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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
 
1235 jermar 114
static int area_flags_to_page_flags(int aflags);
1780 jermar 115
static as_area_t *find_area_and_lock(as_t *as, uintptr_t va);
2087 jermar 116
static bool check_area_conflicts(as_t *as, uintptr_t va, size_t size,
117
    as_area_t *avoid_area);
1409 jermar 118
static void sh_info_remove_reference(share_info_t *sh_info);
703 jermar 119
 
1891 jermar 120
static int as_constructor(void *obj, int flags)
121
{
122
    as_t *as = (as_t *) obj;
123
    int rc;
124
 
125
    link_initialize(&as->inactive_as_with_asid_link);
3186 jermar 126
    mutex_initialize(&as->lock, MUTEX_PASSIVE);
1891 jermar 127
 
128
    rc = as_constructor_arch(as, flags);
129
 
130
    return rc;
131
}
132
 
133
static int as_destructor(void *obj)
134
{
135
    as_t *as = (as_t *) obj;
136
 
137
    return as_destructor_arch(as);
138
}
139
 
756 jermar 140
/** Initialize address space subsystem. */
141
void as_init(void)
142
{
143
    as_arch_init();
2126 decky 144
 
1891 jermar 145
    as_slab = slab_cache_create("as_slab", sizeof(as_t), 0,
2087 jermar 146
        as_constructor, as_destructor, SLAB_CACHE_MAGDEFERRED);
1890 jermar 147
 
789 palkovsky 148
    AS_KERNEL = as_create(FLAG_AS_KERNEL);
1383 decky 149
    if (!AS_KERNEL)
150
        panic("can't create kernel address space\n");
151
 
756 jermar 152
}
153
 
757 jermar 154
/** Create address space.
155
 *
156
 * @param flags Flags that influence way in wich the address space is created.
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.
1468 jermar 189
 */
190
void as_destroy(as_t *as)
973 palkovsky 191
{
1468 jermar 192
    ipl_t ipl;
1594 jermar 193
    bool cond;
2183 jermar 194
    DEADLOCK_PROBE_INIT(p_asidlock);
973 palkovsky 195
 
2183 jermar 196
    ASSERT(atomic_get(&as->refcount) == 0);
1468 jermar 197
 
198
    /*
199
     * Since there is no reference to this area,
200
     * it is safe not to lock its mutex.
201
     */
2170 jermar 202
 
2183 jermar 203
    /*
204
     * We need to avoid deadlock between TLB shootdown and asidlock.
205
     * We therefore try to take asid conditionally and if we don't succeed,
206
     * we enable interrupts and try again. This is done while preemption is
207
     * disabled to prevent nested context switches. We also depend on the
208
     * fact that so far no spinlocks are held.
209
     */
210
    preemption_disable();
211
    ipl = interrupts_read();
212
retry:
213
    interrupts_disable();
214
    if (!spinlock_trylock(&asidlock)) {
215
        interrupts_enable();
216
        DEADLOCK_PROBE(p_asidlock, DEADLOCK_THRESHOLD);
217
        goto retry;
218
    }
219
    preemption_enable();    /* Interrupts disabled, enable preemption */
1587 jermar 220
    if (as->asid != ASID_INVALID && as != AS_KERNEL) {
1594 jermar 221
        if (as != AS && as->cpu_refcount == 0)
1587 jermar 222
            list_remove(&as->inactive_as_with_asid_link);
1468 jermar 223
        asid_put(as->asid);
224
    }
2170 jermar 225
    spinlock_unlock(&asidlock);
1468 jermar 226
 
227
    /*
228
     * Destroy address space areas of the address space.
1954 jermar 229
     * The B+tree must be walked carefully because it is
1594 jermar 230
     * also being destroyed.
1468 jermar 231
     */
1594 jermar 232
    for (cond = true; cond; ) {
1468 jermar 233
        btree_node_t *node;
1594 jermar 234
 
235
        ASSERT(!list_empty(&as->as_area_btree.leaf_head));
2087 jermar 236
        node = list_get_instance(as->as_area_btree.leaf_head.next,
237
            btree_node_t, leaf_link);
1594 jermar 238
 
239
        if ((cond = node->keys)) {
240
            as_area_destroy(as, node->key[0]);
241
        }
1468 jermar 242
    }
1495 jermar 243
 
1483 jermar 244
    btree_destroy(&as->as_area_btree);
2089 decky 245
#ifdef AS_PAGE_TABLE
2106 jermar 246
    page_table_destroy(as->genarch.page_table);
2089 decky 247
#else
248
    page_table_destroy(NULL);
249
#endif
1468 jermar 250
 
251
    interrupts_restore(ipl);
2126 decky 252
 
1890 jermar 253
    slab_free(as_slab, as);
973 palkovsky 254
}
255
 
703 jermar 256
/** Create address space area of common attributes.
257
 *
258
 * The created address space area is added to the target address space.
259
 *
260
 * @param as Target address space.
1239 jermar 261
 * @param flags Flags of the area memory.
1048 jermar 262
 * @param size Size of area.
703 jermar 263
 * @param base Base address of area.
1239 jermar 264
 * @param attrs Attributes of the area.
1409 jermar 265
 * @param backend Address space area backend. NULL if no backend is used.
266
 * @param backend_data NULL or a pointer to an array holding two void *.
703 jermar 267
 *
268
 * @return Address space area on success or NULL on failure.
269
 */
2069 jermar 270
as_area_t *
271
as_area_create(as_t *as, int flags, size_t size, uintptr_t base, int attrs,
1424 jermar 272
           mem_backend_t *backend, mem_backend_data_t *backend_data)
703 jermar 273
{
274
    ipl_t ipl;
275
    as_area_t *a;
276
 
277
    if (base % PAGE_SIZE)
1048 jermar 278
        return NULL;
279
 
1233 jermar 280
    if (!size)
281
        return NULL;
282
 
1048 jermar 283
    /* Writeable executable areas are not supported. */
284
    if ((flags & AS_AREA_EXEC) && (flags & AS_AREA_WRITE))
285
        return NULL;
703 jermar 286
 
287
    ipl = interrupts_disable();
1380 jermar 288
    mutex_lock(&as->lock);
703 jermar 289
 
1048 jermar 290
    if (!check_area_conflicts(as, base, size, NULL)) {
1380 jermar 291
        mutex_unlock(&as->lock);
1048 jermar 292
        interrupts_restore(ipl);
293
        return NULL;
294
    }
703 jermar 295
 
822 palkovsky 296
    a = (as_area_t *) malloc(sizeof(as_area_t), 0);
703 jermar 297
 
3186 jermar 298
    mutex_initialize(&a->lock, MUTEX_PASSIVE);
822 palkovsky 299
 
1424 jermar 300
    a->as = as;
1026 jermar 301
    a->flags = flags;
1239 jermar 302
    a->attributes = attrs;
1048 jermar 303
    a->pages = SIZE2FRAMES(size);
822 palkovsky 304
    a->base = base;
1409 jermar 305
    a->sh_info = NULL;
306
    a->backend = backend;
1424 jermar 307
    if (backend_data)
308
        a->backend_data = *backend_data;
309
    else
3104 svoboda 310
        memsetb(&a->backend_data, sizeof(a->backend_data), 0);
1424 jermar 311
 
1387 jermar 312
    btree_create(&a->used_space);
822 palkovsky 313
 
1147 jermar 314
    btree_insert(&as->as_area_btree, base, (void *) a, NULL);
822 palkovsky 315
 
1380 jermar 316
    mutex_unlock(&as->lock);
703 jermar 317
    interrupts_restore(ipl);
704 jermar 318
 
703 jermar 319
    return a;
320
}
321
 
1235 jermar 322
/** Find address space area and change it.
323
 *
324
 * @param as Address space.
2087 jermar 325
 * @param address Virtual address belonging to the area to be changed. Must be
326
 *     page-aligned.
1235 jermar 327
 * @param size New size of the virtual memory block starting at address.
328
 * @param flags Flags influencing the remap operation. Currently unused.
329
 *
1306 jermar 330
 * @return Zero on success or a value from @ref errno.h otherwise.
1235 jermar 331
 */
1780 jermar 332
int as_area_resize(as_t *as, uintptr_t address, size_t size, int flags)
1235 jermar 333
{
1306 jermar 334
    as_area_t *area;
1235 jermar 335
    ipl_t ipl;
336
    size_t pages;
337
 
338
    ipl = interrupts_disable();
1380 jermar 339
    mutex_lock(&as->lock);
1235 jermar 340
 
341
    /*
342
     * Locate the area.
343
     */
344
    area = find_area_and_lock(as, address);
345
    if (!area) {
1380 jermar 346
        mutex_unlock(&as->lock);
1235 jermar 347
        interrupts_restore(ipl);
1306 jermar 348
        return ENOENT;
1235 jermar 349
    }
350
 
1424 jermar 351
    if (area->backend == &phys_backend) {
1235 jermar 352
        /*
353
         * Remapping of address space areas associated
354
         * with memory mapped devices is not supported.
355
         */
1380 jermar 356
        mutex_unlock(&area->lock);
357
        mutex_unlock(&as->lock);
1235 jermar 358
        interrupts_restore(ipl);
1306 jermar 359
        return ENOTSUP;
1235 jermar 360
    }
1409 jermar 361
    if (area->sh_info) {
362
        /*
363
         * Remapping of shared address space areas
364
         * is not supported.
365
         */
366
        mutex_unlock(&area->lock);
367
        mutex_unlock(&as->lock);
368
        interrupts_restore(ipl);
369
        return ENOTSUP;
370
    }
1235 jermar 371
 
