping has not been already inserted.
1044 jermar 987
     */
988
    if ((pte = page_mapping_find(AS, page))) {
989
        if (PTE_PRESENT(pte)) {
1423 jermar 990
            if (((access == PF_ACCESS_READ) && PTE_READABLE(pte)) ||
2087 jermar 991
                (access == PF_ACCESS_WRITE && PTE_WRITABLE(pte)) ||
992
                (access == PF_ACCESS_EXEC && PTE_EXECUTABLE(pte))) {
1423 jermar 993
                page_table_unlock(AS, false);
994
                mutex_unlock(&area->lock);
995
                mutex_unlock(&AS->lock);
996
                return AS_PF_OK;
997
            }
1044 jermar 998
        }
999
    }
1409 jermar 1000
 
1044 jermar 1001
    /*
1409 jermar 1002
     * Resort to the backend page fault handler.
703 jermar 1003
     */
1424 jermar 1004
    if (area->backend->page_fault(area, page, access) != AS_PF_OK) {
1409 jermar 1005
        page_table_unlock(AS, false);
1006
        mutex_unlock(&area->lock);
1007
        mutex_unlock(&AS->lock);
1008
        goto page_fault;
1009
    }
703 jermar 1010
 
1044 jermar 1011
    page_table_unlock(AS, false);
1380 jermar 1012
    mutex_unlock(&area->lock);
1013
    mutex_unlock(&AS->lock);
1288 jermar 1014
    return AS_PF_OK;
1015
 
1016
page_fault:
1017
    if (THREAD->in_copy_from_uspace) {
1018
        THREAD->in_copy_from_uspace = false;
2087 jermar 1019
        istate_set_retaddr(istate,
1020
            (uintptr_t) &memcpy_from_uspace_failover_address);
1288 jermar 1021
    } else if (THREAD->in_copy_to_uspace) {
1022
        THREAD->in_copy_to_uspace = false;
2087 jermar 1023
        istate_set_retaddr(istate,
1024
            (uintptr_t) &memcpy_to_uspace_failover_address);
1288 jermar 1025
    } else {
1026
        return AS_PF_FAULT;
1027
    }
1028
 
1029
    return AS_PF_DEFER;
703 jermar 1030
}
1031
 
823 jermar 1032
/** Switch address spaces.
703 jermar 1033
 *
1380 jermar 1034
 * Note that this function cannot sleep as it is essentially a part of
2170 jermar 1035
 * scheduling. Sleeping here would lead to deadlock on wakeup. Another
1036
 * thing which is forbidden in this context is locking the address space.
1380 jermar 1037
 *
2183 jermar 1038
 * When this function is enetered, no spinlocks may be held.
1039
 *
3403 svoboda 1040
 * @param old       Old address space or NULL.
1041
 * @param new       New address space.
703 jermar 1042
 */
2106 jermar 1043
void as_switch(as_t *old_as, as_t *new_as)
703 jermar 1044
{
2183 jermar 1045
    DEADLOCK_PROBE_INIT(p_asidlock);
1046
    preemption_disable();
1047
retry:
1048
    (void) interrupts_disable();
1049
    if (!spinlock_trylock(&asidlock)) {
1050
        /*
1051
         * Avoid deadlock with TLB shootdown.
1052
         * We can enable interrupts here because
1053
         * preemption is disabled. We should not be
1054
         * holding any other lock.
1055
         */
1056
        (void) interrupts_enable();
1057
        DEADLOCK_PROBE(p_asidlock, DEADLOCK_THRESHOLD);
1058
        goto retry;
1059
    }
1060
    preemption_enable();
703 jermar 1061
 
1062
    /*
823 jermar 1063
     * First, take care of the old address space.
1064
     */
2106 jermar 1065
    if (old_as) {
1066
        ASSERT(old_as->cpu_refcount);
1067
        if((--old_as->cpu_refcount == 0) && (old_as != AS_KERNEL)) {
823 jermar 1068
            /*
1069
             * The old address space is no longer active on
1070
             * any processor. It can be appended to the
1071
             * list of inactive address spaces with assigned
1072
             * ASID.
1073
             */
2141 jermar 1074
            ASSERT(old_as->asid != ASID_INVALID);
1075
            list_append(&old_as->inactive_as_with_asid_link,
1076
                &inactive_as_with_asid_head);
823 jermar 1077
        }
1890 jermar 1078
 
1079
        /*
1080
         * Perform architecture-specific tasks when the address space
1081
         * is being removed from the CPU.
1082
         */
2106 jermar 1083
        as_deinstall_arch(old_as);
823 jermar 1084
    }
1085
 
1086
    /*
1087
     * Second, prepare the new address space.
1088
     */
2106 jermar 1089
    if ((new_as->cpu_refcount++ == 0) && (new_as != AS_KERNEL)) {
2170 jermar 1090
        if (new_as->asid != ASID_INVALID)
2106 jermar 1091
            list_remove(&new_as->inactive_as_with_asid_link);
2170 jermar 1092
        else
1093
            new_as->asid = asid_get();
823 jermar 1094
    }
2106 jermar 1095
#ifdef AS_PAGE_TABLE
1096
    SET_PTL0_ADDRESS(new_as->genarch.page_table);
1097
#endif
823 jermar 1098
 
1099
    /*
703 jermar 1100
     * Perform architecture-specific steps.
727 jermar 1101
     * (e.g. write ASID to hardware register etc.)
703 jermar 1102
     */
2106 jermar 1103
    as_install_arch(new_as);
2170 jermar 1104
 
