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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
 
2125 decky 85
#ifndef __OBJC__
1757 jermar 86
/**
87
 * Each architecture decides what functions will be used to carry out
88
 * address space operations such as creating or locking page tables.
89
 */
756 jermar 90
as_operations_t *as_operations = NULL;
703 jermar 91
 
1890 jermar 92
/**
93
 * Slab for as_t objects.
94
 */
95
static slab_cache_t *as_slab;
2126 decky 96
#endif
1890 jermar 97
 
2087 jermar 98
/**
2170 jermar 99
 * This lock serializes access to the ASID subsystem.
100
 * It protects:
101
 * - inactive_as_with_asid_head list
102
 * - as->asid for each as of the as_t type
103
 * - asids_allocated counter
2087 jermar 104
 */
2170 jermar 105
SPINLOCK_INITIALIZE(asidlock);
823 jermar 106
 
107
/**
108
 * This list contains address spaces that are not active on any
109
 * processor and that have valid ASID.
110
 */
111
LIST_INITIALIZE(inactive_as_with_asid_head);
112
 
757 jermar 113
/** Kernel address space. */
114
as_t *AS_KERNEL = NULL;
115
 
1235 jermar 116
static int area_flags_to_page_flags(int aflags);
1780 jermar 117
static as_area_t *find_area_and_lock(as_t *as, uintptr_t va);
2087 jermar 118
static bool check_area_conflicts(as_t *as, uintptr_t va, size_t size,
119
    as_area_t *avoid_area);
1409 jermar 120
static void sh_info_remove_reference(share_info_t *sh_info);
703 jermar 121
 
2126 decky 122
#ifndef __OBJC__
1891 jermar 123
static int as_constructor(void *obj, int flags)
124
{
125
    as_t *as = (as_t *) obj;
126
    int rc;
127
 
128
    link_initialize(&as->inactive_as_with_asid_link);
129
    mutex_initialize(&as->lock);   
130
 
131
    rc = as_constructor_arch(as, flags);
132
 
133
    return rc;
134
}
135
 
136
static int as_destructor(void *obj)
137
{
138
    as_t *as = (as_t *) obj;
139
 
140
    return as_destructor_arch(as);
141
}
2126 decky 142
#endif
1891 jermar 143
 
756 jermar 144
/** Initialize address space subsystem. */
145
void as_init(void)
146
{
147
    as_arch_init();
2126 decky 148
 
149
#ifndef __OBJC__
1891 jermar 150
    as_slab = slab_cache_create("as_slab", sizeof(as_t), 0,
2087 jermar 151
        as_constructor, as_destructor, SLAB_CACHE_MAGDEFERRED);
2126 decky 152
#endif
1890 jermar 153
 
789 palkovsky 154
    AS_KERNEL = as_create(FLAG_AS_KERNEL);
1383 decky 155
    if (!AS_KERNEL)
156
        panic("can't create kernel address space\n");
157
 
756 jermar 158
}
159
 
757 jermar 160
/** Create address space.
161
 *
162
 * @param flags Flags that influence way in wich the address space is created.
163
 */
756 jermar 164
as_t *as_create(int flags)
703 jermar 165
{
166
    as_t *as;
167
 
2126 decky 168
#ifdef __OBJC__
169
    as = [as_t new];
170
    link_initialize(&as->inactive_as_with_asid_link);
171
    mutex_initialize(&as->lock);   
172
    (void) as_constructor_arch(as, flags);
173
#else
1890 jermar 174
    as = (as_t *) slab_alloc(as_slab, 0);
2126 decky 175
#endif
1891 jermar 176
    (void) as_create_arch(as, 0);
177
 
1147 jermar 178
    btree_create(&as->as_area_btree);
822 palkovsky 179
 
180
    if (flags & FLAG_AS_KERNEL)
181
        as->asid = ASID_KERNEL;
182
    else
183
        as->asid = ASID_INVALID;
184
 
2183 jermar 185
    atomic_set(&as->refcount, 0);
1415 jermar 186
    as->cpu_refcount = 0;
2089 decky 187
#ifdef AS_PAGE_TABLE
2106 jermar 188
    as->genarch.page_table = page_table_create(flags);
2089 decky 189
#else
190
    page_table_create(flags);
191
#endif
703 jermar 192
 
193
    return as;
194
}
195
 
1468 jermar 196
/** Destroy adress space.
197
 *
2087 jermar 198
 * When there are no tasks referencing this address space (i.e. its refcount is
199
 * zero), the address space can be destroyed.
2183 jermar 200
 *
201
 * We know that we don't hold any spinlock.
1468 jermar 202
 */
203
void as_destroy(as_t *as)
973 palkovsky 204
{
1468 jermar 205
    ipl_t ipl;
1594 jermar 206
    bool cond;
2183 jermar 207
    DEADLOCK_PROBE_INIT(p_asidlock);
973 palkovsky 208
 
2183 jermar 209
    ASSERT(atomic_get(&as->refcount) == 0);
1468 jermar 210
 
211
    /*
212
     * Since there is no reference to this area,
213
     * it is safe not to lock its mutex.
214
     */
2170 jermar 215
 
2183 jermar 216
    /*
217
     * We need to avoid deadlock between TLB shootdown and asidlock.
218
     * We therefore try to take asid conditionally and if we don't succeed,
219
     * we enable interrupts and try again. This is done while preemption is
220
     * disabled to prevent nested context switches. We also depend on the
221
     * fact that so far no spinlocks are held.
222
     */
223
    preemption_disable();
224
    ipl = interrupts_read();
225
retry:
226
    interrupts_disable();
227
    if (!spinlock_trylock(&asidlock)) {
228
        interrupts_enable();
229
        DEADLOCK_PROBE(p_asidlock, DEADLOCK_THRESHOLD);
230
        goto retry;
231
    }
232
    preemption_enable();    /* Interrupts disabled, enable preemption */
1587 jermar 233
    if (as->asid != ASID_INVALID && as != AS_KERNEL) {
1594 jermar 234
        if (as != AS && as->cpu_refcount == 0)
1587 jermar 235
            list_remove(&as->inactive_as_with_asid_link);
1468 jermar 236
        asid_put(as->asid);
237
    }
2170 jermar 238
    spinlock_unlock(&asidlock);
1468 jermar 239
 
240
    /*
241
     * Destroy address space areas of the address space.
1954 jermar 242
     * The B+tree must be walked carefully because it is
1594 jermar 243
     * also being destroyed.
1468 jermar 244
     */
1594 jermar 245
    for (cond = true; cond; ) {
1468 jermar 246
        btree_node_t *node;
1594 jermar 247
 
248
        ASSERT(!list_empty(&as->as_area_btree.leaf_head));
2087 jermar 249
        node = list_get_instance(as->as_area_btree.leaf_head.next,
250
            btree_node_t, leaf_link);
1594 jermar 251
 
252
        if ((cond = node->keys)) {
253
            as_area_destroy(as, node->key[0]);
254
        }
1468 jermar 255
    }
1495 jermar 256
 
1483 jermar 257
    btree_destroy(&as->as_area_btree);
2089 decky 258
#ifdef AS_PAGE_TABLE
2106 jermar 259
    page_table_destroy(as->genarch.page_table);
2089 decky 260
#else
261
    page_table_destroy(NULL);
262
#endif
1468 jermar 263
 
264
    interrupts_restore(ipl);
2126 decky 265
 
266
#ifdef __OBJC__
267
    [as free];
268
#else
1890 jermar 269
    slab_free(as_slab, as);
2126 decky 270
#endif
973 palkovsky 271
}
272
 
703 jermar 273
/** Create address space area of common attributes.
274
 *
275
 * The created address space area is added to the target address space.
276
 *
277
 * @param as Target address space.
1239 jermar 278
 * @param flags Flags of the area memory.
1048 jermar 279
 * @param size Size of area.
703 jermar 280
 * @param base Base address of area.
1239 jermar 281
 * @param attrs Attributes of the area.
1409 jermar 282
 * @param backend Address space area backend. NULL if no backend is used.
283
 * @param backend_data NULL or a pointer to an array holding two void *.
703 jermar 284
 *
285
 * @return Address space area on success or NULL on failure.
286
 */
2069 jermar 287
as_area_t *
288
as_area_create(as_t *as, int flags, size_t size, uintptr_t base, int attrs,
1424 jermar 289
           mem_backend_t *backend, mem_backend_data_t *backend_data)
703 jermar 290
{
291
    ipl_t ipl;
292
    as_area_t *a;
293
 
294
    if (base % PAGE_SIZE)
1048 jermar 295
        return NULL;
296
 
1233 jermar 297
    if (!size)
298
        return NULL;
299
 
1048 jermar 300
    /* Writeable executable areas are not supported. */
301
    if ((flags & AS_AREA_EXEC) && (flags & AS_AREA_WRITE))
302
        return NULL;
703 jermar 303
 
304
    ipl = interrupts_disable();
1380 jermar 305
    mutex_lock(&as->lock);
703 jermar 306
 
1048 jermar 307
    if (!check_area_conflicts(as, base, size, NULL)) {
1380 jermar 308
        mutex_unlock(&as->lock);
1048 jermar 309
        interrupts_restore(ipl);
310
        return NULL;
311
    }
703 jermar 312
 
822 palkovsky 313
    a = (as_area_t *) malloc(sizeof(as_area_t), 0);
703 jermar 314
 
1380 jermar 315
    mutex_initialize(&a->lock);
822 palkovsky 316
 
1424 jermar 317
    a->as = as;
1026 jermar 318
    a->flags = flags;
1239 jermar 319
    a->attributes = attrs;
1048 jermar 320
    a->pages = SIZE2FRAMES(size);
822 palkovsky 321
    a->base = base;
1409 jermar 322
    a->sh_info = NULL;
323
    a->backend = backend;
1424 jermar 324
    if (backend_data)
325
        a->backend_data = *backend_data;
326
    else
2087 jermar 327
        memsetb((uintptr_t) &a->backend_data, sizeof(a->backend_data),
328
            0);
1424 jermar 329
 
1387 jermar 330
    btree_create(&a->used_space);
822 palkovsky 331
 
1147 jermar 332
    btree_insert(&as->as_area_btree, base, (void *) a, NULL);
822 palkovsky 333
 