372
    pages = SIZE2FRAMES((address - area->base) + size);
373
    if (!pages) {
374
        /*
375
         * Zero size address space areas are not allowed.
376
         */
1380 jermar 377
        mutex_unlock(&area->lock);
378
        mutex_unlock(&as->lock);
1235 jermar 379
        interrupts_restore(ipl);
1306 jermar 380
        return EPERM;
1235 jermar 381
    }
382
 
383
    if (pages < area->pages) {
1403 jermar 384
        bool cond;
1780 jermar 385
        uintptr_t start_free = area->base + pages*PAGE_SIZE;
1235 jermar 386
 
387
        /*
388
         * Shrinking the area.
389
         * No need to check for overlaps.
390
         */
1403 jermar 391
 
392
        /*
1436 jermar 393
         * Start TLB shootdown sequence.
394
         */
2087 jermar 395
        tlb_shootdown_start(TLB_INVL_PAGES, AS->asid, area->base +
396
            pages * PAGE_SIZE, area->pages - pages);
1436 jermar 397
 
398
        /*
1403 jermar 399
         * Remove frames belonging to used space starting from
400
         * the highest addresses downwards until an overlap with
401
         * the resized address space area is found. Note that this
402
         * is also the right way to remove part of the used_space
403
         * B+tree leaf list.
404
         */    
405
        for (cond = true; cond;) {
406
            btree_node_t *node;
407
 
408
            ASSERT(!list_empty(&area->used_space.leaf_head));
2087 jermar 409
            node =
410
                list_get_instance(area->used_space.leaf_head.prev,
411
                btree_node_t, leaf_link);
1403 jermar 412
            if ((cond = (bool) node->keys)) {
1780 jermar 413
                uintptr_t b = node->key[node->keys - 1];
2087 jermar 414
                count_t c =
415
                    (count_t) node->value[node->keys - 1];
2745 decky 416
                unsigned int i = 0;
1235 jermar 417
 
2087 jermar 418
                if (overlaps(b, c * PAGE_SIZE, area->base,
2133 jermar 419
                    pages * PAGE_SIZE)) {
1403 jermar 420
 
2087 jermar 421
                    if (b + c * PAGE_SIZE <= start_free) {
1403 jermar 422
                        /*
2087 jermar 423
                         * The whole interval fits
424
                         * completely in the resized
425
                         * address space area.
1403 jermar 426
                         */
427
                        break;
428
                    }
429
 
430
                    /*
2087 jermar 431
                     * Part of the interval corresponding
432
                     * to b and c overlaps with the resized
433
                     * address space area.
1403 jermar 434
                     */
435
 
436
                    cond = false;   /* we are almost done */
437
                    i = (start_free - b) >> PAGE_WIDTH;
3057 decky 438
                    if (!used_space_remove(area, start_free, c - i))
439
                        panic("Could not remove used space.\n");
1403 jermar 440
                } else {
441
                    /*
2087 jermar 442
                     * The interval of used space can be
443
                     * completely removed.
1403 jermar 444
                     */
445
                    if (!used_space_remove(area, b, c))
3057 decky 446
                        panic("Could not remove used space.\n");
1403 jermar 447
                }
448
 
449
                for (; i < c; i++) {
450
                    pte_t *pte;
451
 
452
                    page_table_lock(as, false);
2087 jermar 453
                    pte = page_mapping_find(as, b +
454
                        i * PAGE_SIZE);
455
                    ASSERT(pte && PTE_VALID(pte) &&
456
                        PTE_PRESENT(pte));
457
                    if (area->backend &&
458
                        area->backend->frame_free) {
1424 jermar 459
                        area->backend->frame_free(area,
2087 jermar 460
                            b + i * PAGE_SIZE,
461
                            PTE_GET_FRAME(pte));
1409 jermar 462
                    }
2087 jermar 463
                    page_mapping_remove(as, b +
464
                        i * PAGE_SIZE);
1403 jermar 465
                    page_table_unlock(as, false);
466
                }
1235 jermar 467
            }
468
        }
1436 jermar 469
 
1235 jermar 470
        /*
1436 jermar 471
         * Finish TLB shootdown sequence.
1235 jermar 472
         */
2183 jermar 473
 
2087 jermar 474
        tlb_invalidate_pages(as->asid, area->base + pages * PAGE_SIZE,
475
            area->pages - pages);
1889 jermar 476
        /*
477
         * Invalidate software translation caches (e.g. TSB on sparc64).
478
         */
2087 jermar 479
        as_invalidate_translation_cache(as, area->base +
480
            pages * PAGE_SIZE, area->pages - pages);
2183 jermar 481
        tlb_shootdown_finalize();
482
 
1235 jermar 483
    } else {
484
        /*
485
         * Growing the area.
486
         * Check for overlaps with other address space areas.
487
         */
2087 jermar 488
        if (!check_area_conflicts(as, address, pages * PAGE_SIZE,
489
            area)) {
1380 jermar 490
            mutex_unlock(&area->lock);
491
            mutex_unlock(&as->lock);       
1235 jermar 492
            interrupts_restore(ipl);
1306 jermar 493
            return EADDRNOTAVAIL;
1235 jermar 494
        }
495
    }
496
 
497
    area->pages = pages;
498
 
1380 jermar 499
    mutex_unlock(&area->lock);
500
    mutex_unlock(&as->lock);
1235 jermar 501
    interrupts_restore(ipl);
502
 
1306 jermar 503
    return 0;
1235 jermar 504
}
505
 
1306 jermar 506
/** Destroy address space area.
507
 *
508
 * @param as Address space.
509
 * @param address Address withing the area to be deleted.
510
 *
511
 * @return Zero on success or a value from @ref errno.h on failure.
512
 */
1780 jermar 513
int as_area_destroy(as_t *as, uintptr_t address)
1306 jermar 514
{
515
    as_area_t *area;
1780 jermar 516
    uintptr_t base;
1495 jermar 517
    link_t *cur;
1306 jermar 518
    ipl_t ipl;
519
 
520
    ipl = interrupts_disable();
1380 jermar 521
    mutex_lock(&as->lock);
1306 jermar 522
 
523
    area = find_area_and_lock(as, address);
524
    if (!area) {
1380 jermar 525
        mutex_unlock(&as->lock);
1306 jermar 526
        interrupts_restore(ipl);
527
        return ENOENT;
528
    }
529
 
1403 jermar 530
    base = area->base;
531
 
1411 jermar 532
    /*
1436 jermar 533
     * Start TLB shootdown sequence.
534
     */
1889 jermar 535
    tlb_shootdown_start(TLB_INVL_PAGES, as->asid, area->base, area->pages);
1436 jermar 536
 
537
    /*
1411 jermar 538
     * Visit only the pages mapped by used_space B+tree.
539
     */
2087 jermar 540
    for (cur = area->used_space.leaf_head.next;
541
        cur != &area->used_space.leaf_head; cur = cur->next) {
1411 jermar 542
        btree_node_t *node;
2745 decky 543
        unsigned int i;
1403 jermar 544
 
1495 jermar 545
        node = list_get_instance(cur, btree_node_t, leaf_link);
546
        for (i = 0; i < node->keys; i++) {
1780 jermar 547
            uintptr_t b = node->key[i];
1495 jermar 548
            count_t j;
1411 jermar 549
            pte_t *pte;
1403 jermar 550
 
1495 jermar 551
            for (j = 0; j < (count_t) node->value[i]; j++) {
1411 jermar 552
                page_table_lock(as, false);
2087 jermar 553
                pte = page_mapping_find(as, b + j * PAGE_SIZE);
554
                ASSERT(pte && PTE_VALID(pte) &&
555
                    PTE_PRESENT(pte));
556
                if (area->backend &&
557
                    area->backend->frame_free) {
558
                    area->backend->frame_free(area, b +
2133 jermar 559
                        j * PAGE_SIZE, PTE_GET_FRAME(pte));
1403 jermar 560
                }
2087 jermar 561
                page_mapping_remove(as, b + j * PAGE_SIZE);            
1411 jermar 562
                page_table_unlock(as, false);
1306 jermar 563
            }
564
        }
565
    }
1403 jermar 566
 
1306 jermar 567
    /*
1436 jermar 568
     * Finish TLB shootdown sequence.
1306 jermar 569
     */
2183 jermar 570
 
1889 jermar 571
    tlb_invalidate_pages(as->asid, area->base, area->pages);
572
    /*
2087 jermar 573
     * Invalidate potential software translation caches (e.g. TSB on
574
     * sparc64).
1889 jermar 575
     */
576
    as_invalidate_translation_cache(as, area->base, area->pages);
2183 jermar 577
    tlb_shootdown_finalize();
1889 jermar 578
 
1436 jermar 579
    btree_destroy(&area->used_space);
1306 jermar 580
 
1309 jermar 581
    area->attributes |= AS_AREA_ATTR_PARTIAL;
1409 jermar 582
 
583
    if (area->sh_info)
584
        sh_info_remove_reference(area->sh_info);
585
 
1380 jermar 586
    mutex_unlock(&area->lock);
1306 jermar 587
 
588
    /*
589
     * Remove the empty area from address space.
590
     */
1889 jermar 591
    btree_remove(&as->as_area_btree, base, NULL);
1306 jermar 592
 
1309 jermar 593
    free(area);
594
 
1889 jermar 595
    mutex_unlock(&as->lock);
1306 jermar 596
    interrupts_restore(ipl);
597
    return 0;
598
}
599
 