1105
    spinlock_unlock(&asidlock);
703 jermar 1106
 
2106 jermar 1107
    AS = new_as;
703 jermar 1108
}
754 jermar 1109
 
1235 jermar 1110
/** Convert address space area flags to page flags.
754 jermar 1111
 *
3403 svoboda 1112
 * @param aflags    Flags of some address space area.
754 jermar 1113
 *
3403 svoboda 1114
 * @return      Flags to be passed to page_mapping_insert().
754 jermar 1115
 */
1235 jermar 1116
int area_flags_to_page_flags(int aflags)
754 jermar 1117
{
1118
    int flags;
1119
 
1178 jermar 1120
    flags = PAGE_USER | PAGE_PRESENT;
754 jermar 1121
 
1235 jermar 1122
    if (aflags & AS_AREA_READ)
1026 jermar 1123
        flags |= PAGE_READ;
1124
 
1235 jermar 1125
    if (aflags & AS_AREA_WRITE)
1026 jermar 1126
        flags |= PAGE_WRITE;
1127
 
1235 jermar 1128
    if (aflags & AS_AREA_EXEC)
1026 jermar 1129
        flags |= PAGE_EXEC;
1130
 
1424 jermar 1131
    if (aflags & AS_AREA_CACHEABLE)
1178 jermar 1132
        flags |= PAGE_CACHEABLE;
1133
 
754 jermar 1134
    return flags;
1135
}
756 jermar 1136
 
1235 jermar 1137
/** Compute flags for virtual address translation subsytem.
1138
 *
1139
 * The address space area must be locked.
1140
 * Interrupts must be disabled.
1141
 *
3403 svoboda 1142
 * @param a     Address space area.
1235 jermar 1143
 *
3403 svoboda 1144
 * @return      Flags to be used in page_mapping_insert().
1235 jermar 1145
 */
1409 jermar 1146
int as_area_get_flags(as_area_t *a)
1235 jermar 1147
{
1148
    return area_flags_to_page_flags(a->flags);
1149
}
1150
 
756 jermar 1151
/** Create page table.
1152
 *
3403 svoboda 1153
 * Depending on architecture, create either address space private or global page
1154
 * table.
756 jermar 1155
 *
3403 svoboda 1156
 * @param flags     Flags saying whether the page table is for the kernel
1157
 *          address space.
756 jermar 1158
 *
3403 svoboda 1159
 * @return      First entry of the page table.
756 jermar 1160
 */
1161
pte_t *page_table_create(int flags)
1162
{
2125 decky 1163
    ASSERT(as_operations);
1164
    ASSERT(as_operations->page_table_create);
1165
 
1166
    return as_operations->page_table_create(flags);
756 jermar 1167
}
977 jermar 1168
 
1468 jermar 1169
/** Destroy page table.
1170
 *
1171
 * Destroy page table in architecture specific way.
1172
 *
3403 svoboda 1173
 * @param page_table    Physical address of PTL0.
1468 jermar 1174
 */
1175
void page_table_destroy(pte_t *page_table)
1176
{
2125 decky 1177
    ASSERT(as_operations);
1178
    ASSERT(as_operations->page_table_destroy);
1179
 
1180
    as_operations->page_table_destroy(page_table);
1468 jermar 1181
}
1182
 
1044 jermar 1183
/** Lock page table.
1184
 *
1185
 * This function should be called before any page_mapping_insert(),
1186
 * page_mapping_remove() and page_mapping_find().
1187
 *
1188
 * Locking order is such that address space areas must be locked
1189
 * prior to this call. Address space can be locked prior to this
1190
 * call in which case the lock argument is false.
1191
 *
3403 svoboda 1192
 * @param as        Address space.
1193
 * @param lock      If false, do not attempt to lock as->lock.
1044 jermar 1194
 */
1195
void page_table_lock(as_t *as, bool lock)
1196
{
1197
    ASSERT(as_operations);
1198
    ASSERT(as_operations->page_table_lock);
2125 decky 1199
 
1044 jermar 1200
    as_operations->page_table_lock(as, lock);
1201
}
1202
 
1203
/** Unlock page table.
1204
 *
3403 svoboda 1205
 * @param as        Address space.
1206
 * @param unlock    If false, do not attempt to unlock as->lock.
1044 jermar 1207
 */
1208
void page_table_unlock(as_t *as, bool unlock)
1209
{
1210
    ASSERT(as_operations);
1211
    ASSERT(as_operations->page_table_unlock);
2125 decky 1212
 
1044 jermar 1213
    as_operations->page_table_unlock(as, unlock);
1214
}
1215
 
977 jermar 1216
 
1217
/** Find address space area and lock it.
1218
 *
1219
 * The address space must be locked and interrupts must be disabled.
1220
 *
3403 svoboda 1221
 * @param as        Address space.
1222
 * @param va        Virtual address.
977 jermar 1223
 *
3403 svoboda 1224
 * @return      Locked address space area containing va on success or
1225
 *          NULL on failure.
977 jermar 1226
 */
1780 jermar 1227
as_area_t *find_area_and_lock(as_t *as, uintptr_t va)
977 jermar 1228
{
1229
    as_area_t *a;
1147 jermar 1230
    btree_node_t *leaf, *lnode;
2745 decky 1231
    unsigned int i;
977 jermar 1232
 