1380 jermar 334
    mutex_unlock(&as->lock);
703 jermar 335
    interrupts_restore(ipl);
704 jermar 336
 
703 jermar 337
    return a;
338
}
339
 
1235 jermar 340
/** Find address space area and change it.
341
 *
342
 * @param as Address space.
2087 jermar 343
 * @param address Virtual address belonging to the area to be changed. Must be
344
 *     page-aligned.
1235 jermar 345
 * @param size New size of the virtual memory block starting at address.
346
 * @param flags Flags influencing the remap operation. Currently unused.
347
 *
1306 jermar 348
 * @return Zero on success or a value from @ref errno.h otherwise.
1235 jermar 349
 */
1780 jermar 350
int as_area_resize(as_t *as, uintptr_t address, size_t size, int flags)
1235 jermar 351
{
1306 jermar 352
    as_area_t *area;
1235 jermar 353
    ipl_t ipl;
354
    size_t pages;
355
 
356
    ipl = interrupts_disable();
1380 jermar 357
    mutex_lock(&as->lock);
1235 jermar 358
 
359
    /*
360
     * Locate the area.
361
     */
362
    area = find_area_and_lock(as, address);
363
    if (!area) {
1380 jermar 364
        mutex_unlock(&as->lock);
1235 jermar 365
        interrupts_restore(ipl);
1306 jermar 366
        return ENOENT;
1235 jermar 367
    }
368
 
1424 jermar 369
    if (area->backend == &phys_backend) {
1235 jermar 370
        /*
371
         * Remapping of address space areas associated
372
         * with memory mapped devices is not supported.
373
         */
1380 jermar 374
        mutex_unlock(&area->lock);
375
        mutex_unlock(&as->lock);
1235 jermar 376
        interrupts_restore(ipl);
1306 jermar 377
        return ENOTSUP;
1235 jermar 378
    }
1409 jermar 379
    if (area->sh_info) {
380
        /*
381
         * Remapping of shared address space areas
382
         * is not supported.
383
         */
384
        mutex_unlock(&area->lock);
385
        mutex_unlock(&as->lock);
386
        interrupts_restore(ipl);
387
        return ENOTSUP;
388
    }
1235 jermar 389
 
390
    pages = SIZE2FRAMES((address - area->base) + size);
391
    if (!pages) {
392
        /*
393
         * Zero size address space areas are not allowed.
394
         */
1380 jermar 395
        mutex_unlock(&area->lock);
396
        mutex_unlock(&as->lock);
1235 jermar 397
        interrupts_restore(ipl);
1306 jermar 398
        return EPERM;
1235 jermar 399
    }
400
 
401
    if (pages < area->pages) {
1403 jermar 402
        bool cond;
1780 jermar 403
        uintptr_t start_free = area->base + pages*PAGE_SIZE;
1235 jermar 404
 
405
        /*
406
         * Shrinking the area.
407
         * No need to check for overlaps.
408
         */
1403 jermar 409
 
410
        /*
1436 jermar 411
         * Start TLB shootdown sequence.
412
         */
2087 jermar 413
        tlb_shootdown_start(TLB_INVL_PAGES, AS->asid, area->base +
414
            pages * PAGE_SIZE, area->pages - pages);
1436 jermar 415
 
416
        /*
1403 jermar 417
         * Remove frames belonging to used space starting from
418
         * the highest addresses downwards until an overlap with
419
         * the resized address space area is found. Note that this
420
         * is also the right way to remove part of the used_space
421
         * B+tree leaf list.
422
         */    
423
        for (cond = true; cond;) {
424
            btree_node_t *node;
425
 
426
            ASSERT(!list_empty(&area->used_space.leaf_head));
2087 jermar 427
            node =
428
                list_get_instance(area->used_space.leaf_head.prev,
429
                btree_node_t, leaf_link);
1403 jermar 430
            if ((cond = (bool) node->keys)) {
1780 jermar 431
                uintptr_t b = node->key[node->keys - 1];
2087 jermar 432
                count_t c =
433
                    (count_t) node->value[node->keys - 1];
2745 decky 434
                unsigned int i = 0;
1235 jermar 435
 
2087 jermar 436
                if (overlaps(b, c * PAGE_SIZE, area->base,
2133 jermar 437
                    pages * PAGE_SIZE)) {
1403 jermar 438
 
2087 jermar 439
                    if (b + c * PAGE_SIZE <= start_free) {
1403 jermar 440
                        /*
2087 jermar 441
                         * The whole interval fits
442
                         * completely in the resized
443
                         * address space area.
1403 jermar 444
                         */
445
                        break;
446
                    }
447
 
448
                    /*
2087 jermar 449
                     * Part of the interval corresponding
450
                     * to b and c overlaps with the resized
451
                     * address space area.
1403 jermar 452
                     */
453
 
454
                    cond = false;   /* we are almost done */
455
                    i = (start_free - b) >> PAGE_WIDTH;
2087 jermar 456
                    if (!used_space_remove(area, start_free,
457
                        c - i))
458
                        panic("Could not remove used "
459
                            "space.\n");
1403 jermar 460
                } else {
461
                    /*
2087 jermar 462
                     * The interval of used space can be
463
                     * completely removed.
1403 jermar 464
                     */
465
                    if (!used_space_remove(area, b, c))
2087 jermar 466
                        panic("Could not remove used "
467
                            "space.\n");
1403 jermar 468
                }
469
 
470
                for (; i < c; i++) {
471
                    pte_t *pte;
472
 
473
                    page_table_lock(as, false);
2087 jermar 474
                    pte = page_mapping_find(as, b +
475
                        i * PAGE_SIZE);
476
                    ASSERT(pte && PTE_VALID(pte) &&
477
                        PTE_PRESENT(pte));
478
                    if (area->backend &&
479
                        area->backend->frame_free) {
1424 jermar 480
                        area->backend->frame_free(area,
2087 jermar 481
                            b + i * PAGE_SIZE,
482
                            PTE_GET_FRAME(pte));
1409 jermar 483
                    }
2087 jermar 484
                    page_mapping_remove(as, b +
485
                        i * PAGE_SIZE);
1403 jermar 486
                    page_table_unlock(as, false);
487
                }
1235 jermar 488
            }
489
        }
1436 jermar 490
 
1235 jermar 491
        /*
1436 jermar 492
         * Finish TLB shootdown sequence.
1235 jermar 493
         */
2183 jermar 494
 
2087 jermar 495
        tlb_invalidate_pages(as->asid, area->base + pages * PAGE_SIZE,
496
            area->pages - pages);
1889 jermar 497
        /*
498
         * Invalidate software translation caches (e.g. TSB on sparc64).
499
         */
2087 jermar 500
        as_invalidate_translation_cache(as, area->base +
501
            pages * PAGE_SIZE, area->pages - pages);
2183 jermar 502
        tlb_shootdown_finalize();
503
 
1235 jermar 504
    } else {
505
        /*
506
         * Growing the area.
507
         * Check for overlaps with other address space areas.
508
         */
2087 jermar 509
        if (!check_area_conflicts(as, address, pages * PAGE_SIZE,
510
            area)) {
1380 jermar 511
            mutex_unlock(&area->lock);
512
            mutex_unlock(&as->lock);       
1235 jermar 513
            interrupts_restore(ipl);
1306 jermar 514
            return EADDRNOTAVAIL;
1235 jermar 515
        }
516
    }
517
 
518
    area->pages = pages;
519
 
1380 jermar 520
    mutex_unlock(&area->lock);
521
    mutex_unlock(&as->lock);
1235 jermar 522
    interrupts_restore(ipl);
523
 
1306 jermar 524
    return 0;
1235 jermar 525
}
526
 
1306 jermar 527
/** Destroy address space area.
528
 *
529
 * @param as Address space.
530
 * @param address Address withing the area to be deleted.
531
 *
532
 * @return Zero on success or a value from @ref errno.h on failure.
533
 */
1780 jermar 534
int as_area_destroy(as_t *as, uintptr_t address)
1306 jermar 535
{
536
    as_area_t *area;
1780 jermar 537
    uintptr_t base;
1495 jermar 538
    link_t *cur;
1306 jermar 539
    ipl_t ipl;
540
 
541
    ipl = interrupts_disable();
1380 jermar 542
    mutex_lock(&as->lock);
1306 jermar 543
 
544
    area = find_area_and_lock(as, address);
545
    if (!area) {
1380 jermar 546
        mutex_unlock(&as->lock);
1306 jermar 547
        interrupts_restore(ipl);
548
        return ENOENT;
549
    }
550
 
1403 jermar 551
    base = area->base;
552
 
1411 jermar 553
    /*
1436 jermar 554
     * Start TLB shootdown sequence.
555
     */
1889 jermar 556
    tlb_shootdown_start(TLB_INVL_PAGES, as->asid, area->base, area->pages);
1436 jermar 557
 
558
    /*
1411 jermar 559
     * Visit only the pages mapped by used_space B+tree.
560
     */
2087 jermar 561
    for (cur = area->used_space.leaf_head.next;
562
        cur != &area->used_space.leaf_head; cur = cur->next) {
1411 jermar 563
        btree_node_t *node;
2745 decky 564
        unsigned int i;
1403 jermar 565
 
1495 jermar 566
        node = list_get_instance(cur, btree_node_t, leaf_link);
567
        for (i = 0; i < node->keys; i++) {
1780 jermar 568
            uintptr_t b = node->key[i];
1495 jermar 569
            count_t j;
1411 jermar 570
            pte_t *pte;
1403 jermar 571
 
1495 jermar 572
            for (j = 0; j < (count_t) node->value[i]; j++) {
1411 jermar 573
                page_table_lock(as, false);
2087 jermar 574
                pte = page_mapping_find(as, b + j * PAGE_SIZE);
575
                ASSERT(pte && PTE_VALID(pte) &&
576
                    PTE_PRESENT(pte));
577
                if (area->backend &&
578
                    area->backend->frame_free) {
579
                    area->backend->frame_free(area, b +
2133 jermar 580
                        j * PAGE_SIZE, PTE_GET_FRAME(pte));
1403 jermar 581
                }
2087 jermar 582
                page_mapping_remove(as, b + j * PAGE_SIZE);            
1411 jermar 583
                page_table_unlock(as, false);
1306 jermar 584
            }
585
        }
586
    }
1403 jermar 587
 