1413 jermar 600
/** Share address space area with another or the same address space.
1235 jermar 601
 *
1424 jermar 602
 * Address space area mapping is shared with a new address space area.
603
 * If the source address space area has not been shared so far,
604
 * a new sh_info is created. The new address space area simply gets the
605
 * sh_info of the source area. The process of duplicating the
606
 * mapping is done through the backend share function.
1413 jermar 607
 *
1417 jermar 608
 * @param src_as Pointer to source address space.
1239 jermar 609
 * @param src_base Base address of the source address space area.
1417 jermar 610
 * @param acc_size Expected size of the source area.
1428 palkovsky 611
 * @param dst_as Pointer to destination address space.
1417 jermar 612
 * @param dst_base Target base address.
613
 * @param dst_flags_mask Destination address space area flags mask.
1235 jermar 614
 *
2007 jermar 615
 * @return Zero on success or ENOENT if there is no such task or if there is no
616
 * such address space area, EPERM if there was a problem in accepting the area
617
 * or ENOMEM if there was a problem in allocating destination address space
618
 * area. ENOTSUP is returned if the address space area backend does not support
2141 jermar 619
 * sharing.
1235 jermar 620
 */
1780 jermar 621
int as_area_share(as_t *src_as, uintptr_t src_base, size_t acc_size,
2647 jermar 622
    as_t *dst_as, uintptr_t dst_base, int dst_flags_mask)
1235 jermar 623
{
624
    ipl_t ipl;
1239 jermar 625
    int src_flags;
626
    size_t src_size;
627
    as_area_t *src_area, *dst_area;
1413 jermar 628
    share_info_t *sh_info;
1424 jermar 629
    mem_backend_t *src_backend;
630
    mem_backend_data_t src_backend_data;
1434 palkovsky 631
 
1235 jermar 632
    ipl = interrupts_disable();
1380 jermar 633
    mutex_lock(&src_as->lock);
1329 palkovsky 634
    src_area = find_area_and_lock(src_as, src_base);
1239 jermar 635
    if (!src_area) {
1238 jermar 636
        /*
637
         * Could not find the source address space area.
638
         */
1380 jermar 639
        mutex_unlock(&src_as->lock);
1238 jermar 640
        interrupts_restore(ipl);
641
        return ENOENT;
642
    }
2007 jermar 643
 
1424 jermar 644
    if (!src_area->backend || !src_area->backend->share) {
1413 jermar 645
        /*
1851 jermar 646
         * There is no backend or the backend does not
1424 jermar 647
         * know how to share the area.
1413 jermar 648
         */
649
        mutex_unlock(&src_area->lock);
650
        mutex_unlock(&src_as->lock);
651
        interrupts_restore(ipl);
652
        return ENOTSUP;
653
    }
654
 
1239 jermar 655
    src_size = src_area->pages * PAGE_SIZE;
656
    src_flags = src_area->flags;
1424 jermar 657
    src_backend = src_area->backend;
658
    src_backend_data = src_area->backend_data;
1544 palkovsky 659
 
660
    /* Share the cacheable flag from the original mapping */
661
    if (src_flags & AS_AREA_CACHEABLE)
662
        dst_flags_mask |= AS_AREA_CACHEABLE;
663
 
2087 jermar 664
    if (src_size != acc_size ||
665
        (src_flags & dst_flags_mask) != dst_flags_mask) {
1413 jermar 666
        mutex_unlock(&src_area->lock);
667
        mutex_unlock(&src_as->lock);
1235 jermar 668
        interrupts_restore(ipl);
669
        return EPERM;
670
    }
1413 jermar 671
 
1235 jermar 672
    /*
1413 jermar 673
     * Now we are committed to sharing the area.
1954 jermar 674
     * First, prepare the area for sharing.
1413 jermar 675
     * Then it will be safe to unlock it.
676
     */
677
    sh_info = src_area->sh_info;
678
    if (!sh_info) {
679
        sh_info = (share_info_t *) malloc(sizeof(share_info_t), 0);
3186 jermar 680
        mutex_initialize(&sh_info->lock, MUTEX_PASSIVE);
1413 jermar 681
        sh_info->refcount = 2;
682
        btree_create(&sh_info->pagemap);
683
        src_area->sh_info = sh_info;
2647 jermar 684
        /*
685
         * Call the backend to setup sharing.
686
         */
687
        src_area->backend->share(src_area);
1413 jermar 688
    } else {
689
        mutex_lock(&sh_info->lock);
690
        sh_info->refcount++;
691
        mutex_unlock(&sh_info->lock);
692
    }
693
 
694
    mutex_unlock(&src_area->lock);
695
    mutex_unlock(&src_as->lock);
696
 
697
    /*
1239 jermar 698
     * Create copy of the source address space area.
699
     * The destination area is created with AS_AREA_ATTR_PARTIAL
700
     * attribute set which prevents race condition with
701
     * preliminary as_page_fault() calls.
1417 jermar 702
     * The flags of the source area are masked against dst_flags_mask
703
     * to support sharing in less privileged mode.
1235 jermar 704
     */
1461 palkovsky 705
    dst_area = as_area_create(dst_as, dst_flags_mask, src_size, dst_base,
2087 jermar 706
        AS_AREA_ATTR_PARTIAL, src_backend, &src_backend_data);
1239 jermar 707
    if (!dst_area) {
1235 jermar 708
        /*
709
         * Destination address space area could not be created.
710
         */
1413 jermar 711
        sh_info_remove_reference(sh_info);
712
 
1235 jermar 713
        interrupts_restore(ipl);
714
        return ENOMEM;
715
    }
2009 jermar 716
 
1235 jermar 717
    /*
1239 jermar 718
     * Now the destination address space area has been
719
     * fully initialized. Clear the AS_AREA_ATTR_PARTIAL
1413 jermar 720
     * attribute and set the sh_info.
1239 jermar 721
     */
2009 jermar 722
    mutex_lock(&dst_as->lock); 
1380 jermar 723
    mutex_lock(&dst_area->lock);
1239 jermar 724
    dst_area->attributes &= ~AS_AREA_ATTR_PARTIAL;
1413 jermar 725
    dst_area->sh_info = sh_info;
1380 jermar 726
    mutex_unlock(&dst_area->lock);
2009 jermar 727
    mutex_unlock(&dst_as->lock);   
728
 
1235 jermar 729
    interrupts_restore(ipl);
730
 
731
    return 0;
732
}
733
 
1423 jermar 734
/** Check access mode for address space area.
735
 *
736
 * The address space area must be locked prior to this call.
737
 *
738
 * @param area Address space area.
739
 * @param access Access mode.
740
 *
741
 * @return False if access violates area's permissions, true otherwise.
742
 */
743
bool as_area_check_access(as_area_t *area, pf_access_t access)
744
{
745
    int flagmap[] = {
746
        [PF_ACCESS_READ] = AS_AREA_READ,
747
        [PF_ACCESS_WRITE] = AS_AREA_WRITE,
748
        [PF_ACCESS_EXEC] = AS_AREA_EXEC
749
    };
750
 
751
    if (!(area->flags & flagmap[access]))
752
        return false;
753
 
754
    return true;
755
}
756
 
3222 svoboda 757
/** Change adress area flags.
758
 *
759
 * The idea is to have the same data, but with a different access mode.
760
 * This is needed e.g. for writing code into memory and then executing it.
761
 * In order for this to work properly, this may copy the data
762
 * into private anonymous memory (unless it's already there).
763
 *
764
 * @param as Address space.
765
 * @param flags Flags of the area memory.
766
 * @param address Address withing the area to be changed.
767
 *
768
 * @return Zero on success or a value from @ref errno.h on failure.
769
 */
770
int as_area_change_flags(as_t *as, int flags, uintptr_t address)
771
{
772
    as_area_t *area;
773
    uintptr_t base;
774
    link_t *cur;
775
    ipl_t ipl;
776
    int page_flags;
777
    uintptr_t *old_frame;
778
    index_t frame_idx;
779
    count_t used_pages;
780
 
781
    /* Flags for the new memory mapping */
782
    page_flags = area_flags_to_page_flags(flags);
783
 
784
    ipl = interrupts_disable();
785
    mutex_lock(&as->lock);
786
 
787
    area = find_area_and_lock(as, address);
788
    if (!area) {
789
        mutex_unlock(&as->lock);
790
        interrupts_restore(ipl);
791
        return ENOENT;
792
    }
793
 
794
    if (area->sh_info || area->backend != &anon_backend) {
795
        /* Copying shared areas not supported yet */
796
        /* Copying non-anonymous memory not supported yet */
797
        mutex_unlock(&area->lock);
798
        mutex_unlock(&as->lock);
799
        interrupts_restore(ipl);
800
        return ENOTSUP;
801
    }
802
 
803
    base = area->base;
804
 
805
    /*
806
     * Compute total number of used pages in the used_space B+tree
807
     */
808
    used_pages = 0;
809
 
810
    for (cur = area->used_space.leaf_head.next;
811
        cur != &area->used_space.leaf_head; cur = cur->next) {
812
        btree_node_t *node;
813
        unsigned int i;
814
 
815
        node = list_get_instance(cur, btree_node_t, leaf_link);
816
        for (i = 0; i < node->keys; i++) {
817
            used_pages += (count_t) node->value[i];
818
        }
819
    }
820
 
821
    /* An array for storing frame numbers */
822
    old_frame = malloc(used_pages * sizeof(uintptr_t), 0);
823
 