1147 jermar 1233
    a = (as_area_t *) btree_search(&as->as_area_btree, va, &leaf);
1234
    if (a) {
1235
        /* va is the base address of an address space area */
1380 jermar 1236
        mutex_lock(&a->lock);
1147 jermar 1237
        return a;
1238
    }
1239
 
1240
    /*
1150 jermar 1241
     * Search the leaf node and the righmost record of its left neighbour
1147 jermar 1242
     * to find out whether this is a miss or va belongs to an address
1243
     * space area found there.
1244
     */
1245
 
1246
    /* First, search the leaf node itself. */
1247
    for (i = 0; i < leaf->keys; i++) {
1248
        a = (as_area_t *) leaf->value[i];
1380 jermar 1249
        mutex_lock(&a->lock);
1147 jermar 1250
        if ((a->base <= va) && (va < a->base + a->pages * PAGE_SIZE)) {
1251
            return a;
1252
        }
1380 jermar 1253
        mutex_unlock(&a->lock);
1147 jermar 1254
    }
977 jermar 1255
 
1147 jermar 1256
    /*
1150 jermar 1257
     * Second, locate the left neighbour and test its last record.
1148 jermar 1258
     * Because of its position in the B+tree, it must have base < va.
1147 jermar 1259
     */
2087 jermar 1260
    lnode = btree_leaf_node_left_neighbour(&as->as_area_btree, leaf);
1261
    if (lnode) {
1147 jermar 1262
        a = (as_area_t *) lnode->value[lnode->keys - 1];
1380 jermar 1263
        mutex_lock(&a->lock);
1147 jermar 1264
        if (va < a->base + a->pages * PAGE_SIZE) {
1048 jermar 1265
            return a;
1147 jermar 1266
        }
1380 jermar 1267
        mutex_unlock(&a->lock);
977 jermar 1268
    }
1269
 
1270
    return NULL;
1271
}
1048 jermar 1272
 
1273
/** Check area conflicts with other areas.
1274
 *
1275
 * The address space must be locked and interrupts must be disabled.
1276
 *
3403 svoboda 1277
 * @param as        Address space.
1278
 * @param va        Starting virtual address of the area being tested.
1279
 * @param size      Size of the area being tested.
1280
 * @param avoid_area    Do not touch this area.
1048 jermar 1281
 *
3403 svoboda 1282
 * @return      True if there is no conflict, false otherwise.
1048 jermar 1283
 */
3403 svoboda 1284
bool
1285
check_area_conflicts(as_t *as, uintptr_t va, size_t size, as_area_t *avoid_area)
1048 jermar 1286
{
1287
    as_area_t *a;
1147 jermar 1288
    btree_node_t *leaf, *node;
2745 decky 1289
    unsigned int i;
1048 jermar 1290
 
1070 jermar 1291
    /*
1292
     * We don't want any area to have conflicts with NULL page.
1293
     */
1294
    if (overlaps(va, size, NULL, PAGE_SIZE))
1295
        return false;
1296
 
1147 jermar 1297
    /*
1298
     * The leaf node is found in O(log n), where n is proportional to
1299
     * the number of address space areas belonging to as.
1300
     * The check for conflicts is then attempted on the rightmost
1150 jermar 1301
     * record in the left neighbour, the leftmost record in the right
1302
     * neighbour and all records in the leaf node itself.
1147 jermar 1303
     */
1048 jermar 1304
 
1147 jermar 1305
    if ((a = (as_area_t *) btree_search(&as->as_area_btree, va, &leaf))) {
1306
        if (a != avoid_area)
1307
            return false;
1308
    }
1309
 
1310
    /* First, check the two border cases. */
1150 jermar 1311
    if ((node = btree_leaf_node_left_neighbour(&as->as_area_btree, leaf))) {
1147 jermar 1312
        a = (as_area_t *) node->value[node->keys - 1];
1380 jermar 1313
        mutex_lock(&a->lock);
1147 jermar 1314
        if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
1380 jermar 1315
            mutex_unlock(&a->lock);
1147 jermar 1316
            return false;
1317
        }
1380 jermar 1318
        mutex_unlock(&a->lock);
1147 jermar 1319
    }
2087 jermar 1320
    node = btree_leaf_node_right_neighbour(&as->as_area_btree, leaf);
1321
    if (node) {
1147 jermar 1322
        a = (as_area_t *) node->value[0];
1380 jermar 1323
        mutex_lock(&a->lock);
1147 jermar 1324
        if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
1380 jermar 1325
            mutex_unlock(&a->lock);
1147 jermar 1326
            return false;
1327
        }
1380 jermar 1328
        mutex_unlock(&a->lock);
1147 jermar 1329
    }
1330
 
1331
    /* Second, check the leaf node. */
1332
    for (i = 0; i < leaf->keys; i++) {
1333
        a = (as_area_t *) leaf->value[i];
1334
 
1048 jermar 1335
        if (a == avoid_area)
1336
            continue;
1147 jermar 1337
 
1380 jermar 1338
        mutex_lock(&a->lock);
1147 jermar 1339
        if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
1380 jermar 1340
            mutex_unlock(&a->lock);
1147 jermar 1341
            return false;
1342
        }
1380 jermar 1343
        mutex_unlock(&a->lock);
1048 jermar 1344
    }
1345
 