1306 jermar 588
    /*
1436 jermar 589
     * Finish TLB shootdown sequence.
1306 jermar 590
     */
2183 jermar 591
 
1889 jermar 592
    tlb_invalidate_pages(as->asid, area->base, area->pages);
593
    /*
2087 jermar 594
     * Invalidate potential software translation caches (e.g. TSB on
595
     * sparc64).
1889 jermar 596
     */
597
    as_invalidate_translation_cache(as, area->base, area->pages);
2183 jermar 598
    tlb_shootdown_finalize();
1889 jermar 599
 
1436 jermar 600
    btree_destroy(&area->used_space);
1306 jermar 601
 
1309 jermar 602
    area->attributes |= AS_AREA_ATTR_PARTIAL;
1409 jermar 603
 
604
    if (area->sh_info)
605
        sh_info_remove_reference(area->sh_info);
606
 
1380 jermar 607
    mutex_unlock(&area->lock);
1306 jermar 608
 
609
    /*
610
     * Remove the empty area from address space.
611
     */
1889 jermar 612
    btree_remove(&as->as_area_btree, base, NULL);
1306 jermar 613
 
1309 jermar 614
    free(area);
615
 
1889 jermar 616
    mutex_unlock(&as->lock);
1306 jermar 617
    interrupts_restore(ipl);
618
    return 0;
619
}
620
 
1413 jermar 621
/** Share address space area with another or the same address space.
1235 jermar 622
 *
1424 jermar 623
 * Address space area mapping is shared with a new address space area.
624
 * If the source address space area has not been shared so far,
625
 * a new sh_info is created. The new address space area simply gets the
626
 * sh_info of the source area. The process of duplicating the
627
 * mapping is done through the backend share function.
1413 jermar 628
 *
1417 jermar 629
 * @param src_as Pointer to source address space.
1239 jermar 630
 * @param src_base Base address of the source address space area.
1417 jermar 631
 * @param acc_size Expected size of the source area.
1428 palkovsky 632
 * @param dst_as Pointer to destination address space.
1417 jermar 633
 * @param dst_base Target base address.
634
 * @param dst_flags_mask Destination address space area flags mask.
1235 jermar 635
 *
2007 jermar 636
 * @return Zero on success or ENOENT if there is no such task or if there is no
637
 * such address space area, EPERM if there was a problem in accepting the area
638
 * or ENOMEM if there was a problem in allocating destination address space
639
 * area. ENOTSUP is returned if the address space area backend does not support
2141 jermar 640
 * sharing.
1235 jermar 641
 */
1780 jermar 642
int as_area_share(as_t *src_as, uintptr_t src_base, size_t acc_size,
2647 jermar 643
    as_t *dst_as, uintptr_t dst_base, int dst_flags_mask)
1235 jermar 644
{
645
    ipl_t ipl;
1239 jermar 646
    int src_flags;
647
    size_t src_size;
648
    as_area_t *src_area, *dst_area;
1413 jermar 649
    share_info_t *sh_info;
1424 jermar 650
    mem_backend_t *src_backend;
651
    mem_backend_data_t src_backend_data;
1434 palkovsky 652
 
1235 jermar 653
    ipl = interrupts_disable();
1380 jermar 654
    mutex_lock(&src_as->lock);
1329 palkovsky 655
    src_area = find_area_and_lock(src_as, src_base);
1239 jermar 656
    if (!src_area) {
1238 jermar 657
        /*
658
         * Could not find the source address space area.
659
         */
1380 jermar 660
        mutex_unlock(&src_as->lock);
1238 jermar 661
        interrupts_restore(ipl);
662
        return ENOENT;
663
    }
2007 jermar 664
 
1424 jermar 665
    if (!src_area->backend || !src_area->backend->share) {
1413 jermar 666
        /*
1851 jermar 667
         * There is no backend or the backend does not
1424 jermar 668
         * know how to share the area.
1413 jermar 669
         */
670
        mutex_unlock(&src_area->lock);
671
        mutex_unlock(&src_as->lock);
672
        interrupts_restore(ipl);
673
        return ENOTSUP;
674
    }
675
 
1239 jermar 676
    src_size = src_area->pages * PAGE_SIZE;
677
    src_flags = src_area->flags;
1424 jermar 678
    src_backend = src_area->backend;
679
    src_backend_data = src_area->backend_data;
1544 palkovsky 680
 
681
    /* Share the cacheable flag from the original mapping */
682
    if (src_flags & AS_AREA_CACHEABLE)
683
        dst_flags_mask |= AS_AREA_CACHEABLE;
684
 
2087 jermar 685
    if (src_size != acc_size ||
686
        (src_flags & dst_flags_mask) != dst_flags_mask) {
1413 jermar 687
        mutex_unlock(&src_area->lock);
688
        mutex_unlock(&src_as->lock);
1235 jermar 689
        interrupts_restore(ipl);
690
        return EPERM;
691
    }
1413 jermar 692
 
1235 jermar 693
    /*
1413 jermar 694
     * Now we are committed to sharing the area.
1954 jermar 695
     * First, prepare the area for sharing.
1413 jermar 696
     * Then it will be safe to unlock it.
697
     */
698
    sh_info = src_area->sh_info;
699
    if (!sh_info) {
700
        sh_info = (share_info_t *) malloc(sizeof(share_info_t), 0);
701
        mutex_initialize(&sh_info->lock);
702
        sh_info->refcount = 2;
703
        btree_create(&sh_info->pagemap);
704
        src_area->sh_info = sh_info;
2647 jermar 705
        /*
706
         * Call the backend to setup sharing.
707
         */
708
        src_area->backend->share(src_area);
1413 jermar 709
    } else {
710
        mutex_lock(&sh_info->lock);
711
        sh_info->refcount++;
712
        mutex_unlock(&sh_info->lock);
713
    }
714
 
715
    mutex_unlock(&src_area->lock);
716
    mutex_unlock(&src_as->lock);
717
 
718
    /*
1239 jermar 719
     * Create copy of the source address space area.
720
     * The destination area is created with AS_AREA_ATTR_PARTIAL
721
     * attribute set which prevents race condition with
722
     * preliminary as_page_fault() calls.
1417 jermar 723
     * The flags of the source area are masked against dst_flags_mask
724
     * to support sharing in less privileged mode.
1235 jermar 725
     */
1461 palkovsky 726
    dst_area = as_area_create(dst_as, dst_flags_mask, src_size, dst_base,
2087 jermar 727
        AS_AREA_ATTR_PARTIAL, src_backend, &src_backend_data);
1239 jermar 728
    if (!dst_area) {
1235 jermar 729
        /*
730
         * Destination address space area could not be created.
731
         */
1413 jermar 732
        sh_info_remove_reference(sh_info);
733
 
1235 jermar 734
        interrupts_restore(ipl);
735
        return ENOMEM;
736
    }
2009 jermar 737
 
1235 jermar 738
    /*
1239 jermar 739
     * Now the destination address space area has been
740
     * fully initialized. Clear the AS_AREA_ATTR_PARTIAL
1413 jermar 741
     * attribute and set the sh_info.
1239 jermar 742
     */
2009 jermar 743
    mutex_lock(&dst_as->lock); 
1380 jermar 744
    mutex_lock(&dst_area->lock);
1239 jermar 745
    dst_area->attributes &= ~AS_AREA_ATTR_PARTIAL;
1413 jermar 746
    dst_area->sh_info = sh_info;
1380 jermar 747
    mutex_unlock(&dst_area->lock);
2009 jermar 748
    mutex_unlock(&dst_as->lock);   
749
 
1235 jermar 750
    interrupts_restore(ipl);
751
 
752
    return 0;
753
}
754
 
1423 jermar 755
/** Check access mode for address space area.
756
 *
757
 * The address space area must be locked prior to this call.
758
 *
759
 * @param area Address space area.
760
 * @param access Access mode.
761
 *
762
 * @return False if access violates area's permissions, true otherwise.
763
 */
764
bool as_area_check_access(as_area_t *area, pf_access_t access)
765
{
766
    int flagmap[] = {
767
        [PF_ACCESS_READ] = AS_AREA_READ,
768
        [PF_ACCESS_WRITE] = AS_AREA_WRITE,
769
        [PF_ACCESS_EXEC] = AS_AREA_EXEC
770
    };
771
 
772
    if (!(area->flags & flagmap[access]))
773
        return false;
774
 
775
    return true;
776
}
777
 
703 jermar 778
/** Handle page fault within the current address space.
779
 *
1409 jermar 780
 * This is the high-level page fault handler. It decides
781
 * whether the page fault can be resolved by any backend
782
 * and if so, it invokes the backend to resolve the page
783
 * fault.
784
 *
703 jermar 785
 * Interrupts are assumed disabled.
786
 *
787
 * @param page Faulting page.
1411 jermar 788
 * @param access Access mode that caused the fault (i.e. read/write/exec).
1288 jermar 789
 * @param istate Pointer to interrupted state.
703 jermar 790
 *
1409 jermar 791
 * @return AS_PF_FAULT on page fault, AS_PF_OK on success or AS_PF_DEFER if the
792
 *     fault was caused by copy_to_uspace() or copy_from_uspace().
703 jermar 793
 */
1780 jermar 794
int as_page_fault(uintptr_t page, pf_access_t access, istate_t *istate)
703 jermar 795
{
1044 jermar 796
    pte_t *pte;
977 jermar 797
    as_area_t *area;
703 jermar 798
 
1380 jermar 799
    if (!THREAD)
1409 jermar 800
        return AS_PF_FAULT;
1380 jermar 801
 
703 jermar 802
    ASSERT(AS);
1044 jermar 803
 
1380 jermar 804
    mutex_lock(&AS->lock);
977 jermar 805
    area = find_area_and_lock(AS, page);   
703 jermar 806
    if (!area) {
807
        /*
808
         * No area contained mapping for 'page'.
809
         * Signal page fault to low-level handler.
810
         */
1380 jermar 811
        mutex_unlock(&AS->lock);
1288 jermar 812
        goto page_fault;
703 jermar 813
    }
814
 