824
    /*
825
     * Start TLB shootdown sequence.
826
     */
827
    tlb_shootdown_start(TLB_INVL_PAGES, as->asid, area->base, area->pages);
828
 
829
    /*
830
     * Remove used pages from page tables and remember their frame
831
     * numbers.
832
     */
833
    frame_idx = 0;
834
 
835
    for (cur = area->used_space.leaf_head.next;
836
        cur != &area->used_space.leaf_head; cur = cur->next) {
837
        btree_node_t *node;
838
        unsigned int i;
839
 
840
        node = list_get_instance(cur, btree_node_t, leaf_link);
841
        for (i = 0; i < node->keys; i++) {
842
            uintptr_t b = node->key[i];
843
            count_t j;
844
            pte_t *pte;
845
 
846
            for (j = 0; j < (count_t) node->value[i]; j++) {
847
                page_table_lock(as, false);
848
                pte = page_mapping_find(as, b + j * PAGE_SIZE);
849
                ASSERT(pte && PTE_VALID(pte) &&
850
                    PTE_PRESENT(pte));
851
                old_frame[frame_idx++] = PTE_GET_FRAME(pte);
852
 
853
                /* Remove old mapping */
854
                page_mapping_remove(as, b + j * PAGE_SIZE);
855
                page_table_unlock(as, false);
856
            }
857
        }
858
    }
859
 
860
    /*
861
     * Finish TLB shootdown sequence.
862
     */
863
 
864
    tlb_invalidate_pages(as->asid, area->base, area->pages);
865
    /*
866
     * Invalidate potential software translation caches (e.g. TSB on
867
     * sparc64).
868
     */
869
    as_invalidate_translation_cache(as, area->base, area->pages);
870
    tlb_shootdown_finalize();
871
 
872
    /*
873
     * Map pages back in with new flags. This step is kept separate
874
     * so that there's no instant when the memory area could be
875
     * accesed with both the old and the new flags at once.
876
     */
877
    frame_idx = 0;
878
 
879
    for (cur = area->used_space.leaf_head.next;
880
        cur != &area->used_space.leaf_head; cur = cur->next) {
881
        btree_node_t *node;
882
        unsigned int i;
883
 
884
        node = list_get_instance(cur, btree_node_t, leaf_link);
885
        for (i = 0; i < node->keys; i++) {
886
            uintptr_t b = node->key[i];
887
            count_t j;
888
 
889
            for (j = 0; j < (count_t) node->value[i]; j++) {
890
                page_table_lock(as, false);
891
 
892
                /* Insert the new mapping */
893
                page_mapping_insert(as, b + j * PAGE_SIZE,
894
                    old_frame[frame_idx++], page_flags);
895
 
896
                page_table_unlock(as, false);
897
            }
898
        }
899
    }
900
 
901
    free(old_frame);
902
 
903
    mutex_unlock(&area->lock);
904
    mutex_unlock(&as->lock);
905
    interrupts_restore(ipl);
906
 
907
    return 0;
908
}
909
 
910
 
703 jermar 911
/** Handle page fault within the current address space.
912
 *
1409 jermar 913
 * This is the high-level page fault handler. It decides
914
 * whether the page fault can be resolved by any backend
915
 * and if so, it invokes the backend to resolve the page
916
 * fault.
917
 *
703 jermar 918
 * Interrupts are assumed disabled.
919
 *
920
 * @param page Faulting page.
1411 jermar 921
 * @param access Access mode that caused the fault (i.e. read/write/exec).
1288 jermar 922
 * @param istate Pointer to interrupted state.
703 jermar 923
 *
1409 jermar 924
 * @return AS_PF_FAULT on page fault, AS_PF_OK on success or AS_PF_DEFER if the
925
 *     fault was caused by copy_to_uspace() or copy_from_uspace().
703 jermar 926
 */
1780 jermar 927
int as_page_fault(uintptr_t page, pf_access_t access, istate_t *istate)
703 jermar 928
{
1044 jermar 929
    pte_t *pte;
977 jermar 930
    as_area_t *area;
703 jermar 931
 
1380 jermar 932
    if (!THREAD)
1409 jermar 933
        return AS_PF_FAULT;
1380 jermar 934
 
703 jermar 935
    ASSERT(AS);
1044 jermar 936
 
1380 jermar 937
    mutex_lock(&AS->lock);
977 jermar 938
    area = find_area_and_lock(AS, page);   
703 jermar 939
    if (!area) {
940
        /*
941
         * No area contained mapping for 'page'.
942
         * Signal page fault to low-level handler.
943
         */
1380 jermar 944
        mutex_unlock(&AS->lock);
1288 jermar 945
        goto page_fault;
703 jermar 946
    }
947
 
1239 jermar 948
    if (area->attributes & AS_AREA_ATTR_PARTIAL) {
949
        /*
950
         * The address space area is not fully initialized.
951
         * Avoid possible race by returning error.
952
         */
1380 jermar 953
        mutex_unlock(&area->lock);
954
        mutex_unlock(&AS->lock);
1288 jermar 955
        goto page_fault;       
1239 jermar 956
    }
957
 
1424 jermar 958
    if (!area->backend || !area->backend->page_fault) {
1409 jermar 959
        /*
960
         * The address space area is not backed by any backend
961
         * or the backend cannot handle page faults.
962
         */
963
        mutex_unlock(&area->lock);
964
        mutex_unlock(&AS->lock);
965
        goto page_fault;       
966
    }
1179 jermar 967
 
1044 jermar 968
    page_table_lock(AS, false);
969
 
703 jermar 970
    /*
1044 jermar 971
     * To avoid race condition between two page faults
972
     * on the same address, we need to make sure
973
     * the mapping has not been already inserted.
974
     */
975
    if ((pte = page_mapping_find(AS, page))) {
976
        if (PTE_PRESENT(pte)) {
1423 jermar 977
            if (((access == PF_ACCESS_READ) && PTE_READABLE(pte)) ||
2087 jermar 978
                (access == PF_ACCESS_WRITE && PTE_WRITABLE(pte)) ||
979
                (access == PF_ACCESS_EXEC && PTE_EXECUTABLE(pte))) {
1423 jermar 980
                page_table_unlock(AS, false);
981
                mutex_unlock(&area->lock);
982
                mutex_unlock(&AS->lock);
983
                return AS_PF_OK;
984
            }
1044 jermar 985
        }
986
    }
1409 jermar 987
 
1044 jermar 988
    /*
1409 jermar 989
     * Resort to the backend page fault handler.
703 jermar 990
     */
1424 jermar 991
    if (area->backend->page_fault(area, page, access) != AS_PF_OK) {
1409 jermar 992
        page_table_unlock(AS, false);
993
        mutex_unlock(&area->lock);
994
        mutex_unlock(&AS->lock);
995
        goto page_fault;
996
    }
703 jermar 997
 
1044 jermar 998
    page_table_unlock(AS, false);
1380 jermar 999
    mutex_unlock(&area->lock);
1000
    mutex_unlock(&AS->lock);
1288 jermar 1001
    return AS_PF_OK;
1002
 
1003
page_fault:
1004
    if (THREAD->in_copy_from_uspace) {
1005
        THREAD->in_copy_from_uspace = false;
2087 jermar 1006
        istate_set_retaddr(istate,
1007
            (uintptr_t) &memcpy_from_uspace_failover_address);
1288 jermar 1008
    } else if (THREAD->in_copy_to_uspace) {
1009
        THREAD->in_copy_to_uspace = false;
2087 jermar 1010
        istate_set_retaddr(istate,
1011
            (uintptr_t) &memcpy_to_uspace_failover_address);
1288 jermar 1012
    } else {
1013
        return AS_PF_FAULT;
1014
    }
1015
 
1016
    return AS_PF_DEFER;
703 jermar 1017
}
1018
 
823 jermar 1019
/** Switch address spaces.
703 jermar 1020
 *
1380 jermar 1021
 * Note that this function cannot sleep as it is essentially a part of
2170 jermar 1022
 * scheduling. Sleeping here would lead to deadlock on wakeup. Another
1023
 * thing which is forbidden in this context is locking the address space.
1380 jermar 1024
 *
2183 jermar 1025
 * When this function is enetered, no spinlocks may be held.
1026
 *
823 jermar 1027
 * @param old Old address space or NULL.
1028
 * @param new New address space.
703 jermar 1029
 */
2106 jermar 1030
void as_switch(as_t *old_as, as_t *new_as)
703 jermar 1031
{
2183 jermar 1032
    DEADLOCK_PROBE_INIT(p_asidlock);
1033
    preemption_disable();
1034
retry:
1035
    (void) interrupts_disable();
1036
    if (!spinlock_trylock(&asidlock)) {
1037
        /*
1038
         * Avoid deadlock with TLB shootdown.
1039
         * We can enable interrupts here because
1040
         * preemption is disabled. We should not be
1041
         * holding any other lock.
1042
         */
1043
        (void) interrupts_enable();
1044
        DEADLOCK_PROBE(p_asidlock, DEADLOCK_THRESHOLD);
1045
        goto retry;
1046
    }
1047
    preemption_enable();
703 jermar 1048
 
1049
    /*
823 jermar 1050
     * First, take care of the old address space.
1051
     */
2106 jermar 1052
    if (old_as) {
1053
        ASSERT(old_as->cpu_refcount);
1054
        if((--old_as->cpu_refcount == 0) && (old_as != AS_KERNEL)) {
823 jermar 1055
            /*
1056
             * The old address space is no longer active on
1057
             * any processor. It can be appended to the
1058
             * list of inactive address spaces with assigned
1059
             * ASID.
1060
             */
2141 jermar 1061
            ASSERT(old_as->asid != ASID_INVALID);
1062
            list_append(&old_as->inactive_as_with_asid_link,
1063
                &inactive_as_with_asid_head);
823 jermar 1064
        }
1890 jermar 1065
 