1070 jermar 1346
    /*
1347
     * So far, the area does not conflict with other areas.
1348
     * Check if it doesn't conflict with kernel address space.
1349
     */  
1350
    if (!KERNEL_ADDRESS_SPACE_SHADOWED) {
1351
        return !overlaps(va, size,
2087 jermar 1352
            KERNEL_ADDRESS_SPACE_START,
1353
            KERNEL_ADDRESS_SPACE_END - KERNEL_ADDRESS_SPACE_START);
1070 jermar 1354
    }
1355
 
1048 jermar 1356
    return true;
1357
}
1235 jermar 1358
 
2556 jermar 1359
/** Return size of the address space area with given base.
1360
 *
1361
 * @param base      Arbitrary address insede the address space area.
1362
 *
1363
 * @return      Size of the address space area in bytes or zero if it
1364
 *          does not exist.
1365
 */
1366
size_t as_area_get_size(uintptr_t base)
1329 palkovsky 1367
{
1368
    ipl_t ipl;
1369
    as_area_t *src_area;
1370
    size_t size;
1371
 
1372
    ipl = interrupts_disable();
1373
    src_area = find_area_and_lock(AS, base);
3403 svoboda 1374
    if (src_area) {
1329 palkovsky 1375
        size = src_area->pages * PAGE_SIZE;
1380 jermar 1376
        mutex_unlock(&src_area->lock);
1329 palkovsky 1377
    } else {
1378
        size = 0;
1379
    }
1380
    interrupts_restore(ipl);
1381
    return size;
1382
}
1383
 
1387 jermar 1384
/** Mark portion of address space area as used.
1385
 *
1386
 * The address space area must be already locked.
1387
 *
3403 svoboda 1388
 * @param a     Address space area.
1389
 * @param page      First page to be marked.
1390
 * @param count     Number of page to be marked.
1387 jermar 1391
 *
3403 svoboda 1392
 * @return      Zero on failure and non-zero on success.
1387 jermar 1393
 */
1780 jermar 1394
int used_space_insert(as_area_t *a, uintptr_t page, count_t count)
1387 jermar 1395
{
1396
    btree_node_t *leaf, *node;
1397
    count_t pages;
2745 decky 1398
    unsigned int i;
1387 jermar 1399
 
1400
    ASSERT(page == ALIGN_DOWN(page, PAGE_SIZE));
1401
    ASSERT(count);
1402
 
1403
    pages = (count_t) btree_search(&a->used_space, page, &leaf);
1404
    if (pages) {
1405
        /*
1406
         * We hit the beginning of some used space.
1407
         */
1408
        return 0;
1409
    }
1410
 
1437 jermar 1411
    if (!leaf->keys) {
1412
        btree_insert(&a->used_space, page, (void *) count, leaf);
1413
        return 1;
1414
    }
1415
 
1387 jermar 1416
    node = btree_leaf_node_left_neighbour(&a->used_space, leaf);
1417
    if (node) {
2087 jermar 1418
        uintptr_t left_pg = node->key[node->keys - 1];
1419
        uintptr_t right_pg = leaf->key[0];
1420
        count_t left_cnt = (count_t) node->value[node->keys - 1];
1421
        count_t right_cnt = (count_t) leaf->value[0];
1387 jermar 1422
 
1423
        /*
1424
         * Examine the possibility that the interval fits
1425
         * somewhere between the rightmost interval of
1426
         * the left neigbour and the first interval of the leaf.
1427
         */
1428
 
1429
        if (page >= right_pg) {
1430
            /* Do nothing. */
2087 jermar 1431
        } else if (overlaps(page, count * PAGE_SIZE, left_pg,
1432
            left_cnt * PAGE_SIZE)) {
1387 jermar 1433
            /* The interval intersects with the left interval. */
1434
            return 0;
2087 jermar 1435
        } else if (overlaps(page, count * PAGE_SIZE, right_pg,
1436
            right_cnt * PAGE_SIZE)) {
1387 jermar 1437
            /* The interval intersects with the right interval. */
1438
            return 0;          
2087 jermar 1439
        } else if ((page == left_pg + left_cnt * PAGE_SIZE) &&
1440
            (page + count * PAGE_SIZE == right_pg)) {
1441
            /*
1442
             * The interval can be added by merging the two already
1443
             * present intervals.
1444
             */
1403 jermar 1445
            node->value[node->keys - 1] += count + right_cnt;
1387 jermar 1446
            btree_remove(&a->used_space, right_pg, leaf);
1447
            return 1;
2087 jermar 1448
        } else if (page == left_pg + left_cnt * PAGE_SIZE) {
1449
            /*
1450
             * The interval can be added by simply growing the left
1451
             * interval.
1452
             */
1403 jermar 1453
            node->value[node->keys - 1] += count;
1387 jermar 1454
            return 1;
2087 jermar 1455
        } else if (page + count * PAGE_SIZE == right_pg) {
1387 jermar 1456
            /*
2087 jermar 1457
             * The interval can be addded by simply moving base of
1458
             * the right interval down and increasing its size
1459
             * accordingly.
1387 jermar 1460
             */
1403 jermar 1461
            leaf->value[0] += count;
1387 jermar 1462
            leaf->key[0] = page;
1463
            return 1;
1464
        } else {
1465
            /*
1466
             * The interval is between both neigbouring intervals,
1467
             * but cannot be merged with any of them.
1468
             */
2087 jermar 1469
            btree_insert(&a->used_space, page, (void *) count,
1470
                leaf);
1387 jermar 1471
            return 1;
1472
        }
1473
    } else if (page < leaf->key[0]) {
1780 jermar 1474
        uintptr_t right_pg = leaf->key[0];
1387 jermar 1475
        count_t right_cnt = (count_t) leaf->value[0];
1476
 