1239 jermar 815
    if (area->attributes & AS_AREA_ATTR_PARTIAL) {
816
        /*
817
         * The address space area is not fully initialized.
818
         * Avoid possible race by returning error.
819
         */
1380 jermar 820
        mutex_unlock(&area->lock);
821
        mutex_unlock(&AS->lock);
1288 jermar 822
        goto page_fault;       
1239 jermar 823
    }
824
 
1424 jermar 825
    if (!area->backend || !area->backend->page_fault) {
1409 jermar 826
        /*
827
         * The address space area is not backed by any backend
828
         * or the backend cannot handle page faults.
829
         */
830
        mutex_unlock(&area->lock);
831
        mutex_unlock(&AS->lock);
832
        goto page_fault;       
833
    }
1179 jermar 834
 
1044 jermar 835
    page_table_lock(AS, false);
836
 
703 jermar 837
    /*
1044 jermar 838
     * To avoid race condition between two page faults
839
     * on the same address, we need to make sure
840
     * the mapping has not been already inserted.
841
     */
842
    if ((pte = page_mapping_find(AS, page))) {
843
        if (PTE_PRESENT(pte)) {
1423 jermar 844
            if (((access == PF_ACCESS_READ) && PTE_READABLE(pte)) ||
2087 jermar 845
                (access == PF_ACCESS_WRITE && PTE_WRITABLE(pte)) ||
846
                (access == PF_ACCESS_EXEC && PTE_EXECUTABLE(pte))) {
1423 jermar 847
                page_table_unlock(AS, false);
848
                mutex_unlock(&area->lock);
849
                mutex_unlock(&AS->lock);
850
                return AS_PF_OK;
851
            }
1044 jermar 852
        }
853
    }
1409 jermar 854
 
1044 jermar 855
    /*
1409 jermar 856
     * Resort to the backend page fault handler.
703 jermar 857
     */
1424 jermar 858
    if (area->backend->page_fault(area, page, access) != AS_PF_OK) {
1409 jermar 859
        page_table_unlock(AS, false);
860
        mutex_unlock(&area->lock);
861
        mutex_unlock(&AS->lock);
862
        goto page_fault;
863
    }
703 jermar 864
 
1044 jermar 865
    page_table_unlock(AS, false);
1380 jermar 866
    mutex_unlock(&area->lock);
867
    mutex_unlock(&AS->lock);
1288 jermar 868
    return AS_PF_OK;
869
 
870
page_fault:
871
    if (THREAD->in_copy_from_uspace) {
872
        THREAD->in_copy_from_uspace = false;
2087 jermar 873
        istate_set_retaddr(istate,
874
            (uintptr_t) &memcpy_from_uspace_failover_address);
1288 jermar 875
    } else if (THREAD->in_copy_to_uspace) {
876
        THREAD->in_copy_to_uspace = false;
2087 jermar 877
        istate_set_retaddr(istate,
878
            (uintptr_t) &memcpy_to_uspace_failover_address);
1288 jermar 879
    } else {
880
        return AS_PF_FAULT;
881
    }
882
 
883
    return AS_PF_DEFER;
703 jermar 884
}
885
 
823 jermar 886
/** Switch address spaces.
703 jermar 887
 *
1380 jermar 888
 * Note that this function cannot sleep as it is essentially a part of
2170 jermar 889
 * scheduling. Sleeping here would lead to deadlock on wakeup. Another
890
 * thing which is forbidden in this context is locking the address space.
1380 jermar 891
 *
2183 jermar 892
 * When this function is enetered, no spinlocks may be held.
893
 *
823 jermar 894
 * @param old Old address space or NULL.
895
 * @param new New address space.
703 jermar 896
 */
2106 jermar 897
void as_switch(as_t *old_as, as_t *new_as)
703 jermar 898
{
2183 jermar 899
    DEADLOCK_PROBE_INIT(p_asidlock);
900
    preemption_disable();
901
retry:
902
    (void) interrupts_disable();
903
    if (!spinlock_trylock(&asidlock)) {
904
        /*
905
         * Avoid deadlock with TLB shootdown.
906
         * We can enable interrupts here because
907
         * preemption is disabled. We should not be
908
         * holding any other lock.
909
         */
910
        (void) interrupts_enable();
911
        DEADLOCK_PROBE(p_asidlock, DEADLOCK_THRESHOLD);
912
        goto retry;
913
    }
914
    preemption_enable();
703 jermar 915
 
916
    /*
823 jermar 917
     * First, take care of the old address space.
918
     */
2106 jermar 919
    if (old_as) {
920
        ASSERT(old_as->cpu_refcount);
921
        if((--old_as->cpu_refcount == 0) && (old_as != AS_KERNEL)) {
823 jermar 922
            /*
923
             * The old address space is no longer active on
924
             * any processor. It can be appended to the
925
             * list of inactive address spaces with assigned
926
             * ASID.
927
             */
2141 jermar 928
            ASSERT(old_as->asid != ASID_INVALID);
929
            list_append(&old_as->inactive_as_with_asid_link,
930
                &inactive_as_with_asid_head);
823 jermar 931
        }
1890 jermar 932
 
933
        /*
934
         * Perform architecture-specific tasks when the address space
935
         * is being removed from the CPU.
936
         */
2106 jermar 937
        as_deinstall_arch(old_as);
823 jermar 938
    }
939
 
940
    /*
941
     * Second, prepare the new address space.
942
     */
2106 jermar 943
    if ((new_as->cpu_refcount++ == 0) && (new_as != AS_KERNEL)) {
2170 jermar 944
        if (new_as->asid != ASID_INVALID)
2106 jermar 945
            list_remove(&new_as->inactive_as_with_asid_link);
2170 jermar 946
        else
947
            new_as->asid = asid_get();
823 jermar 948
    }
2106 jermar 949
#ifdef AS_PAGE_TABLE
950
    SET_PTL0_ADDRESS(new_as->genarch.page_table);
951
#endif
823 jermar 952
 
953
    /*
703 jermar 954
     * Perform architecture-specific steps.
727 jermar 955
     * (e.g. write ASID to hardware register etc.)
703 jermar 956
     */
2106 jermar 957
    as_install_arch(new_as);
2170 jermar 958
 
959
    spinlock_unlock(&asidlock);
703 jermar 960
 
2106 jermar 961
    AS = new_as;
703 jermar 962
}
754 jermar 963
 
3013 svoboda 964
/** Write directly into a page, bypassing area flags.
965
 *
966
 * This allows a debugger to write into a page that is mapped read-only
967
 * (such as the text segment). Naturally, this is only possible if the
968
 * correspoinding area is not shared and anonymous.
969
 *
970
 * FIXME: doesn't take into account that it isn't a good idea to write
971
 * into the frame if the area is shared or isn't anonymous
972
 */
973
static int debug_write_inside_page(uintptr_t va, void *data, size_t n)
974
{
975
    uintptr_t page;
976
    pte_t *pte;
977
    as_area_t *area;
978
    uintptr_t frame;
979
    ipl_t ipl;
980
    int rc;
981
 
982
    page = ALIGN_DOWN(va, PAGE_SIZE);
983
    ASSERT(ALIGN_DOWN(va + n - 1, PAGE_SIZE) == page);
984
 
985
restart:
986
    mutex_lock(&AS->lock);
987
    ipl = interrupts_disable();
988
    area = find_area_and_lock(AS, page);
3036 svoboda 989
    if (area->backend != &anon_backend || area->sh_info != NULL) {
990
        mutex_unlock(&area->lock);
991
        mutex_unlock(&AS->lock);
992
        interrupts_restore(ipl);
3013 svoboda 993
 
3036 svoboda 994
        rc = as_area_make_writeable(area->base);
995
        if (rc != 0) return rc;
996
 
997
        goto restart;
998
    }
999
 
3013 svoboda 1000
    pte = page_mapping_find(AS, page);
1001
    if (! (pte && PTE_VALID(pte) && PTE_PRESENT(pte)) ) {
1002
        mutex_unlock(&area->lock);
1003
        mutex_unlock(&AS->lock);
1004
        interrupts_restore(ipl);
1005
 
1006
        rc = as_page_fault(page, PF_ACCESS_WRITE, NULL);
1007
        if (rc == AS_PF_FAULT) return EINVAL;
1008
 
1009
        goto restart;
1010
    }
1011
 
1012
    frame = PTE_GET_FRAME(pte);
1013
    memcpy((void *)(PA2KA(frame) + (va - page)), data, n);
1014
 
1015
    mutex_unlock(&area->lock);
1016
    mutex_unlock(&AS->lock);
1017
    interrupts_restore(ipl);
1018
 
1019
    return EOK;
1020
}
1021
 
1022
/** Write data bypassing area flags.
1023
 *
1024
 * See debug_write_inside_page().
1025
 */
1026
int as_debug_write(uintptr_t va, void *data, size_t n)
1027
{
1028
    size_t now;
1029
    int rc;
1030
 
1031
    while (n > 0) {
3127 svoboda 1032
        /* Number of bytes until the end of page */
1033
        now = ALIGN_DOWN(va, PAGE_SIZE) + PAGE_SIZE - va;
3013 svoboda 1034
        if (now > n) now = n;
1035
 
1036
        rc = debug_write_inside_page(va, data, now);
1037
        if (rc != EOK) return rc;
1038
 
1039
        va += now;
1040
        data += now;
1041
        n -= now;
1042
    }
1043
 
1044
    return EOK;
1045
}
1046
 
3036 svoboda 1047
/** Make sure area is private and anonymous.
1048
 *
1049
 * Not atomic atm.
1050
 * @param address   Virtual address in AS.
1051
 */
1052
int as_area_make_writeable(uintptr_t address)
1053
{
1054
    ipl_t ipl;
1055
    as_area_t *area;
1056
    uintptr_t base, page;
1057
    uintptr_t old_frame, frame;
1058
    size_t size;
1059
    int flags;
1060
    int page_flags;
1061
    pte_t *pte;
1062
    int rc;
1063
    uintptr_t *pagemap;
1064
 