1066
        /*
1067
         * Perform architecture-specific tasks when the address space
1068
         * is being removed from the CPU.
1069
         */
2106 jermar 1070
        as_deinstall_arch(old_as);
823 jermar 1071
    }
1072
 
1073
    /*
1074
     * Second, prepare the new address space.
1075
     */
2106 jermar 1076
    if ((new_as->cpu_refcount++ == 0) && (new_as != AS_KERNEL)) {
2170 jermar 1077
        if (new_as->asid != ASID_INVALID)
2106 jermar 1078
            list_remove(&new_as->inactive_as_with_asid_link);
2170 jermar 1079
        else
1080
            new_as->asid = asid_get();
823 jermar 1081
    }
2106 jermar 1082
#ifdef AS_PAGE_TABLE
1083
    SET_PTL0_ADDRESS(new_as->genarch.page_table);
1084
#endif
823 jermar 1085
 
1086
    /*
703 jermar 1087
     * Perform architecture-specific steps.
727 jermar 1088
     * (e.g. write ASID to hardware register etc.)
703 jermar 1089
     */
2106 jermar 1090
    as_install_arch(new_as);
2170 jermar 1091
 
1092
    spinlock_unlock(&asidlock);
703 jermar 1093
 
2106 jermar 1094
    AS = new_as;
703 jermar 1095
}
754 jermar 1096
 
1235 jermar 1097
/** Convert address space area flags to page flags.
754 jermar 1098
 *
1235 jermar 1099
 * @param aflags Flags of some address space area.
754 jermar 1100
 *
1235 jermar 1101
 * @return Flags to be passed to page_mapping_insert().
754 jermar 1102
 */
1235 jermar 1103
int area_flags_to_page_flags(int aflags)
754 jermar 1104
{
1105
    int flags;
1106
 
1178 jermar 1107
    flags = PAGE_USER | PAGE_PRESENT;
754 jermar 1108
 
1235 jermar 1109
    if (aflags & AS_AREA_READ)
1026 jermar 1110
        flags |= PAGE_READ;
1111
 
1235 jermar 1112
    if (aflags & AS_AREA_WRITE)
1026 jermar 1113
        flags |= PAGE_WRITE;
1114
 
1235 jermar 1115
    if (aflags & AS_AREA_EXEC)
1026 jermar 1116
        flags |= PAGE_EXEC;
1117
 
1424 jermar 1118
    if (aflags & AS_AREA_CACHEABLE)
1178 jermar 1119
        flags |= PAGE_CACHEABLE;
1120
 
754 jermar 1121
    return flags;
1122
}
756 jermar 1123
 
1235 jermar 1124
/** Compute flags for virtual address translation subsytem.
1125
 *
1126
 * The address space area must be locked.
1127
 * Interrupts must be disabled.
1128
 *
1129
 * @param a Address space area.
1130
 *
1131
 * @return Flags to be used in page_mapping_insert().
1132
 */
1409 jermar 1133
int as_area_get_flags(as_area_t *a)
1235 jermar 1134
{
1135
    return area_flags_to_page_flags(a->flags);
1136
}
1137
 
756 jermar 1138
/** Create page table.
1139
 *
1140
 * Depending on architecture, create either address space
1141
 * private or global page table.
1142
 *
1143
 * @param flags Flags saying whether the page table is for kernel address space.
1144
 *
1145
 * @return First entry of the page table.
1146
 */
1147
pte_t *page_table_create(int flags)
1148
{
2125 decky 1149
    ASSERT(as_operations);
1150
    ASSERT(as_operations->page_table_create);
1151
 
1152
    return as_operations->page_table_create(flags);
756 jermar 1153
}
977 jermar 1154
 
1468 jermar 1155
/** Destroy page table.
1156
 *
1157
 * Destroy page table in architecture specific way.
1158
 *
1159
 * @param page_table Physical address of PTL0.
1160
 */
1161
void page_table_destroy(pte_t *page_table)
1162
{
2125 decky 1163
    ASSERT(as_operations);
1164
    ASSERT(as_operations->page_table_destroy);
1165
 
1166
    as_operations->page_table_destroy(page_table);
1468 jermar 1167
}
1168
 
1044 jermar 1169
/** Lock page table.
1170
 *
1171
 * This function should be called before any page_mapping_insert(),
1172
 * page_mapping_remove() and page_mapping_find().
1173
 *
1174
 * Locking order is such that address space areas must be locked
1175
 * prior to this call. Address space can be locked prior to this
1176
 * call in which case the lock argument is false.
1177
 *
1178
 * @param as Address space.
1248 jermar 1179
 * @param lock If false, do not attempt to lock as->lock.
1044 jermar 1180
 */
1181
void page_table_lock(as_t *as, bool lock)
1182
{
1183
    ASSERT(as_operations);
1184
    ASSERT(as_operations->page_table_lock);
2125 decky 1185
 
1044 jermar 1186
    as_operations->page_table_lock(as, lock);
1187
}
1188
 
1189
/** Unlock page table.
1190
 *
1191
 * @param as Address space.
1248 jermar 1192
 * @param unlock If false, do not attempt to unlock as->lock.
1044 jermar 1193
 */
1194
void page_table_unlock(as_t *as, bool unlock)
1195
{
1196
    ASSERT(as_operations);
1197
    ASSERT(as_operations->page_table_unlock);
2125 decky 1198
 
1044 jermar 1199
    as_operations->page_table_unlock(as, unlock);
1200
}
1201
 
977 jermar 1202
 
1203
/** Find address space area and lock it.
1204
 *
1205
 * The address space must be locked and interrupts must be disabled.
1206
 *
1207
 * @param as Address space.
1208
 * @param va Virtual address.
1209
 *
2087 jermar 1210
 * @return Locked address space area containing va on success or NULL on
1211
 *     failure.
977 jermar 1212
 */
1780 jermar 1213
as_area_t *find_area_and_lock(as_t *as, uintptr_t va)
977 jermar 1214
{
1215
    as_area_t *a;
1147 jermar 1216
    btree_node_t *leaf, *lnode;
2745 decky 1217
    unsigned int i;
977 jermar 1218
 
1147 jermar 1219
    a = (as_area_t *) btree_search(&as->as_area_btree, va, &leaf);
1220
    if (a) {
1221
        /* va is the base address of an address space area */
1380 jermar 1222
        mutex_lock(&a->lock);
1147 jermar 1223
        return a;
1224
    }
1225
 
1226
    /*
1150 jermar 1227
     * Search the leaf node and the righmost record of its left neighbour
1147 jermar 1228
     * to find out whether this is a miss or va belongs to an address
1229
     * space area found there.
1230
     */
1231
 
1232
    /* First, search the leaf node itself. */
1233
    for (i = 0; i < leaf->keys; i++) {
1234
        a = (as_area_t *) leaf->value[i];
1380 jermar 1235
        mutex_lock(&a->lock);
1147 jermar 1236
        if ((a->base <= va) && (va < a->base + a->pages * PAGE_SIZE)) {
1237
            return a;
1238
        }
1380 jermar 1239
        mutex_unlock(&a->lock);
1147 jermar 1240
    }
977 jermar 1241
 
1147 jermar 1242
    /*
1150 jermar 1243
     * Second, locate the left neighbour and test its last record.
1148 jermar 1244
     * Because of its position in the B+tree, it must have base < va.
1147 jermar 1245
     */
2087 jermar 1246
    lnode = btree_leaf_node_left_neighbour(&as->as_area_btree, leaf);
1247
    if (lnode) {
1147 jermar 1248
        a = (as_area_t *) lnode->value[lnode->keys - 1];
1380 jermar 1249
        mutex_lock(&a->lock);
1147 jermar 1250
        if (va < a->base + a->pages * PAGE_SIZE) {
1048 jermar 1251
            return a;
1147 jermar 1252
        }
1380 jermar 1253
        mutex_unlock(&a->lock);
977 jermar 1254
    }
1255
 
1256
    return NULL;
1257
}
1048 jermar 1258
 
1259
/** Check area conflicts with other areas.
1260
 *
1261
 * The address space must be locked and interrupts must be disabled.
1262
 *
1263
 * @param as Address space.
1264
 * @param va Starting virtual address of the area being tested.
1265
 * @param size Size of the area being tested.
1266
 * @param avoid_area Do not touch this area.
1267
 *
1268
 * @return True if there is no conflict, false otherwise.
1269
 */
2087 jermar 1270
bool check_area_conflicts(as_t *as, uintptr_t va, size_t size,
1271
              as_area_t *avoid_area)
1048 jermar 1272
{
1273
    as_area_t *a;
1147 jermar 1274
    btree_node_t *leaf, *node;
2745 decky 1275
    unsigned int i;
1048 jermar 1276
 
1070 jermar 1277
    /*
1278
     * We don't want any area to have conflicts with NULL page.
1279
     */
1280
    if (overlaps(va, size, NULL, PAGE_SIZE))
1281
        return false;
1282
 
1147 jermar 1283
    /*
1284
     * The leaf node is found in O(log n), where n is proportional to
1285
     * the number of address space areas belonging to as.
1286
     * The check for conflicts is then attempted on the rightmost
1150 jermar 1287
     * record in the left neighbour, the leftmost record in the right
1288
     * neighbour and all records in the leaf node itself.
1147 jermar 1289
     */
1048 jermar 1290
 