1477
        /*
2087 jermar 1478
         * Investigate the border case in which the left neighbour does
1479
         * not exist but the interval fits from the left.
1387 jermar 1480
         */
1481
 
2087 jermar 1482
        if (overlaps(page, count * PAGE_SIZE, right_pg,
1483
            right_cnt * PAGE_SIZE)) {
1387 jermar 1484
            /* The interval intersects with the right interval. */
1485
            return 0;
2087 jermar 1486
        } else if (page + count * PAGE_SIZE == right_pg) {
1387 jermar 1487
            /*
2087 jermar 1488
             * The interval can be added by moving the base of the
1489
             * right interval down and increasing its size
1490
             * accordingly.
1387 jermar 1491
             */
1492
            leaf->key[0] = page;
1403 jermar 1493
            leaf->value[0] += count;
1387 jermar 1494
            return 1;
1495
        } else {
1496
            /*
1497
             * The interval doesn't adjoin with the right interval.
1498
             * It must be added individually.
1499
             */
2087 jermar 1500
            btree_insert(&a->used_space, page, (void *) count,
1501
                leaf);
1387 jermar 1502
            return 1;
1503
        }
1504
    }
1505
 
1506
    node = btree_leaf_node_right_neighbour(&a->used_space, leaf);
1507
    if (node) {
2087 jermar 1508
        uintptr_t left_pg = leaf->key[leaf->keys - 1];
1509
        uintptr_t right_pg = node->key[0];
1510
        count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
1511
        count_t right_cnt = (count_t) node->value[0];
1387 jermar 1512
 
1513
        /*
1514
         * Examine the possibility that the interval fits
1515
         * somewhere between the leftmost interval of
1516
         * the right neigbour and the last interval of the leaf.
1517
         */
1518
 
1519
        if (page < left_pg) {
1520
            /* Do nothing. */
2087 jermar 1521
        } else if (overlaps(page, count * PAGE_SIZE, left_pg,
1522
            left_cnt * PAGE_SIZE)) {
1387 jermar 1523
            /* The interval intersects with the left interval. */
1524
            return 0;
2087 jermar 1525
        } else if (overlaps(page, count * PAGE_SIZE, right_pg,
1526
            right_cnt * PAGE_SIZE)) {
1387 jermar 1527
            /* The interval intersects with the right interval. */
1528
            return 0;          
2087 jermar 1529
        } else if ((page == left_pg + left_cnt * PAGE_SIZE) &&
1530
            (page + count * PAGE_SIZE == right_pg)) {
1531
            /*
1532
             * The interval can be added by merging the two already
1533
             * present intervals.
1534
             * */
1403 jermar 1535
            leaf->value[leaf->keys - 1] += count + right_cnt;
1387 jermar 1536
            btree_remove(&a->used_space, right_pg, node);
1537
            return 1;
2087 jermar 1538
        } else if (page == left_pg + left_cnt * PAGE_SIZE) {
1539
            /*
1540
             * The interval can be added by simply growing the left
1541
             * interval.
1542
             * */
1403 jermar 1543
            leaf->value[leaf->keys - 1] +=  count;
1387 jermar 1544
            return 1;
2087 jermar 1545
        } else if (page + count * PAGE_SIZE == right_pg) {
1387 jermar 1546
            /*
2087 jermar 1547
             * The interval can be addded by simply moving base of
1548
             * the right interval down and increasing its size
1549
             * accordingly.
1387 jermar 1550
             */
1403 jermar 1551
            node->value[0] += count;
1387 jermar 1552
            node->key[0] = page;
1553
            return 1;
1554
        } else {
1555
            /*
1556
             * The interval is between both neigbouring intervals,
1557
             * but cannot be merged with any of them.
1558
             */
2087 jermar 1559
            btree_insert(&a->used_space, page, (void *) count,
1560
                leaf);
1387 jermar 1561
            return 1;
1562
        }
1563
    } else if (page >= leaf->key[leaf->keys - 1]) {
1780 jermar 1564
        uintptr_t left_pg = leaf->key[leaf->keys - 1];
1387 jermar 1565
        count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
1566
 
1567
        /*
2087 jermar 1568
         * Investigate the border case in which the right neighbour
1569
         * does not exist but the interval fits from the right.
1387 jermar 1570
         */
1571
 
2087 jermar 1572
        if (overlaps(page, count * PAGE_SIZE, left_pg,
1573
            left_cnt * PAGE_SIZE)) {
1403 jermar 1574
            /* The interval intersects with the left interval. */
1387 jermar 1575
            return 0;
2087 jermar 1576
        } else if (left_pg + left_cnt * PAGE_SIZE == page) {
1577
            /*
1578
             * The interval can be added by growing the left
1579
             * interval.
1580
             */
1403 jermar 1581
            leaf->value[leaf->keys - 1] += count;
1387 jermar 1582
            return 1;
1583
        } else {
1584
            /*
1585
             * The interval doesn't adjoin with the left interval.
1586
             * It must be added individually.
1587
             */
2087 jermar 1588
            btree_insert(&a->used_space, page, (void *) count,
1589
                leaf);
1387 jermar 1590
            return 1;
1591
        }
1592
    }
1593
 