1065
    ipl = interrupts_disable();
1066
    mutex_lock(&AS->lock);
1067
    area = find_area_and_lock(AS, address);
1068
    if (!area) {
1069
        /*
1070
         * Could not find the address space area.
1071
         */
1072
        mutex_unlock(&AS->lock);
1073
        interrupts_restore(ipl);
1074
        return ENOENT;
1075
    }
1076
 
1077
    if (area->backend == &anon_backend && !area->sh_info) {
1078
        /* Nothing to do */
1079
        mutex_unlock(&area->lock);
1080
        mutex_unlock(&AS->lock);
1081
        interrupts_restore(ipl);
1082
        return EOK;
1083
    }
1084
 
1085
    base = area->base;
1086
    size = area->pages * PAGE_SIZE;
1087
    flags = area->flags;
1088
    page_flags = as_area_get_flags(area);
1089
 
1090
    pagemap = malloc(area->pages * sizeof(uintptr_t), 0);
1091
    page_table_lock(AS, false);
1092
 
1093
    for (page = base; page < base + size; page += PAGE_SIZE) {
1094
        pte = page_mapping_find(AS, page);
1095
        if (!pte || !PTE_PRESENT(pte) || !PTE_READABLE(pte)) {
1096
            /* Fetch the missing page */
1097
            if (!area->backend || !area->backend->page_fault) {
1098
                page_table_unlock(AS, false);
1099
                mutex_unlock(&area->lock);
1100
                mutex_unlock(&AS->lock);
1101
                interrupts_restore(ipl);
1102
                return EINVAL;
1103
            }
1104
            if (area->backend->page_fault(area, page, PF_ACCESS_READ) != AS_PF_OK) {
1105
                page_table_unlock(AS, false);
1106
                mutex_unlock(&area->lock);
1107
                mutex_unlock(&AS->lock);
1108
                interrupts_restore(ipl);
1109
                return EINVAL;
1110
            }
1111
        }
1112
        ASSERT(PTE_VALID(pte));
1113
 
1114
        old_frame = PTE_GET_FRAME(pte);
1115
 
1116
        frame = (uintptr_t)frame_alloc(ONE_FRAME, 0);
1117
        memcpy((void *) PA2KA(frame), (void *)PA2KA(old_frame),
1118
            FRAME_SIZE);
1119
 
1120
        pagemap[(page - base) / PAGE_SIZE] = frame;
1121
    }
1122
 
1123
    page_table_unlock(AS, false);
1124
    mutex_unlock(&area->lock);
1125
    mutex_unlock(&AS->lock);
1126
    interrupts_restore(ipl);
1127
 
1128
    rc = as_area_destroy(AS, address);
1129
    if (rc < 0) {
1130
        free(pagemap);
1131
        return rc;
1132
    }
1133
 
1134
    area = as_area_create(AS, flags, size, base, AS_AREA_ATTR_PARTIAL,
1135
        &anon_backend, NULL);
1136
    if (area == NULL) {
1137
        free(pagemap);
1138
        return rc;
1139
    }
1140
 
1141
    mutex_lock(&AS->lock);
1142
    mutex_lock(&area->lock);
1143
    page_table_lock(AS, false);
1144
    for (page = base; page < base + size; page += PAGE_SIZE) {
1145
        frame = pagemap[(page - base) / PAGE_SIZE];
1146
 
1147
        page_mapping_insert(AS, page, frame, page_flags);
1148
        if (!used_space_insert(area, page, 1))
1149
            panic("Could not insert used space.\n");
1150
    }
1151
 
1152
    page_table_unlock(AS, false);
1153
 
1154
    area->attributes &= ~AS_AREA_ATTR_PARTIAL;
1155
 
1156
    mutex_unlock(&area->lock);
1157
    mutex_unlock(&AS->lock);
1158
 
1159
    free(pagemap);
1160
 
1161
    return EOK;
1162
}
1163
 
1235 jermar 1164
/** Convert address space area flags to page flags.
754 jermar 1165
 *
1235 jermar 1166
 * @param aflags Flags of some address space area.
754 jermar 1167
 *
1235 jermar 1168
 * @return Flags to be passed to page_mapping_insert().
754 jermar 1169
 */
1235 jermar 1170
int area_flags_to_page_flags(int aflags)
754 jermar 1171
{
1172
    int flags;
1173
 
1178 jermar 1174
    flags = PAGE_USER | PAGE_PRESENT;
754 jermar 1175
 
1235 jermar 1176
    if (aflags & AS_AREA_READ)
1026 jermar 1177
        flags |= PAGE_READ;
1178
 
1235 jermar 1179
    if (aflags & AS_AREA_WRITE)
1026 jermar 1180
        flags |= PAGE_WRITE;
1181
 
1235 jermar 1182
    if (aflags & AS_AREA_EXEC)
1026 jermar 1183
        flags |= PAGE_EXEC;
1184
 
1424 jermar 1185
    if (aflags & AS_AREA_CACHEABLE)
1178 jermar 1186
        flags |= PAGE_CACHEABLE;
1187
 
754 jermar 1188
    return flags;
1189
}
756 jermar 1190
 
1235 jermar 1191
/** Compute flags for virtual address translation subsytem.
1192
 *
1193
 * The address space area must be locked.
1194
 * Interrupts must be disabled.
1195
 *
1196
 * @param a Address space area.
1197
 *
1198
 * @return Flags to be used in page_mapping_insert().
1199
 */
1409 jermar 1200
int as_area_get_flags(as_area_t *a)
1235 jermar 1201
{
1202
    return area_flags_to_page_flags(a->flags);
1203
}
1204
 
756 jermar 1205
/** Create page table.
1206
 *
1207
 * Depending on architecture, create either address space
1208
 * private or global page table.
1209
 *
1210
 * @param flags Flags saying whether the page table is for kernel address space.
1211
 *
1212
 * @return First entry of the page table.
1213
 */
1214
pte_t *page_table_create(int flags)
1215
{
2125 decky 1216
#ifdef __OBJC__
1217
    return [as_t page_table_create: flags];
1218
#else
1219
    ASSERT(as_operations);
1220
    ASSERT(as_operations->page_table_create);
1221
 
1222
    return as_operations->page_table_create(flags);
1223
#endif
756 jermar 1224
}
977 jermar 1225
 
1468 jermar 1226
/** Destroy page table.
1227
 *
1228
 * Destroy page table in architecture specific way.
1229
 *
1230
 * @param page_table Physical address of PTL0.
1231
 */
1232
void page_table_destroy(pte_t *page_table)
1233
{
2125 decky 1234
#ifdef __OBJC__
1235
    return [as_t page_table_destroy: page_table];
1236
#else
1237
    ASSERT(as_operations);
1238
    ASSERT(as_operations->page_table_destroy);
1239
 
1240
    as_operations->page_table_destroy(page_table);
1241
#endif
1468 jermar 1242
}
1243
 
1044 jermar 1244
/** Lock page table.
1245
 *
1246
 * This function should be called before any page_mapping_insert(),
1247
 * page_mapping_remove() and page_mapping_find().
1248
 *
1249
 * Locking order is such that address space areas must be locked
1250
 * prior to this call. Address space can be locked prior to this
1251
 * call in which case the lock argument is false.
1252
 *
1253
 * @param as Address space.
1248 jermar 1254
 * @param lock If false, do not attempt to lock as->lock.
1044 jermar 1255
 */
1256
void page_table_lock(as_t *as, bool lock)
1257
{
2125 decky 1258
#ifdef __OBJC__
1259
    [as page_table_lock: lock];
1260
#else
1044 jermar 1261
    ASSERT(as_operations);
1262
    ASSERT(as_operations->page_table_lock);
2125 decky 1263
 
1044 jermar 1264
    as_operations->page_table_lock(as, lock);
2125 decky 1265
#endif
1044 jermar 1266
}
1267
 
1268
/** Unlock page table.
1269
 *
1270
 * @param as Address space.
1248 jermar 1271
 * @param unlock If false, do not attempt to unlock as->lock.
1044 jermar 1272
 */
1273
void page_table_unlock(as_t *as, bool unlock)
1274
{
2125 decky 1275
#ifdef __OBJC__
1276
    [as page_table_unlock: unlock];
1277
#else
1044 jermar 1278
    ASSERT(as_operations);
1279
    ASSERT(as_operations->page_table_unlock);
2125 decky 1280
 
1044 jermar 1281
    as_operations->page_table_unlock(as, unlock);
2125 decky 1282
#endif
1044 jermar 1283
}
1284
 
977 jermar 1285
 
1286
/** Find address space area and lock it.
1287
 *
1288
 * The address space must be locked and interrupts must be disabled.
1289
 *
1290
 * @param as Address space.
1291
 * @param va Virtual address.
1292
 *
2087 jermar 1293
 * @return Locked address space area containing va on success or NULL on
1294
 *     failure.
977 jermar 1295
 */
1780 jermar 1296
as_area_t *find_area_and_lock(as_t *as, uintptr_t va)
977 jermar 1297
{
1298
    as_area_t *a;
1147 jermar 1299
    btree_node_t *leaf, *lnode;
2745 decky 1300
    unsigned int i;
977 jermar 1301
 
1147 jermar 1302
    a = (as_area_t *) btree_search(&as->as_area_btree, va, &leaf);
1303
    if (a) {
1304
        /* va is the base address of an address space area */
1380 jermar 1305
        mutex_lock(&a->lock);
1147 jermar 1306
        return a;
1307
    }
1308
 
1309
    /*
1150 jermar 1310
     * Search the leaf node and the righmost record of its left neighbour
1147 jermar 1311
     * to find out whether this is a miss or va belongs to an address
1312
     * space area found there.
1313
     */
1314
 
1315
    /* First, search the leaf node itself. */
1316
    for (i = 0; i < leaf->keys; i++) {
1317
        a = (as_area_t *) leaf->value[i];
1380 jermar 1318
        mutex_lock(&a->lock);
1147 jermar 1319
        if ((a->base <= va) && (va < a->base + a->pages * PAGE_SIZE)) {
1320
            return a;
1321
        }
1380 jermar 1322
        mutex_unlock(&a->lock);
1147 jermar 1323
    }
977 jermar 1324
 