1147 jermar 1291
    if ((a = (as_area_t *) btree_search(&as->as_area_btree, va, &leaf))) {
1292
        if (a != avoid_area)
1293
            return false;
1294
    }
1295
 
1296
    /* First, check the two border cases. */
1150 jermar 1297
    if ((node = btree_leaf_node_left_neighbour(&as->as_area_btree, leaf))) {
1147 jermar 1298
        a = (as_area_t *) node->value[node->keys - 1];
1380 jermar 1299
        mutex_lock(&a->lock);
1147 jermar 1300
        if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
1380 jermar 1301
            mutex_unlock(&a->lock);
1147 jermar 1302
            return false;
1303
        }
1380 jermar 1304
        mutex_unlock(&a->lock);
1147 jermar 1305
    }
2087 jermar 1306
    node = btree_leaf_node_right_neighbour(&as->as_area_btree, leaf);
1307
    if (node) {
1147 jermar 1308
        a = (as_area_t *) node->value[0];
1380 jermar 1309
        mutex_lock(&a->lock);
1147 jermar 1310
        if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
1380 jermar 1311
            mutex_unlock(&a->lock);
1147 jermar 1312
            return false;
1313
        }
1380 jermar 1314
        mutex_unlock(&a->lock);
1147 jermar 1315
    }
1316
 
1317
    /* Second, check the leaf node. */
1318
    for (i = 0; i < leaf->keys; i++) {
1319
        a = (as_area_t *) leaf->value[i];
1320
 
1048 jermar 1321
        if (a == avoid_area)
1322
            continue;
1147 jermar 1323
 
1380 jermar 1324
        mutex_lock(&a->lock);
1147 jermar 1325
        if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
1380 jermar 1326
            mutex_unlock(&a->lock);
1147 jermar 1327
            return false;
1328
        }
1380 jermar 1329
        mutex_unlock(&a->lock);
1048 jermar 1330
    }
1331
 
1070 jermar 1332
    /*
1333
     * So far, the area does not conflict with other areas.
1334
     * Check if it doesn't conflict with kernel address space.
1335
     */  
1336
    if (!KERNEL_ADDRESS_SPACE_SHADOWED) {
1337
        return !overlaps(va, size,
2087 jermar 1338
            KERNEL_ADDRESS_SPACE_START,
1339
            KERNEL_ADDRESS_SPACE_END - KERNEL_ADDRESS_SPACE_START);
1070 jermar 1340
    }
1341
 
1048 jermar 1342
    return true;
1343
}
1235 jermar 1344
 
2556 jermar 1345
/** Return size of the address space area with given base.
1346
 *
1347
 * @param base      Arbitrary address insede the address space area.
1348
 *
1349
 * @return      Size of the address space area in bytes or zero if it
1350
 *          does not exist.
1351
 */
1352
size_t as_area_get_size(uintptr_t base)
1329 palkovsky 1353
{
1354
    ipl_t ipl;
1355
    as_area_t *src_area;
1356
    size_t size;
1357
 
1358
    ipl = interrupts_disable();
1359
    src_area = find_area_and_lock(AS, base);
1360
    if (src_area){
1361
        size = src_area->pages * PAGE_SIZE;
1380 jermar 1362
        mutex_unlock(&src_area->lock);
1329 palkovsky 1363
    } else {
1364
        size = 0;
1365
    }
1366
    interrupts_restore(ipl);
1367
    return size;
1368
}
1369
 
1387 jermar 1370
/** Mark portion of address space area as used.
1371
 *
1372
 * The address space area must be already locked.
1373
 *
1374
 * @param a Address space area.
1375
 * @param page First page to be marked.
1376
 * @param count Number of page to be marked.
1377
 *
1378
 * @return 0 on failure and 1 on success.
1379
 */
1780 jermar 1380
int used_space_insert(as_area_t *a, uintptr_t page, count_t count)
1387 jermar 1381
{
1382
    btree_node_t *leaf, *node;
1383
    count_t pages;
2745 decky 1384
    unsigned int i;
1387 jermar 1385
 
1386
    ASSERT(page == ALIGN_DOWN(page, PAGE_SIZE));
1387
    ASSERT(count);
1388
 
1389
    pages = (count_t) btree_search(&a->used_space, page, &leaf);
1390
    if (pages) {
1391
        /*
1392
         * We hit the beginning of some used space.
1393
         */
1394
        return 0;
1395
    }
1396
 
1437 jermar 1397
    if (!leaf->keys) {
1398
        btree_insert(&a->used_space, page, (void *) count, leaf);
1399
        return 1;
1400
    }
1401
 
1387 jermar 1402
    node = btree_leaf_node_left_neighbour(&a->used_space, leaf);
1403
    if (node) {
2087 jermar 1404
        uintptr_t left_pg = node->key[node->keys - 1];
1405
        uintptr_t right_pg = leaf->key[0];
1406
        count_t left_cnt = (count_t) node->value[node->keys - 1];
1407
        count_t right_cnt = (count_t) leaf->value[0];
1387 jermar 1408
 
1409
        /*
1410
         * Examine the possibility that the interval fits
1411
         * somewhere between the rightmost interval of
1412
         * the left neigbour and the first interval of the leaf.
1413
         */
1414
 
1415
        if (page >= right_pg) {
1416
            /* Do nothing. */
2087 jermar 1417
        } else if (overlaps(page, count * PAGE_SIZE, left_pg,
1418
            left_cnt * PAGE_SIZE)) {
1387 jermar 1419
            /* The interval intersects with the left interval. */
1420
            return 0;
2087 jermar 1421
        } else if (overlaps(page, count * PAGE_SIZE, right_pg,
1422
            right_cnt * PAGE_SIZE)) {
1387 jermar 1423
            /* The interval intersects with the right interval. */
1424
            return 0;          
2087 jermar 1425
        } else if ((page == left_pg + left_cnt * PAGE_SIZE) &&
1426
            (page + count * PAGE_SIZE == right_pg)) {
1427
            /*
1428
             * The interval can be added by merging the two already
1429
             * present intervals.
1430
             */
1403 jermar 1431
            node->value[node->keys - 1] += count + right_cnt;
1387 jermar 1432
            btree_remove(&a->used_space, right_pg, leaf);
1433
            return 1;
2087 jermar 1434
        } else if (page == left_pg + left_cnt * PAGE_SIZE) {
1435
            /*
1436
             * The interval can be added by simply growing the left
1437
             * interval.
1438
             */
1403 jermar 1439
            node->value[node->keys - 1] += count;
1387 jermar 1440
            return 1;
2087 jermar 1441
        } else if (page + count * PAGE_SIZE == right_pg) {
1387 jermar 1442
            /*
2087 jermar 1443
             * The interval can be addded by simply moving base of
1444
             * the right interval down and increasing its size
1445
             * accordingly.
1387 jermar 1446
             */
1403 jermar 1447
            leaf->value[0] += count;
1387 jermar 1448
            leaf->key[0] = page;
1449
            return 1;
1450
        } else {
1451
            /*
1452
             * The interval is between both neigbouring intervals,
1453
             * but cannot be merged with any of them.
1454
             */
2087 jermar 1455
            btree_insert(&a->used_space, page, (void *) count,
1456
                leaf);
1387 jermar 1457
            return 1;
1458
        }
1459
    } else if (page < leaf->key[0]) {
1780 jermar 1460
        uintptr_t right_pg = leaf->key[0];
1387 jermar 1461
        count_t right_cnt = (count_t) leaf->value[0];
1462
 
1463
        /*
2087 jermar 1464
         * Investigate the border case in which the left neighbour does
1465
         * not exist but the interval fits from the left.
1387 jermar 1466
         */
1467
 
2087 jermar 1468
        if (overlaps(page, count * PAGE_SIZE, right_pg,
1469
            right_cnt * PAGE_SIZE)) {
1387 jermar 1470
            /* The interval intersects with the right interval. */
1471
            return 0;
2087 jermar 1472
        } else if (page + count * PAGE_SIZE == right_pg) {
1387 jermar 1473
            /*
2087 jermar 1474
             * The interval can be added by moving the base of the
1475
             * right interval down and increasing its size
1476
             * accordingly.
1387 jermar 1477
             */
1478
            leaf->key[0] = page;
1403 jermar 1479
            leaf->value[0] += count;
1387 jermar 1480
            return 1;
1481
        } else {
1482
            /*
1483
             * The interval doesn't adjoin with the right interval.
1484
             * It must be added individually.
1485
             */
2087 jermar 1486
            btree_insert(&a->used_space, page, (void *) count,
1487
                leaf);
1387 jermar 1488
            return 1;
1489
        }
1490
    }
1491
 
1492
    node = btree_leaf_node_right_neighbour(&a->used_space, leaf);
1493
    if (node) {
2087 jermar 1494
        uintptr_t left_pg = leaf->key[leaf->keys - 1];
1495
        uintptr_t right_pg = node->key[0];
1496
        count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
1497
        count_t right_cnt = (count_t) node->value[0];
1387 jermar 1498
 
1499
        /*
1500
         * Examine the possibility that the interval fits
1501
         * somewhere between the leftmost interval of
1502
         * the right neigbour and the last interval of the leaf.
1503
         */
1504
 