1594
    /*
2087 jermar 1595
     * Note that if the algorithm made it thus far, the interval can fit
1596
     * only between two other intervals of the leaf. The two border cases
1597
     * were already resolved.
1387 jermar 1598
     */
1599
    for (i = 1; i < leaf->keys; i++) {
1600
        if (page < leaf->key[i]) {
2087 jermar 1601
            uintptr_t left_pg = leaf->key[i - 1];
1602
            uintptr_t right_pg = leaf->key[i];
1603
            count_t left_cnt = (count_t) leaf->value[i - 1];
1604
            count_t right_cnt = (count_t) leaf->value[i];
1387 jermar 1605
 
1606
            /*
1607
             * The interval fits between left_pg and right_pg.
1608
             */
1609
 
2087 jermar 1610
            if (overlaps(page, count * PAGE_SIZE, left_pg,
1611
                left_cnt * PAGE_SIZE)) {
1612
                /*
1613
                 * The interval intersects with the left
1614
                 * interval.
1615
                 */
1387 jermar 1616
                return 0;
2087 jermar 1617
            } else if (overlaps(page, count * PAGE_SIZE, right_pg,
1618
                right_cnt * PAGE_SIZE)) {
1619
                /*
1620
                 * The interval intersects with the right
1621
                 * interval.
1622
                 */
1387 jermar 1623
                return 0;          
2087 jermar 1624
            } else if ((page == left_pg + left_cnt * PAGE_SIZE) &&
1625
                (page + count * PAGE_SIZE == right_pg)) {
1626
                /*
1627
                 * The interval can be added by merging the two
1628
                 * already present intervals.
1629
                 */
1403 jermar 1630
                leaf->value[i - 1] += count + right_cnt;
1387 jermar 1631
                btree_remove(&a->used_space, right_pg, leaf);
1632
                return 1;
2087 jermar 1633
            } else if (page == left_pg + left_cnt * PAGE_SIZE) {
1634
                /*
1635
                 * The interval can be added by simply growing
1636
                 * the left interval.
1637
                 */
1403 jermar 1638
                leaf->value[i - 1] += count;
1387 jermar 1639
                return 1;
2087 jermar 1640
            } else if (page + count * PAGE_SIZE == right_pg) {
1387 jermar 1641
                /*
2087 jermar 1642
                     * The interval can be addded by simply moving
1643
                 * base of the right interval down and
1644
                 * increasing its size accordingly.
1387 jermar 1645
                 */
1403 jermar 1646
                leaf->value[i] += count;
1387 jermar 1647
                leaf->key[i] = page;
1648
                return 1;
1649
            } else {
1650
                /*
2087 jermar 1651
                 * The interval is between both neigbouring
1652
                 * intervals, but cannot be merged with any of
1653
                 * them.
1387 jermar 1654
                 */
2087 jermar 1655
                btree_insert(&a->used_space, page,
1656
                    (void *) count, leaf);
1387 jermar 1657
                return 1;
1658
            }
1659
        }
1660
    }
1661
 
3403 svoboda 1662
    panic("Inconsistency detected while adding %" PRIc " pages of used "
1663
        "space at %p.\n", count, page);
1387 jermar 1664
}
1665
 
1666
/** Mark portion of address space area as unused.
1667
 *
1668
 * The address space area must be already locked.
1669
 *
3403 svoboda 1670
 * @param a     Address space area.
1671
 * @param page      First page to be marked.
1672
 * @param count     Number of page to be marked.
1387 jermar 1673
 *
3403 svoboda 1674
 * @return      Zero on failure and non-zero on success.
1387 jermar 1675
 */
1780 jermar 1676
int used_space_remove(as_area_t *a, uintptr_t page, count_t count)
1387 jermar 1677
{
1678
    btree_node_t *leaf, *node;
1679
    count_t pages;
2745 decky 1680
    unsigned int i;
1387 jermar 1681
 
1682
    ASSERT(page == ALIGN_DOWN(page, PAGE_SIZE));
1683
    ASSERT(count);
1684
 
1685
    pages = (count_t) btree_search(&a->used_space, page, &leaf);
1686
    if (pages) {
1687
        /*
1688
         * We are lucky, page is the beginning of some interval.
1689
         */
1690
        if (count > pages) {
1691
            return 0;
1692
        } else if (count == pages) {
1693
            btree_remove(&a->used_space, page, leaf);
1403 jermar 1694
            return 1;
1387 jermar 1695
        } else {
1696
            /*
1697
             * Find the respective interval.
1698
             * Decrease its size and relocate its start address.
1699
             */
1700
            for (i = 0; i < leaf->keys; i++) {
1701
                if (leaf->key[i] == page) {
2087 jermar 1702
                    leaf->key[i] += count * PAGE_SIZE;
1403 jermar 1703
                    leaf->value[i] -= count;
1387 jermar 1704
                    return 1;
1705
                }
1706
            }
1707
            goto error;
1708
        }
1709
    }
1710
 
1711
    node = btree_leaf_node_left_neighbour(&a->used_space, leaf);
1712
    if (node && page < leaf->key[0]) {
1780 jermar 1713
        uintptr_t left_pg = node->key[node->keys - 1];
1387 jermar 1714
        count_t left_cnt = (count_t) node->value[node->keys - 1];
1715
 