1147 jermar 1325
    /*
1150 jermar 1326
     * Second, locate the left neighbour and test its last record.
1148 jermar 1327
     * Because of its position in the B+tree, it must have base < va.
1147 jermar 1328
     */
2087 jermar 1329
    lnode = btree_leaf_node_left_neighbour(&as->as_area_btree, leaf);
1330
    if (lnode) {
1147 jermar 1331
        a = (as_area_t *) lnode->value[lnode->keys - 1];
1380 jermar 1332
        mutex_lock(&a->lock);
1147 jermar 1333
        if (va < a->base + a->pages * PAGE_SIZE) {
1048 jermar 1334
            return a;
1147 jermar 1335
        }
1380 jermar 1336
        mutex_unlock(&a->lock);
977 jermar 1337
    }
1338
 
1339
    return NULL;
1340
}
1048 jermar 1341
 
1342
/** Check area conflicts with other areas.
1343
 *
1344
 * The address space must be locked and interrupts must be disabled.
1345
 *
1346
 * @param as Address space.
1347
 * @param va Starting virtual address of the area being tested.
1348
 * @param size Size of the area being tested.
1349
 * @param avoid_area Do not touch this area.
1350
 *
1351
 * @return True if there is no conflict, false otherwise.
1352
 */
2087 jermar 1353
bool check_area_conflicts(as_t *as, uintptr_t va, size_t size,
1354
              as_area_t *avoid_area)
1048 jermar 1355
{
1356
    as_area_t *a;
1147 jermar 1357
    btree_node_t *leaf, *node;
2745 decky 1358
    unsigned int i;
1048 jermar 1359
 
1070 jermar 1360
    /*
1361
     * We don't want any area to have conflicts with NULL page.
1362
     */
1363
    if (overlaps(va, size, NULL, PAGE_SIZE))
1364
        return false;
1365
 
1147 jermar 1366
    /*
1367
     * The leaf node is found in O(log n), where n is proportional to
1368
     * the number of address space areas belonging to as.
1369
     * The check for conflicts is then attempted on the rightmost
1150 jermar 1370
     * record in the left neighbour, the leftmost record in the right
1371
     * neighbour and all records in the leaf node itself.
1147 jermar 1372
     */
1048 jermar 1373
 
1147 jermar 1374
    if ((a = (as_area_t *) btree_search(&as->as_area_btree, va, &leaf))) {
1375
        if (a != avoid_area)
1376
            return false;
1377
    }
1378
 
1379
    /* First, check the two border cases. */
1150 jermar 1380
    if ((node = btree_leaf_node_left_neighbour(&as->as_area_btree, leaf))) {
1147 jermar 1381
        a = (as_area_t *) node->value[node->keys - 1];
1380 jermar 1382
        mutex_lock(&a->lock);
1147 jermar 1383
        if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
1380 jermar 1384
            mutex_unlock(&a->lock);
1147 jermar 1385
            return false;
1386
        }
1380 jermar 1387
        mutex_unlock(&a->lock);
1147 jermar 1388
    }
2087 jermar 1389
    node = btree_leaf_node_right_neighbour(&as->as_area_btree, leaf);
1390
    if (node) {
1147 jermar 1391
        a = (as_area_t *) node->value[0];
1380 jermar 1392
        mutex_lock(&a->lock);
1147 jermar 1393
        if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
1380 jermar 1394
            mutex_unlock(&a->lock);
1147 jermar 1395
            return false;
1396
        }
1380 jermar 1397
        mutex_unlock(&a->lock);
1147 jermar 1398
    }
1399
 
1400
    /* Second, check the leaf node. */
1401
    for (i = 0; i < leaf->keys; i++) {
1402
        a = (as_area_t *) leaf->value[i];
1403
 
1048 jermar 1404
        if (a == avoid_area)
1405
            continue;
1147 jermar 1406
 
1380 jermar 1407
        mutex_lock(&a->lock);
1147 jermar 1408
        if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
1380 jermar 1409
            mutex_unlock(&a->lock);
1147 jermar 1410
            return false;
1411
        }
1380 jermar 1412
        mutex_unlock(&a->lock);
1048 jermar 1413
    }
1414
 
1070 jermar 1415
    /*
1416
     * So far, the area does not conflict with other areas.
1417
     * Check if it doesn't conflict with kernel address space.
1418
     */  
1419
    if (!KERNEL_ADDRESS_SPACE_SHADOWED) {
1420
        return !overlaps(va, size,
2087 jermar 1421
            KERNEL_ADDRESS_SPACE_START,
1422
            KERNEL_ADDRESS_SPACE_END - KERNEL_ADDRESS_SPACE_START);
1070 jermar 1423
    }
1424
 
1048 jermar 1425
    return true;
1426
}
1235 jermar 1427
 
2556 jermar 1428
/** Return size of the address space area with given base.
1429
 *
1430
 * @param base      Arbitrary address insede the address space area.
1431
 *
1432
 * @return      Size of the address space area in bytes or zero if it
1433
 *          does not exist.
1434
 */
1435
size_t as_area_get_size(uintptr_t base)
1329 palkovsky 1436
{
1437
    ipl_t ipl;
1438
    as_area_t *src_area;
1439
    size_t size;
1440
 
1441
    ipl = interrupts_disable();
1442
    src_area = find_area_and_lock(AS, base);
1443
    if (src_area){
1444
        size = src_area->pages * PAGE_SIZE;
1380 jermar 1445
        mutex_unlock(&src_area->lock);
1329 palkovsky 1446
    } else {
1447
        size = 0;
1448
    }
1449
    interrupts_restore(ipl);
1450
    return size;
1451
}
1452
 
1387 jermar 1453
/** Mark portion of address space area as used.
1454
 *
1455
 * The address space area must be already locked.
1456
 *
1457
 * @param a Address space area.
1458
 * @param page First page to be marked.
1459
 * @param count Number of page to be marked.
1460
 *
1461
 * @return 0 on failure and 1 on success.
1462
 */
1780 jermar 1463
int used_space_insert(as_area_t *a, uintptr_t page, count_t count)
1387 jermar 1464
{
1465
    btree_node_t *leaf, *node;
1466
    count_t pages;
2745 decky 1467
    unsigned int i;
1387 jermar 1468
 
1469
    ASSERT(page == ALIGN_DOWN(page, PAGE_SIZE));
1470
    ASSERT(count);
1471
 
1472
    pages = (count_t) btree_search(&a->used_space, page, &leaf);
1473
    if (pages) {
1474
        /*
1475
         * We hit the beginning of some used space.
1476
         */
1477
        return 0;
1478
    }
1479
 
1437 jermar 1480
    if (!leaf->keys) {
1481
        btree_insert(&a->used_space, page, (void *) count, leaf);
1482
        return 1;
1483
    }
1484
 
1387 jermar 1485
    node = btree_leaf_node_left_neighbour(&a->used_space, leaf);
1486
    if (node) {
2087 jermar 1487
        uintptr_t left_pg = node->key[node->keys - 1];
1488
        uintptr_t right_pg = leaf->key[0];
1489
        count_t left_cnt = (count_t) node->value[node->keys - 1];
1490
        count_t right_cnt = (count_t) leaf->value[0];
1387 jermar 1491
 
1492
        /*
1493
         * Examine the possibility that the interval fits
1494
         * somewhere between the rightmost interval of
1495
         * the left neigbour and the first interval of the leaf.
1496
         */
1497
 
1498
        if (page >= right_pg) {
1499
            /* Do nothing. */
2087 jermar 1500
        } else if (overlaps(page, count * PAGE_SIZE, left_pg,
1501
            left_cnt * PAGE_SIZE)) {
1387 jermar 1502
            /* The interval intersects with the left interval. */
1503
            return 0;
2087 jermar 1504
        } else if (overlaps(page, count * PAGE_SIZE, right_pg,
1505
            right_cnt * PAGE_SIZE)) {
1387 jermar 1506
            /* The interval intersects with the right interval. */
1507
            return 0;          
2087 jermar 1508
        } else if ((page == left_pg + left_cnt * PAGE_SIZE) &&
1509
            (page + count * PAGE_SIZE == right_pg)) {
1510
            /*
1511
             * The interval can be added by merging the two already
1512
             * present intervals.
1513
             */
1403 jermar 1514
            node->value[node->keys - 1] += count + right_cnt;
1387 jermar 1515
            btree_remove(&a->used_space, right_pg, leaf);
1516
            return 1;
2087 jermar 1517
        } else if (page == left_pg + left_cnt * PAGE_SIZE) {
1518
            /*
1519
             * The interval can be added by simply growing the left
1520
             * interval.
1521
             */
1403 jermar 1522
            node->value[node->keys - 1] += count;
1387 jermar 1523
            return 1;
2087 jermar 1524
        } else if (page + count * PAGE_SIZE == right_pg) {
1387 jermar 1525
            /*
2087 jermar 1526
             * The interval can be addded by simply moving base of
1527
             * the right interval down and increasing its size
1528
             * accordingly.
1387 jermar 1529
             */
1403 jermar 1530
            leaf->value[0] += count;
1387 jermar 1531
            leaf->key[0] = page;
1532
            return 1;
1533
        } else {
1534
            /*
1535
             * The interval is between both neigbouring intervals,
1536
             * but cannot be merged with any of them.
1537
             */
2087 jermar 1538
            btree_insert(&a->used_space, page, (void *) count,
1539
                leaf);
1387 jermar 1540
            return 1;
1541
        }
1542
    } else if (page < leaf->key[0]) {
1780 jermar 1543
        uintptr_t right_pg = leaf->key[0];
1387 jermar 1544
        count_t right_cnt = (count_t) leaf->value[0];
1545
 
1546
        /*
2087 jermar 1547
         * Investigate the border case in which the left neighbour does
1548
         * not exist but the interval fits from the left.
1387 jermar 1549
         */
1550
 