1505
        if (page < left_pg) {
1506
            /* Do nothing. */
2087 jermar 1507
        } else if (overlaps(page, count * PAGE_SIZE, left_pg,
1508
            left_cnt * PAGE_SIZE)) {
1387 jermar 1509
            /* The interval intersects with the left interval. */
1510
            return 0;
2087 jermar 1511
        } else if (overlaps(page, count * PAGE_SIZE, right_pg,
1512
            right_cnt * PAGE_SIZE)) {
1387 jermar 1513
            /* The interval intersects with the right interval. */
1514
            return 0;          
2087 jermar 1515
        } else if ((page == left_pg + left_cnt * PAGE_SIZE) &&
1516
            (page + count * PAGE_SIZE == right_pg)) {
1517
            /*
1518
             * The interval can be added by merging the two already
1519
             * present intervals.
1520
             * */
1403 jermar 1521
            leaf->value[leaf->keys - 1] += count + right_cnt;
1387 jermar 1522
            btree_remove(&a->used_space, right_pg, node);
1523
            return 1;
2087 jermar 1524
        } else if (page == left_pg + left_cnt * PAGE_SIZE) {
1525
            /*
1526
             * The interval can be added by simply growing the left
1527
             * interval.
1528
             * */
1403 jermar 1529
            leaf->value[leaf->keys - 1] +=  count;
1387 jermar 1530
            return 1;
2087 jermar 1531
        } else if (page + count * PAGE_SIZE == right_pg) {
1387 jermar 1532
            /*
2087 jermar 1533
             * The interval can be addded by simply moving base of
1534
             * the right interval down and increasing its size
1535
             * accordingly.
1387 jermar 1536
             */
1403 jermar 1537
            node->value[0] += count;
1387 jermar 1538
            node->key[0] = page;
1539
            return 1;
1540
        } else {
1541
            /*
1542
             * The interval is between both neigbouring intervals,
1543
             * but cannot be merged with any of them.
1544
             */
2087 jermar 1545
            btree_insert(&a->used_space, page, (void *) count,
1546
                leaf);
1387 jermar 1547
            return 1;
1548
        }
1549
    } else if (page >= leaf->key[leaf->keys - 1]) {
1780 jermar 1550
        uintptr_t left_pg = leaf->key[leaf->keys - 1];
1387 jermar 1551
        count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
1552
 
1553
        /*
2087 jermar 1554
         * Investigate the border case in which the right neighbour
1555
         * does not exist but the interval fits from the right.
1387 jermar 1556
         */
1557
 
2087 jermar 1558
        if (overlaps(page, count * PAGE_SIZE, left_pg,
1559
            left_cnt * PAGE_SIZE)) {
1403 jermar 1560
            /* The interval intersects with the left interval. */
1387 jermar 1561
            return 0;
2087 jermar 1562
        } else if (left_pg + left_cnt * PAGE_SIZE == page) {
1563
            /*
1564
             * The interval can be added by growing the left
1565
             * interval.
1566
             */
1403 jermar 1567
            leaf->value[leaf->keys - 1] += count;
1387 jermar 1568
            return 1;
1569
        } else {
1570
            /*
1571
             * The interval doesn't adjoin with the left interval.
1572
             * It must be added individually.
1573
             */
2087 jermar 1574
            btree_insert(&a->used_space, page, (void *) count,
1575
                leaf);
1387 jermar 1576
            return 1;
1577
        }
1578
    }
1579
 
1580
    /*
2087 jermar 1581
     * Note that if the algorithm made it thus far, the interval can fit
1582
     * only between two other intervals of the leaf. The two border cases
1583
     * were already resolved.
1387 jermar 1584
     */
1585
    for (i = 1; i < leaf->keys; i++) {
1586
        if (page < leaf->key[i]) {
2087 jermar 1587
            uintptr_t left_pg = leaf->key[i - 1];
1588
            uintptr_t right_pg = leaf->key[i];
1589
            count_t left_cnt = (count_t) leaf->value[i - 1];
1590
            count_t right_cnt = (count_t) leaf->value[i];
1387 jermar 1591
 
1592
            /*
1593
             * The interval fits between left_pg and right_pg.
1594
             */
1595
 
2087 jermar 1596
            if (overlaps(page, count * PAGE_SIZE, left_pg,
1597
                left_cnt * PAGE_SIZE)) {
1598
                /*
1599
                 * The interval intersects with the left
1600
                 * interval.
1601
                 */
1387 jermar 1602
                return 0;
2087 jermar 1603
            } else if (overlaps(page, count * PAGE_SIZE, right_pg,
1604
                right_cnt * PAGE_SIZE)) {
1605
                /*
1606
                 * The interval intersects with the right
1607
                 * interval.
1608
                 */
1387 jermar 1609
                return 0;          
2087 jermar 1610
            } else if ((page == left_pg + left_cnt * PAGE_SIZE) &&
1611
                (page + count * PAGE_SIZE == right_pg)) {
1612
                /*
1613
                 * The interval can be added by merging the two
1614
                 * already present intervals.
1615
                 */
1403 jermar 1616
                leaf->value[i - 1] += count + right_cnt;
1387 jermar 1617
                btree_remove(&a->used_space, right_pg, leaf);
1618
                return 1;
2087 jermar 1619
            } else if (page == left_pg + left_cnt * PAGE_SIZE) {
1620
                /*
1621
                 * The interval can be added by simply growing
1622
                 * the left interval.
1623
                 */
1403 jermar 1624
                leaf->value[i - 1] += count;
1387 jermar 1625
                return 1;
2087 jermar 1626
            } else if (page + count * PAGE_SIZE == right_pg) {
1387 jermar 1627
                /*
2087 jermar 1628
                     * The interval can be addded by simply moving
1629
                 * base of the right interval down and
1630
                 * increasing its size accordingly.
1387 jermar 1631
                 */
1403 jermar 1632
                leaf->value[i] += count;
1387 jermar 1633
                leaf->key[i] = page;
1634
                return 1;
1635
            } else {
1636
                /*
2087 jermar 1637
                 * The interval is between both neigbouring
1638
                 * intervals, but cannot be merged with any of
1639
                 * them.
1387 jermar 1640
                 */
2087 jermar 1641
                btree_insert(&a->used_space, page,
1642
                    (void *) count, leaf);
1387 jermar 1643
                return 1;
1644
            }
1645
        }
1646
    }
1647
 
3057 decky 1648
    panic("Inconsistency detected while adding %" PRIc " pages of used space at "
2087 jermar 1649
        "%p.\n", count, page);
1387 jermar 1650
}
1651
 
1652
/** Mark portion of address space area as unused.
1653
 *
1654
 * The address space area must be already locked.
1655
 *
1656
 * @param a Address space area.
1657
 * @param page First page to be marked.
1658
 * @param count Number of page to be marked.
1659
 *
1660
 * @return 0 on failure and 1 on success.
1661
 */
1780 jermar 1662
int used_space_remove(as_area_t *a, uintptr_t page, count_t count)
1387 jermar 1663
{
1664
    btree_node_t *leaf, *node;
1665
    count_t pages;
2745 decky 1666
    unsigned int i;
1387 jermar 1667
 
1668
    ASSERT(page == ALIGN_DOWN(page, PAGE_SIZE));
1669
    ASSERT(count);
1670
 
1671
    pages = (count_t) btree_search(&a->used_space, page, &leaf);
1672
    if (pages) {
1673
        /*
1674
         * We are lucky, page is the beginning of some interval.
1675
         */
1676
        if (count > pages) {
1677
            return 0;
1678
        } else if (count == pages) {
1679
            btree_remove(&a->used_space, page, leaf);
1403 jermar 1680
            return 1;
1387 jermar 1681
        } else {
1682
            /*
1683
             * Find the respective interval.
1684
             * Decrease its size and relocate its start address.
1685
             */
1686
            for (i = 0; i < leaf->keys; i++) {
1687
                if (leaf->key[i] == page) {
2087 jermar 1688
                    leaf->key[i] += count * PAGE_SIZE;
1403 jermar 1689
                    leaf->value[i] -= count;
1387 jermar 1690
                    return 1;
1691
                }
1692
            }
1693
            goto error;
1694
        }
1695
    }
1696
 
1697
    node = btree_leaf_node_left_neighbour(&a->used_space, leaf);
1698
    if (node && page < leaf->key[0]) {
1780 jermar 1699
        uintptr_t left_pg = node->key[node->keys - 1];
1387 jermar 1700
        count_t left_cnt = (count_t) node->value[node->keys - 1];
1701
 
2087 jermar 1702
        if (overlaps(left_pg, left_cnt * PAGE_SIZE, page,
1703
            count * PAGE_SIZE)) {
1704
            if (page + count * PAGE_SIZE ==
1705
                left_pg + left_cnt * PAGE_SIZE) {
1387 jermar 1706
                /*
2087 jermar 1707
                 * The interval is contained in the rightmost
1708
                 * interval of the left neighbour and can be
1709
                 * removed by updating the size of the bigger
1710
                 * interval.
1387 jermar 1711
                 */
1403 jermar 1712
                node->value[node->keys - 1] -= count;
1387 jermar 1713
                return 1;
2087 jermar 1714
            } else if (page + count * PAGE_SIZE <
1715
                left_pg + left_cnt*PAGE_SIZE) {
1403 jermar 1716
                count_t new_cnt;
1387 jermar 1717
 