2087 jermar 1716
        if (overlaps(left_pg, left_cnt * PAGE_SIZE, page,
1717
            count * PAGE_SIZE)) {
1718
            if (page + count * PAGE_SIZE ==
1719
                left_pg + left_cnt * PAGE_SIZE) {
1387 jermar 1720
                /*
2087 jermar 1721
                 * The interval is contained in the rightmost
1722
                 * interval of the left neighbour and can be
1723
                 * removed by updating the size of the bigger
1724
                 * interval.
1387 jermar 1725
                 */
1403 jermar 1726
                node->value[node->keys - 1] -= count;
1387 jermar 1727
                return 1;
2087 jermar 1728
            } else if (page + count * PAGE_SIZE <
1729
                left_pg + left_cnt*PAGE_SIZE) {
1403 jermar 1730
                count_t new_cnt;
1387 jermar 1731
 
1732
                /*
2087 jermar 1733
                 * The interval is contained in the rightmost
1734
                 * interval of the left neighbour but its
1735
                 * removal requires both updating the size of
1736
                 * the original interval and also inserting a
1737
                 * new interval.
1387 jermar 1738
                 */
2087 jermar 1739
                new_cnt = ((left_pg + left_cnt * PAGE_SIZE) -
1740
                    (page + count*PAGE_SIZE)) >> PAGE_WIDTH;
1403 jermar 1741
                node->value[node->keys - 1] -= count + new_cnt;
2087 jermar 1742
                btree_insert(&a->used_space, page +
1743
                    count * PAGE_SIZE, (void *) new_cnt, leaf);
1387 jermar 1744
                return 1;
1745
            }
1746
        }
1747
        return 0;
1748
    } else if (page < leaf->key[0]) {
1749
        return 0;
1750
    }
1751
 
1752
    if (page > leaf->key[leaf->keys - 1]) {
1780 jermar 1753
        uintptr_t left_pg = leaf->key[leaf->keys - 1];
1387 jermar 1754
        count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
1755
 
2087 jermar 1756
        if (overlaps(left_pg, left_cnt * PAGE_SIZE, page,
1757
            count * PAGE_SIZE)) {
1758
            if (page + count * PAGE_SIZE ==
1759
                left_pg + left_cnt * PAGE_SIZE) {
1387 jermar 1760
                /*
2087 jermar 1761
                 * The interval is contained in the rightmost
1762
                 * interval of the leaf and can be removed by
1763
                 * updating the size of the bigger interval.
1387 jermar 1764
                 */
1403 jermar 1765
                leaf->value[leaf->keys - 1] -= count;
1387 jermar 1766
                return 1;
2087 jermar 1767
            } else if (page + count * PAGE_SIZE < left_pg +
1768
                left_cnt * PAGE_SIZE) {
1403 jermar 1769
                count_t new_cnt;
1387 jermar 1770
 
1771
                /*
2087 jermar 1772
                 * The interval is contained in the rightmost
1773
                 * interval of the leaf but its removal
1774
                 * requires both updating the size of the
1775
                 * original interval and also inserting a new
1776
                 * interval.
1387 jermar 1777
                 */
2087 jermar 1778
                new_cnt = ((left_pg + left_cnt * PAGE_SIZE) -
1779
                    (page + count * PAGE_SIZE)) >> PAGE_WIDTH;
1403 jermar 1780
                leaf->value[leaf->keys - 1] -= count + new_cnt;
2087 jermar 1781
                btree_insert(&a->used_space, page +
1782
                    count * PAGE_SIZE, (void *) new_cnt, leaf);
1387 jermar 1783
                return 1;
1784
            }
1785
        }
1786
        return 0;
1787
    }  
1788
 
1789
    /*
1790
     * The border cases have been already resolved.
1791
     * Now the interval can be only between intervals of the leaf.
1792
     */
1793
    for (i = 1; i < leaf->keys - 1; i++) {
1794
        if (page < leaf->key[i]) {
1780 jermar 1795
            uintptr_t left_pg = leaf->key[i - 1];
1387 jermar 1796
            count_t left_cnt = (count_t) leaf->value[i - 1];
1797
 
1798
            /*
2087 jermar 1799
             * Now the interval is between intervals corresponding
1800
             * to (i - 1) and i.
1387 jermar 1801
             */
2087 jermar 1802
            if (overlaps(left_pg, left_cnt * PAGE_SIZE, page,
1803
                count * PAGE_SIZE)) {
1804
                if (page + count * PAGE_SIZE ==
1805
                    left_pg + left_cnt*PAGE_SIZE) {
1387 jermar 1806
                    /*
2087 jermar 1807
                     * The interval is contained in the
1808
                     * interval (i - 1) of the leaf and can
1809
                     * be removed by updating the size of
1810
                     * the bigger interval.
1387 jermar 1811
                     */
1403 jermar 1812
                    leaf->value[i - 1] -= count;
1387 jermar 1813
                    return 1;
2087 jermar 1814
                } else if (page + count * PAGE_SIZE <
1815
                    left_pg + left_cnt * PAGE_SIZE) {
1403 jermar 1816
                    count_t new_cnt;
1387 jermar 1817
 