2087 jermar 1551
        if (overlaps(page, count * PAGE_SIZE, right_pg,
1552
            right_cnt * PAGE_SIZE)) {
1387 jermar 1553
            /* The interval intersects with the right interval. */
1554
            return 0;
2087 jermar 1555
        } else if (page + count * PAGE_SIZE == right_pg) {
1387 jermar 1556
            /*
2087 jermar 1557
             * The interval can be added by moving the base of the
1558
             * right interval down and increasing its size
1559
             * accordingly.
1387 jermar 1560
             */
1561
            leaf->key[0] = page;
1403 jermar 1562
            leaf->value[0] += count;
1387 jermar 1563
            return 1;
1564
        } else {
1565
            /*
1566
             * The interval doesn't adjoin with the right interval.
1567
             * It must be added individually.
1568
             */
2087 jermar 1569
            btree_insert(&a->used_space, page, (void *) count,
1570
                leaf);
1387 jermar 1571
            return 1;
1572
        }
1573
    }
1574
 
1575
    node = btree_leaf_node_right_neighbour(&a->used_space, leaf);
1576
    if (node) {
2087 jermar 1577
        uintptr_t left_pg = leaf->key[leaf->keys - 1];
1578
        uintptr_t right_pg = node->key[0];
1579
        count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
1580
        count_t right_cnt = (count_t) node->value[0];
1387 jermar 1581
 
1582
        /*
1583
         * Examine the possibility that the interval fits
1584
         * somewhere between the leftmost interval of
1585
         * the right neigbour and the last interval of the leaf.
1586
         */
1587
 
1588
        if (page < left_pg) {
1589
            /* Do nothing. */
2087 jermar 1590
        } else if (overlaps(page, count * PAGE_SIZE, left_pg,
1591
            left_cnt * PAGE_SIZE)) {
1387 jermar 1592
            /* The interval intersects with the left interval. */
1593
            return 0;
2087 jermar 1594
        } else if (overlaps(page, count * PAGE_SIZE, right_pg,
1595
            right_cnt * PAGE_SIZE)) {
1387 jermar 1596
            /* The interval intersects with the right interval. */
1597
            return 0;          
2087 jermar 1598
        } else if ((page == left_pg + left_cnt * PAGE_SIZE) &&
1599
            (page + count * PAGE_SIZE == right_pg)) {
1600
            /*
1601
             * The interval can be added by merging the two already
1602
             * present intervals.
1603
             * */
1403 jermar 1604
            leaf->value[leaf->keys - 1] += count + right_cnt;
1387 jermar 1605
            btree_remove(&a->used_space, right_pg, node);
1606
            return 1;
2087 jermar 1607
        } else if (page == left_pg + left_cnt * PAGE_SIZE) {
1608
            /*
1609
             * The interval can be added by simply growing the left
1610
             * interval.
1611
             * */
1403 jermar 1612
            leaf->value[leaf->keys - 1] +=  count;
1387 jermar 1613
            return 1;
2087 jermar 1614
        } else if (page + count * PAGE_SIZE == right_pg) {
1387 jermar 1615
            /*
2087 jermar 1616
             * The interval can be addded by simply moving base of
1617
             * the right interval down and increasing its size
1618
             * accordingly.
1387 jermar 1619
             */
1403 jermar 1620
            node->value[0] += count;
1387 jermar 1621
            node->key[0] = page;
1622
            return 1;
1623
        } else {
1624
            /*
1625
             * The interval is between both neigbouring intervals,
1626
             * but cannot be merged with any of them.
1627
             */
2087 jermar 1628
            btree_insert(&a->used_space, page, (void *) count,
1629
                leaf);
1387 jermar 1630
            return 1;
1631
        }
1632
    } else if (page >= leaf->key[leaf->keys - 1]) {
1780 jermar 1633
        uintptr_t left_pg = leaf->key[leaf->keys - 1];
1387 jermar 1634
        count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
1635
 
1636
        /*
2087 jermar 1637
         * Investigate the border case in which the right neighbour
1638
         * does not exist but the interval fits from the right.
1387 jermar 1639
         */
1640
 
2087 jermar 1641
        if (overlaps(page, count * PAGE_SIZE, left_pg,
1642
            left_cnt * PAGE_SIZE)) {
1403 jermar 1643
            /* The interval intersects with the left interval. */
1387 jermar 1644
            return 0;
2087 jermar 1645
        } else if (left_pg + left_cnt * PAGE_SIZE == page) {
1646
            /*
1647
             * The interval can be added by growing the left
1648
             * interval.
1649
             */
1403 jermar 1650
            leaf->value[leaf->keys - 1] += count;
1387 jermar 1651
            return 1;
1652
        } else {
1653
            /*
1654
             * The interval doesn't adjoin with the left interval.
1655
             * It must be added individually.
1656
             */
2087 jermar 1657
            btree_insert(&a->used_space, page, (void *) count,
1658
                leaf);
1387 jermar 1659
            return 1;
1660
        }
1661
    }
1662
 
1663
    /*
2087 jermar 1664
     * Note that if the algorithm made it thus far, the interval can fit
1665
     * only between two other intervals of the leaf. The two border cases
1666
     * were already resolved.
1387 jermar 1667
     */
1668
    for (i = 1; i < leaf->keys; i++) {
1669
        if (page < leaf->key[i]) {
2087 jermar 1670
            uintptr_t left_pg = leaf->key[i - 1];
1671
            uintptr_t right_pg = leaf->key[i];
1672
            count_t left_cnt = (count_t) leaf->value[i - 1];
1673
            count_t right_cnt = (count_t) leaf->value[i];
1387 jermar 1674
 
1675
            /*
1676
             * The interval fits between left_pg and right_pg.
1677
             */
1678
 
2087 jermar 1679
            if (overlaps(page, count * PAGE_SIZE, left_pg,
1680
                left_cnt * PAGE_SIZE)) {
1681
                /*
1682
                 * The interval intersects with the left
1683
                 * interval.
1684
                 */
1387 jermar 1685
                return 0;
2087 jermar 1686
            } else if (overlaps(page, count * PAGE_SIZE, right_pg,
1687
                right_cnt * PAGE_SIZE)) {
1688
                /*
1689
                 * The interval intersects with the right
1690
                 * interval.
1691
                 */
1387 jermar 1692
                return 0;          
2087 jermar 1693
            } else if ((page == left_pg + left_cnt * PAGE_SIZE) &&
1694
                (page + count * PAGE_SIZE == right_pg)) {
1695
                /*
1696
                 * The interval can be added by merging the two
1697
                 * already present intervals.
1698
                 */
1403 jermar 1699
                leaf->value[i - 1] += count + right_cnt;
1387 jermar 1700
                btree_remove(&a->used_space, right_pg, leaf);
1701
                return 1;
2087 jermar 1702
            } else if (page == left_pg + left_cnt * PAGE_SIZE) {
1703
                /*
1704
                 * The interval can be added by simply growing
1705
                 * the left interval.
1706
                 */
1403 jermar 1707
                leaf->value[i - 1] += count;
1387 jermar 1708
                return 1;
2087 jermar 1709
            } else if (page + count * PAGE_SIZE == right_pg) {
1387 jermar 1710
                /*
2087 jermar 1711
                     * The interval can be addded by simply moving
1712
                 * base of the right interval down and
1713
                 * increasing its size accordingly.
1387 jermar 1714
                 */
1403 jermar 1715
                leaf->value[i] += count;
1387 jermar 1716
                leaf->key[i] = page;
1717
                return 1;
1718
            } else {
1719
                /*
2087 jermar 1720
                 * The interval is between both neigbouring
1721
                 * intervals, but cannot be merged with any of
1722
                 * them.
1387 jermar 1723
                 */
2087 jermar 1724
                btree_insert(&a->used_space, page,
1725
                    (void *) count, leaf);
1387 jermar 1726
                return 1;
1727
            }
1728
        }
1729
    }
1730
 
2087 jermar 1731
    panic("Inconsistency detected while adding %d pages of used space at "
1732
        "%p.\n", count, page);
1387 jermar 1733
}
1734
 
1735
/** Mark portion of address space area as unused.
1736
 *
1737
 * The address space area must be already locked.
1738
 *
1739
 * @param a Address space area.
1740
 * @param page First page to be marked.
1741
 * @param count Number of page to be marked.
1742
 *
1743
 * @return 0 on failure and 1 on success.
1744
 */
1780 jermar 1745
int used_space_remove(as_area_t *a, uintptr_t page, count_t count)
1387 jermar 1746
{
1747
    btree_node_t *leaf, *node;
1748
    count_t pages;
2745 decky 1749
    unsigned int i;
1387 jermar 1750
 
1751
    ASSERT(page == ALIGN_DOWN(page, PAGE_SIZE));
1752
    ASSERT(count);
1753
 
1754
    pages = (count_t) btree_search(&a->used_space, page, &leaf);
1755
    if (pages) {
1756
        /*
1757
         * We are lucky, page is the beginning of some interval.
1758
         */
1759
        if (count > pages) {
1760
            return 0;
1761
        } else if (count == pages) {
1762
            btree_remove(&a->used_space, page, leaf);
1403 jermar 1763
            return 1;
1387 jermar 1764
        } else {
1765
            /*
1766
             * Find the respective interval.
1767
             * Decrease its size and relocate its start address.
1768
             */
1769
            for (i = 0; i < leaf->keys; i++) {
1770
                if (leaf->key[i] == page) {
2087 jermar 1771
                    leaf->key[i] += count * PAGE_SIZE;
1403 jermar 1772
                    leaf->value[i] -= count;
1387 jermar 1773
                    return 1;
1774
                }
1775
            }
1776
            goto error;
1777
        }
1778
    }
1779
 
1780
    node = btree_leaf_node_left_neighbour(&a->used_space, leaf);
1781
    if (node && page < leaf->key[0]) {
1780 jermar 1782
        uintptr_t left_pg = node->key[node->keys - 1];
1387 jermar 1783
        count_t left_cnt = (count_t) node->value[node->keys - 1];
1784
 