1718
                /*
2087 jermar 1719
                 * The interval is contained in the rightmost
1720
                 * interval of the left neighbour but its
1721
                 * removal requires both updating the size of
1722
                 * the original interval and also inserting a
1723
                 * new interval.
1387 jermar 1724
                 */
2087 jermar 1725
                new_cnt = ((left_pg + left_cnt * PAGE_SIZE) -
1726
                    (page + count*PAGE_SIZE)) >> PAGE_WIDTH;
1403 jermar 1727
                node->value[node->keys - 1] -= count + new_cnt;
2087 jermar 1728
                btree_insert(&a->used_space, page +
1729
                    count * PAGE_SIZE, (void *) new_cnt, leaf);
1387 jermar 1730
                return 1;
1731
            }
1732
        }
1733
        return 0;
1734
    } else if (page < leaf->key[0]) {
1735
        return 0;
1736
    }
1737
 
1738
    if (page > leaf->key[leaf->keys - 1]) {
1780 jermar 1739
        uintptr_t left_pg = leaf->key[leaf->keys - 1];
1387 jermar 1740
        count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
1741
 
2087 jermar 1742
        if (overlaps(left_pg, left_cnt * PAGE_SIZE, page,
1743
            count * PAGE_SIZE)) {
1744
            if (page + count * PAGE_SIZE ==
1745
                left_pg + left_cnt * PAGE_SIZE) {
1387 jermar 1746
                /*
2087 jermar 1747
                 * The interval is contained in the rightmost
1748
                 * interval of the leaf and can be removed by
1749
                 * updating the size of the bigger interval.
1387 jermar 1750
                 */
1403 jermar 1751
                leaf->value[leaf->keys - 1] -= count;
1387 jermar 1752
                return 1;
2087 jermar 1753
            } else if (page + count * PAGE_SIZE < left_pg +
1754
                left_cnt * PAGE_SIZE) {
1403 jermar 1755
                count_t new_cnt;
1387 jermar 1756
 
1757
                /*
2087 jermar 1758
                 * The interval is contained in the rightmost
1759
                 * interval of the leaf but its removal
1760
                 * requires both updating the size of the
1761
                 * original interval and also inserting a new
1762
                 * interval.
1387 jermar 1763
                 */
2087 jermar 1764
                new_cnt = ((left_pg + left_cnt * PAGE_SIZE) -
1765
                    (page + count * PAGE_SIZE)) >> PAGE_WIDTH;
1403 jermar 1766
                leaf->value[leaf->keys - 1] -= count + new_cnt;
2087 jermar 1767
                btree_insert(&a->used_space, page +
1768
                    count * PAGE_SIZE, (void *) new_cnt, leaf);
1387 jermar 1769
                return 1;
1770
            }
1771
        }
1772
        return 0;
1773
    }  
1774
 
1775
    /*
1776
     * The border cases have been already resolved.
1777
     * Now the interval can be only between intervals of the leaf.
1778
     */
1779
    for (i = 1; i < leaf->keys - 1; i++) {
1780
        if (page < leaf->key[i]) {
1780 jermar 1781
            uintptr_t left_pg = leaf->key[i - 1];
1387 jermar 1782
            count_t left_cnt = (count_t) leaf->value[i - 1];
1783
 
1784
            /*
2087 jermar 1785
             * Now the interval is between intervals corresponding
1786
             * to (i - 1) and i.
1387 jermar 1787
             */
2087 jermar 1788
            if (overlaps(left_pg, left_cnt * PAGE_SIZE, page,
1789
                count * PAGE_SIZE)) {
1790
                if (page + count * PAGE_SIZE ==
1791
                    left_pg + left_cnt*PAGE_SIZE) {
1387 jermar 1792
                    /*
2087 jermar 1793
                     * The interval is contained in the
1794
                     * interval (i - 1) of the leaf and can
1795
                     * be removed by updating the size of
1796
                     * the bigger interval.
1387 jermar 1797
                     */
1403 jermar 1798
                    leaf->value[i - 1] -= count;
1387 jermar 1799
                    return 1;
2087 jermar 1800
                } else if (page + count * PAGE_SIZE <
1801
                    left_pg + left_cnt * PAGE_SIZE) {
1403 jermar 1802
                    count_t new_cnt;
1387 jermar 1803
 
1804
                    /*
2087 jermar 1805
                     * The interval is contained in the
1806
                     * interval (i - 1) of the leaf but its
1807
                     * removal requires both updating the
1808
                     * size of the original interval and
1387 jermar 1809
                     * also inserting a new interval.
1810
                     */
2087 jermar 1811
                    new_cnt = ((left_pg +
1812
                        left_cnt * PAGE_SIZE) -
1813
                        (page + count * PAGE_SIZE)) >>
1814
                        PAGE_WIDTH;
1403 jermar 1815
                    leaf->value[i - 1] -= count + new_cnt;
2087 jermar 1816
                    btree_insert(&a->used_space, page +
1817
                        count * PAGE_SIZE, (void *) new_cnt,
1818
                        leaf);
1387 jermar 1819
                    return 1;
1820
                }
1821
            }
1822
            return 0;
1823
        }
1824
    }
1825
 
1826
error:
3057 decky 1827
    panic("Inconsistency detected while removing %" PRIc " pages of used space "
2087 jermar 1828
        "from %p.\n", count, page);
1387 jermar 1829
}
1830
 
1409 jermar 1831
/** Remove reference to address space area share info.
1832
 *
1833
 * If the reference count drops to 0, the sh_info is deallocated.
1834
 *
1835
 * @param sh_info Pointer to address space area share info.
1836
 */
1837
void sh_info_remove_reference(share_info_t *sh_info)
1838
{
1839
    bool dealloc = false;
1840
 
1841
    mutex_lock(&sh_info->lock);
1842
    ASSERT(sh_info->refcount);
1843
    if (--sh_info->refcount == 0) {
1844
        dealloc = true;
1495 jermar 1845
        link_t *cur;
1409 jermar 1846
 
1847
        /*
1848
         * Now walk carefully the pagemap B+tree and free/remove
1849
         * reference from all frames found there.
1850
         */
2087 jermar 1851
        for (cur = sh_info->pagemap.leaf_head.next;
1852
            cur != &sh_info->pagemap.leaf_head; cur = cur->next) {
1409 jermar 1853
            btree_node_t *node;
2745 decky 1854
            unsigned int i;
1409 jermar 1855
 
1495 jermar 1856
            node = list_get_instance(cur, btree_node_t, leaf_link);
1857
            for (i = 0; i < node->keys; i++)
1780 jermar 1858
                frame_free((uintptr_t) node->value[i]);
1409 jermar 1859
        }
1860
 
1861
    }
1862
    mutex_unlock(&sh_info->lock);
1863
 
1864
    if (dealloc) {
1865
        btree_destroy(&sh_info->pagemap);
1866
        free(sh_info);
1867
    }
1868
}
1869
 
1235 jermar 1870
/*
1871
 * Address space related syscalls.
1872
 */
1873
 
1874
/** Wrapper for as_area_create(). */
1780 jermar 1875
unative_t sys_as_area_create(uintptr_t address, size_t size, int flags)
1235 jermar 1876
{
2087 jermar 1877
    if (as_area_create(AS, flags | AS_AREA_CACHEABLE, size, address,
1878
        AS_AREA_ATTR_NONE, &anon_backend, NULL))
1780 jermar 1879
        return (unative_t) address;
1235 jermar 1880
    else
1780 jermar 1881
        return (unative_t) -1;
1235 jermar 1882
}
1883
 
1793 jermar 1884
/** Wrapper for as_area_resize(). */
1780 jermar 1885
unative_t sys_as_area_resize(uintptr_t address, size_t size, int flags)
1235 jermar 1886
{
1780 jermar 1887
    return (unative_t) as_area_resize(AS, address, size, 0);
1235 jermar 1888
}
1889
 
3222 svoboda 1890
/** Wrapper for as_area_change_flags(). */
1891
unative_t sys_as_area_change_flags(uintptr_t address, int flags)
1892
{
1893
    return (unative_t) as_area_change_flags(AS, flags, address);
1894
}
1895
 
1793 jermar 1896
/** Wrapper for as_area_destroy(). */
1780 jermar 1897
unative_t sys_as_area_destroy(uintptr_t address)
1306 jermar 1898
{
1780 jermar 1899
    return (unative_t) as_area_destroy(AS, address);
1306 jermar 1900
}
1702 cejka 1901
 
1914 jermar 1902
/** Print out information about address space.
1903
 *
1904
 * @param as Address space.
1905
 */
1906
void as_print(as_t *as)
1907
{
1908
    ipl_t ipl;
1909
 
1910
    ipl = interrupts_disable();
1911
    mutex_lock(&as->lock);
1912
 
1913
    /* print out info about address space areas */
1914
    link_t *cur;
2087 jermar 1915
    for (cur = as->as_area_btree.leaf_head.next;
1916
        cur != &as->as_area_btree.leaf_head; cur = cur->next) {
1917
        btree_node_t *node;
1914 jermar 1918
 
2087 jermar 1919
        node = list_get_instance(cur, btree_node_t, leaf_link);
1920
 
2745 decky 1921
        unsigned int i;
1914 jermar 1922
        for (i = 0; i < node->keys; i++) {
1915 jermar 1923
            as_area_t *area = node->value[i];
1914 jermar 1924
 
1925
            mutex_lock(&area->lock);
3057 decky 1926
            printf("as_area: %p, base=%p, pages=%" PRIc " (%p - %p)\n",
2087 jermar 1927
                area, area->base, area->pages, area->base,
3057 decky 1928
                area->base + FRAMES2SIZE(area->pages));
1914 jermar 1929
            mutex_unlock(&area->lock);
1930
        }
1931
    }
1932
 
1933
    mutex_unlock(&as->lock);
1934
    interrupts_restore(ipl);
1935
}
1936
 
1757 jermar 1937
/** @}
1702 cejka 1938
 */