1818
                    /*
2087 jermar 1819
                     * The interval is contained in the
1820
                     * interval (i - 1) of the leaf but its
1821
                     * removal requires both updating the
1822
                     * size of the original interval and
1387 jermar 1823
                     * also inserting a new interval.
1824
                     */
2087 jermar 1825
                    new_cnt = ((left_pg +
1826
                        left_cnt * PAGE_SIZE) -
1827
                        (page + count * PAGE_SIZE)) >>
1828
                        PAGE_WIDTH;
1403 jermar 1829
                    leaf->value[i - 1] -= count + new_cnt;
2087 jermar 1830
                    btree_insert(&a->used_space, page +
1831
                        count * PAGE_SIZE, (void *) new_cnt,
1832
                        leaf);
1387 jermar 1833
                    return 1;
1834
                }
1835
            }
1836
            return 0;
1837
        }
1838
    }
1839
 
1840
error:
3403 svoboda 1841
    panic("Inconsistency detected while removing %" PRIc " pages of used "
1842
        "space from %p.\n", count, page);
1387 jermar 1843
}
1844
 
1409 jermar 1845
/** Remove reference to address space area share info.
1846
 *
1847
 * If the reference count drops to 0, the sh_info is deallocated.
1848
 *
3403 svoboda 1849
 * @param sh_info   Pointer to address space area share info.
1409 jermar 1850
 */
1851
void sh_info_remove_reference(share_info_t *sh_info)
1852
{
1853
    bool dealloc = false;
1854
 
1855
    mutex_lock(&sh_info->lock);
1856
    ASSERT(sh_info->refcount);
1857
    if (--sh_info->refcount == 0) {
1858
        dealloc = true;
1495 jermar 1859
        link_t *cur;
1409 jermar 1860
 
1861
        /*
1862
         * Now walk carefully the pagemap B+tree and free/remove
1863
         * reference from all frames found there.
1864
         */
2087 jermar 1865
        for (cur = sh_info->pagemap.leaf_head.next;
1866
            cur != &sh_info->pagemap.leaf_head; cur = cur->next) {
1409 jermar 1867
            btree_node_t *node;
2745 decky 1868
            unsigned int i;
1409 jermar 1869
 
1495 jermar 1870
            node = list_get_instance(cur, btree_node_t, leaf_link);
1871
            for (i = 0; i < node->keys; i++)
1780 jermar 1872
                frame_free((uintptr_t) node->value[i]);
1409 jermar 1873
        }
1874
 
1875
    }
1876
    mutex_unlock(&sh_info->lock);
1877
 
1878
    if (dealloc) {
1879
        btree_destroy(&sh_info->pagemap);
1880
        free(sh_info);
1881
    }
1882
}
1883
 
1235 jermar 1884
/*
1885
 * Address space related syscalls.
1886
 */
1887
 
1888
/** Wrapper for as_area_create(). */
1780 jermar 1889
unative_t sys_as_area_create(uintptr_t address, size_t size, int flags)
1235 jermar 1890
{
2087 jermar 1891
    if (as_area_create(AS, flags | AS_AREA_CACHEABLE, size, address,
1892
        AS_AREA_ATTR_NONE, &anon_backend, NULL))
1780 jermar 1893
        return (unative_t) address;
1235 jermar 1894
    else
1780 jermar 1895
        return (unative_t) -1;
1235 jermar 1896
}
1897
 
1793 jermar 1898
/** Wrapper for as_area_resize(). */
1780 jermar 1899
unative_t sys_as_area_resize(uintptr_t address, size_t size, int flags)
1235 jermar 1900
{
1780 jermar 1901
    return (unative_t) as_area_resize(AS, address, size, 0);
1235 jermar 1902
}
1903
 
2984 svoboda 1904
/** Wrapper for as_area_change_flags(). */
1905
unative_t sys_as_area_change_flags(uintptr_t address, int flags)
1906
{
1907
    return (unative_t) as_area_change_flags(AS, flags, address);
1908
}
1909
 
1793 jermar 1910
/** Wrapper for as_area_destroy(). */
1780 jermar 1911
unative_t sys_as_area_destroy(uintptr_t address)
1306 jermar 1912
{
1780 jermar 1913
    return (unative_t) as_area_destroy(AS, address);
1306 jermar 1914
}
1702 cejka 1915
 
1914 jermar 1916
/** Print out information about address space.
1917
 *
3403 svoboda 1918
 * @param as        Address space.
1914 jermar 1919
 */
1920
void as_print(as_t *as)
1921
{
1922
    ipl_t ipl;
1923
 
1924
    ipl = interrupts_disable();
1925
    mutex_lock(&as->lock);
1926
 
1927
    /* print out info about address space areas */
1928
    link_t *cur;
2087 jermar 1929
    for (cur = as->as_area_btree.leaf_head.next;
1930
        cur != &as->as_area_btree.leaf_head; cur = cur->next) {
1931
        btree_node_t *node;
1914 jermar 1932
 
2087 jermar 1933
        node = list_get_instance(cur, btree_node_t, leaf_link);
1934
 
2745 decky 1935
        unsigned int i;
1914 jermar 1936
        for (i = 0; i < node->keys; i++) {
1915 jermar 1937
            as_area_t *area = node->value[i];
1914 jermar 1938
 
1939
            mutex_lock(&area->lock);
3403 svoboda 1940
            printf("as_area: %p, base=%p, pages=%" PRIc
1941
                " (%p - %p)\n", area, area->base, area->pages,
1942
                area->base, area->base + FRAMES2SIZE(area->pages));
1914 jermar 1943
            mutex_unlock(&area->lock);
1944
        }
1945
    }
1946
 
1947
    mutex_unlock(&as->lock);
1948
    interrupts_restore(ipl);
1949
}
1950
 
1757 jermar 1951
/** @}
1702 cejka 1952
 */