2087 jermar 1785
        if (overlaps(left_pg, left_cnt * PAGE_SIZE, page,
1786
            count * PAGE_SIZE)) {
1787
            if (page + count * PAGE_SIZE ==
1788
                left_pg + left_cnt * PAGE_SIZE) {
1387 jermar 1789
                /*
2087 jermar 1790
                 * The interval is contained in the rightmost
1791
                 * interval of the left neighbour and can be
1792
                 * removed by updating the size of the bigger
1793
                 * interval.
1387 jermar 1794
                 */
1403 jermar 1795
                node->value[node->keys - 1] -= count;
1387 jermar 1796
                return 1;
2087 jermar 1797
            } else if (page + count * PAGE_SIZE <
1798
                left_pg + left_cnt*PAGE_SIZE) {
1403 jermar 1799
                count_t new_cnt;
1387 jermar 1800
 
1801
                /*
2087 jermar 1802
                 * The interval is contained in the rightmost
1803
                 * interval of the left neighbour but its
1804
                 * removal requires both updating the size of
1805
                 * the original interval and also inserting a
1806
                 * new interval.
1387 jermar 1807
                 */
2087 jermar 1808
                new_cnt = ((left_pg + left_cnt * PAGE_SIZE) -
1809
                    (page + count*PAGE_SIZE)) >> PAGE_WIDTH;
1403 jermar 1810
                node->value[node->keys - 1] -= count + new_cnt;
2087 jermar 1811
                btree_insert(&a->used_space, page +
1812
                    count * PAGE_SIZE, (void *) new_cnt, leaf);
1387 jermar 1813
                return 1;
1814
            }
1815
        }
1816
        return 0;
1817
    } else if (page < leaf->key[0]) {
1818
        return 0;
1819
    }
1820
 
1821
    if (page > leaf->key[leaf->keys - 1]) {
1780 jermar 1822
        uintptr_t left_pg = leaf->key[leaf->keys - 1];
1387 jermar 1823
        count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
1824
 
2087 jermar 1825
        if (overlaps(left_pg, left_cnt * PAGE_SIZE, page,
1826
            count * PAGE_SIZE)) {
1827
            if (page + count * PAGE_SIZE ==
1828
                left_pg + left_cnt * PAGE_SIZE) {
1387 jermar 1829
                /*
2087 jermar 1830
                 * The interval is contained in the rightmost
1831
                 * interval of the leaf and can be removed by
1832
                 * updating the size of the bigger interval.
1387 jermar 1833
                 */
1403 jermar 1834
                leaf->value[leaf->keys - 1] -= count;
1387 jermar 1835
                return 1;
2087 jermar 1836
            } else if (page + count * PAGE_SIZE < left_pg +
1837
                left_cnt * PAGE_SIZE) {
1403 jermar 1838
                count_t new_cnt;
1387 jermar 1839
 
1840
                /*
2087 jermar 1841
                 * The interval is contained in the rightmost
1842
                 * interval of the leaf but its removal
1843
                 * requires both updating the size of the
1844
                 * original interval and also inserting a new
1845
                 * interval.
1387 jermar 1846
                 */
2087 jermar 1847
                new_cnt = ((left_pg + left_cnt * PAGE_SIZE) -
1848
                    (page + count * PAGE_SIZE)) >> PAGE_WIDTH;
1403 jermar 1849
                leaf->value[leaf->keys - 1] -= count + new_cnt;
2087 jermar 1850
                btree_insert(&a->used_space, page +
1851
                    count * PAGE_SIZE, (void *) new_cnt, leaf);
1387 jermar 1852
                return 1;
1853
            }
1854
        }
1855
        return 0;
1856
    }  
1857
 
1858
    /*
1859
     * The border cases have been already resolved.
1860
     * Now the interval can be only between intervals of the leaf.
1861
     */
1862
    for (i = 1; i < leaf->keys - 1; i++) {
1863
        if (page < leaf->key[i]) {
1780 jermar 1864
            uintptr_t left_pg = leaf->key[i - 1];
1387 jermar 1865
            count_t left_cnt = (count_t) leaf->value[i - 1];
1866
 
1867
            /*
2087 jermar 1868
             * Now the interval is between intervals corresponding
1869
             * to (i - 1) and i.
1387 jermar 1870
             */
2087 jermar 1871
            if (overlaps(left_pg, left_cnt * PAGE_SIZE, page,
1872
                count * PAGE_SIZE)) {
1873
                if (page + count * PAGE_SIZE ==
1874
                    left_pg + left_cnt*PAGE_SIZE) {
1387 jermar 1875
                    /*
2087 jermar 1876
                     * The interval is contained in the
1877
                     * interval (i - 1) of the leaf and can
1878
                     * be removed by updating the size of
1879
                     * the bigger interval.
1387 jermar 1880
                     */
1403 jermar 1881
                    leaf->value[i - 1] -= count;
1387 jermar 1882
                    return 1;
2087 jermar 1883
                } else if (page + count * PAGE_SIZE <
1884
                    left_pg + left_cnt * PAGE_SIZE) {
1403 jermar 1885
                    count_t new_cnt;
1387 jermar 1886
 
1887
                    /*
2087 jermar 1888
                     * The interval is contained in the
1889
                     * interval (i - 1) of the leaf but its
1890
                     * removal requires both updating the
1891
                     * size of the original interval and
1387 jermar 1892
                     * also inserting a new interval.
1893
                     */
2087 jermar 1894
                    new_cnt = ((left_pg +
1895
                        left_cnt * PAGE_SIZE) -
1896
                        (page + count * PAGE_SIZE)) >>
1897
                        PAGE_WIDTH;
1403 jermar 1898
                    leaf->value[i - 1] -= count + new_cnt;
2087 jermar 1899
                    btree_insert(&a->used_space, page +
1900
                        count * PAGE_SIZE, (void *) new_cnt,
1901
                        leaf);
1387 jermar 1902
                    return 1;
1903
                }
1904
            }
1905
            return 0;
1906
        }
1907
    }
1908
 
1909
error:
2087 jermar 1910
    panic("Inconsistency detected while removing %d pages of used space "
1911
        "from %p.\n", count, page);
1387 jermar 1912
}
1913
 
1409 jermar 1914
/** Remove reference to address space area share info.
1915
 *
1916
 * If the reference count drops to 0, the sh_info is deallocated.
1917
 *
1918
 * @param sh_info Pointer to address space area share info.
1919
 */
1920
void sh_info_remove_reference(share_info_t *sh_info)
1921
{
1922
    bool dealloc = false;
1923
 
1924
    mutex_lock(&sh_info->lock);
1925
    ASSERT(sh_info->refcount);
1926
    if (--sh_info->refcount == 0) {
1927
        dealloc = true;
1495 jermar 1928
        link_t *cur;
1409 jermar 1929
 
1930
        /*
1931
         * Now walk carefully the pagemap B+tree and free/remove
1932
         * reference from all frames found there.
1933
         */
2087 jermar 1934
        for (cur = sh_info->pagemap.leaf_head.next;
1935
            cur != &sh_info->pagemap.leaf_head; cur = cur->next) {
1409 jermar 1936
            btree_node_t *node;
2745 decky 1937
            unsigned int i;
1409 jermar 1938
 
1495 jermar 1939
            node = list_get_instance(cur, btree_node_t, leaf_link);
1940
            for (i = 0; i < node->keys; i++)
1780 jermar 1941
                frame_free((uintptr_t) node->value[i]);
1409 jermar 1942
        }
1943
 
1944
    }
1945
    mutex_unlock(&sh_info->lock);
1946
 
1947
    if (dealloc) {
1948
        btree_destroy(&sh_info->pagemap);
1949
        free(sh_info);
1950
    }
1951
}
1952
 
1235 jermar 1953
/*
1954
 * Address space related syscalls.
1955
 */
1956
 
1957
/** Wrapper for as_area_create(). */
1780 jermar 1958
unative_t sys_as_area_create(uintptr_t address, size_t size, int flags)
1235 jermar 1959
{
2087 jermar 1960
    if (as_area_create(AS, flags | AS_AREA_CACHEABLE, size, address,
1961
        AS_AREA_ATTR_NONE, &anon_backend, NULL))
1780 jermar 1962
        return (unative_t) address;
1235 jermar 1963
    else
1780 jermar 1964
        return (unative_t) -1;
1235 jermar 1965
}
1966
 
1793 jermar 1967
/** Wrapper for as_area_resize(). */
1780 jermar 1968
unative_t sys_as_area_resize(uintptr_t address, size_t size, int flags)
1235 jermar 1969
{
1780 jermar 1970
    return (unative_t) as_area_resize(AS, address, size, 0);
1235 jermar 1971
}
1972
 
1793 jermar 1973
/** Wrapper for as_area_destroy(). */
1780 jermar 1974
unative_t sys_as_area_destroy(uintptr_t address)
1306 jermar 1975
{
1780 jermar 1976
    return (unative_t) as_area_destroy(AS, address);
1306 jermar 1977
}
1702 cejka 1978
 
1914 jermar 1979
/** Print out information about address space.
1980
 *
1981
 * @param as Address space.
1982
 */
1983
void as_print(as_t *as)
1984
{
1985
    ipl_t ipl;
1986
 
1987
    ipl = interrupts_disable();
1988
    mutex_lock(&as->lock);
1989
 
1990
    /* print out info about address space areas */
1991
    link_t *cur;
2087 jermar 1992
    for (cur = as->as_area_btree.leaf_head.next;
1993
        cur != &as->as_area_btree.leaf_head; cur = cur->next) {
1994
        btree_node_t *node;
1914 jermar 1995
 
2087 jermar 1996
        node = list_get_instance(cur, btree_node_t, leaf_link);
1997
 
2745 decky 1998
        unsigned int i;
1914 jermar 1999
        for (i = 0; i < node->keys; i++) {
1915 jermar 2000
            as_area_t *area = node->value[i];
1914 jermar 2001
 
2002
            mutex_lock(&area->lock);
2003
            printf("as_area: %p, base=%p, pages=%d (%p - %p)\n",
2087 jermar 2004
                area, area->base, area->pages, area->base,
2005
                area->base + area->pages*PAGE_SIZE);
1914 jermar 2006
            mutex_unlock(&area->lock);
2007
        }
2008
    }
2009
 
2010
    mutex_unlock(&as->lock);
2011
    interrupts_restore(ipl);
2012
}
2013
 
1757 jermar 2014
/** @}
1702 cejka 2015
 */