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703 jermar 1
/*
2071 jermar 2
 * Copyright (c) 2001-2006 Jakub Jermar
703 jermar 3
 * All rights reserved.
4
 *
5
 * Redistribution and use in source and binary forms, with or without
6
 * modification, are permitted provided that the following conditions
7
 * are met:
8
 *
9
 * - Redistributions of source code must retain the above copyright
10
 *   notice, this list of conditions and the following disclaimer.
11
 * - Redistributions in binary form must reproduce the above copyright
12
 *   notice, this list of conditions and the following disclaimer in the
13
 *   documentation and/or other materials provided with the distribution.
14
 * - The name of the author may not be used to endorse or promote products
15
 *   derived from this software without specific prior written permission.
16
 *
17
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
 */
28
 
1757 jermar 29
/** @addtogroup genericmm
1702 cejka 30
 * @{
31
 */
32
 
1248 jermar 33
/**
1702 cejka 34
 * @file
1248 jermar 35
 * @brief   Address space related functions.
36
 *
703 jermar 37
 * This file contains address space manipulation functions.
38
 * Roughly speaking, this is a higher-level client of
39
 * Virtual Address Translation (VAT) subsystem.
1248 jermar 40
 *
41
 * Functionality provided by this file allows one to
1757 jermar 42
 * create address spaces and create, resize and share
1248 jermar 43
 * address space areas.
44
 *
45
 * @see page.c
46
 *
703 jermar 47
 */
48
 
49
#include <mm/as.h>
756 jermar 50
#include <arch/mm/as.h>
703 jermar 51
#include <mm/page.h>
52
#include <mm/frame.h>
814 palkovsky 53
#include <mm/slab.h>
703 jermar 54
#include <mm/tlb.h>
55
#include <arch/mm/page.h>
56
#include <genarch/mm/page_pt.h>
1108 jermar 57
#include <genarch/mm/page_ht.h>
727 jermar 58
#include <mm/asid.h>
703 jermar 59
#include <arch/mm/asid.h>
2183 jermar 60
#include <preemption.h>
703 jermar 61
#include <synch/spinlock.h>
1380 jermar 62
#include <synch/mutex.h>
788 jermar 63
#include <adt/list.h>
1147 jermar 64
#include <adt/btree.h>
1235 jermar 65
#include <proc/task.h>
1288 jermar 66
#include <proc/thread.h>
1235 jermar 67
#include <arch/asm.h>
703 jermar 68
#include <panic.h>
69
#include <debug.h>
1235 jermar 70
#include <print.h>
703 jermar 71
#include <memstr.h>
1070 jermar 72
#include <macros.h>
703 jermar 73
#include <arch.h>
1235 jermar 74
#include <errno.h>
75
#include <config.h>
1387 jermar 76
#include <align.h>
1235 jermar 77
#include <arch/types.h>
1288 jermar 78
#include <syscall/copy.h>
79
#include <arch/interrupt.h>
703 jermar 80
 
2009 jermar 81
#ifdef CONFIG_VIRT_IDX_DCACHE
82
#include <arch/mm/cache.h>
83
#endif /* CONFIG_VIRT_IDX_DCACHE */
84
 
1757 jermar 85
/**
86
 * Each architecture decides what functions will be used to carry out
87
 * address space operations such as creating or locking page tables.
88
 */
756 jermar 89
as_operations_t *as_operations = NULL;
703 jermar 90
 
1890 jermar 91
/**
92
 * Slab for as_t objects.
93
 */
94
static slab_cache_t *as_slab;
95
 
2087 jermar 96
/**
2170 jermar 97
 * This lock serializes access to the ASID subsystem.
98
 * It protects:
99
 * - inactive_as_with_asid_head list
100
 * - as->asid for each as of the as_t type
101
 * - asids_allocated counter
2087 jermar 102
 */
2170 jermar 103
SPINLOCK_INITIALIZE(asidlock);
823 jermar 104
 
105
/**
106
 * This list contains address spaces that are not active on any
107
 * processor and that have valid ASID.
108
 */
109
LIST_INITIALIZE(inactive_as_with_asid_head);
110
 
757 jermar 111
/** Kernel address space. */
112
as_t *AS_KERNEL = NULL;
113
 
3425 svoboda 114
static int area_flags_to_page_flags(int);
115
static bool check_area_conflicts(as_t *, uintptr_t, size_t, as_area_t *);
116
static void sh_info_remove_reference(share_info_t *);
703 jermar 117
 
1891 jermar 118
static int as_constructor(void *obj, int flags)
119
{
120
    as_t *as = (as_t *) obj;
121
    int rc;
122
 
123
    link_initialize(&as->inactive_as_with_asid_link);
3425 svoboda 124
    mutex_initialize(&as->lock, MUTEX_PASSIVE);
1891 jermar 125
 
126
    rc = as_constructor_arch(as, flags);
127
 
128
    return rc;
129
}
130
 
131
static int as_destructor(void *obj)
132
{
133
    as_t *as = (as_t *) obj;
134
 
135
    return as_destructor_arch(as);
136
}
137
 
756 jermar 138
/** Initialize address space subsystem. */
139
void as_init(void)
140
{
141
    as_arch_init();
2126 decky 142
 
1891 jermar 143
    as_slab = slab_cache_create("as_slab", sizeof(as_t), 0,
2087 jermar 144
        as_constructor, as_destructor, SLAB_CACHE_MAGDEFERRED);
1890 jermar 145
 
789 palkovsky 146
    AS_KERNEL = as_create(FLAG_AS_KERNEL);
1383 decky 147
    if (!AS_KERNEL)
148
        panic("can't create kernel address space\n");
149
 
756 jermar 150
}
151
 
757 jermar 152
/** Create address space.
153
 *
3425 svoboda 154
 * @param flags     Flags that influence the way in wich the address space
155
 *          is created.
757 jermar 156
 */
756 jermar 157
as_t *as_create(int flags)
703 jermar 158
{
159
    as_t *as;
160
 
1890 jermar 161
    as = (as_t *) slab_alloc(as_slab, 0);
1891 jermar 162
    (void) as_create_arch(as, 0);
163
 
1147 jermar 164
    btree_create(&as->as_area_btree);
822 palkovsky 165
 
166
    if (flags & FLAG_AS_KERNEL)
167
        as->asid = ASID_KERNEL;
168
    else
169
        as->asid = ASID_INVALID;
170
 
2183 jermar 171
    atomic_set(&as->refcount, 0);
1415 jermar 172
    as->cpu_refcount = 0;
2089 decky 173
#ifdef AS_PAGE_TABLE
2106 jermar 174
    as->genarch.page_table = page_table_create(flags);
2089 decky 175
#else
176
    page_table_create(flags);
177
#endif
703 jermar 178
 
179
    return as;
180
}
181
 
1468 jermar 182
/** Destroy adress space.
183
 *
2087 jermar 184
 * When there are no tasks referencing this address space (i.e. its refcount is
185
 * zero), the address space can be destroyed.
2183 jermar 186
 *
187
 * We know that we don't hold any spinlock.
3425 svoboda 188
 *
189
 * @param as        Address space to be destroyed.
1468 jermar 190
 */
191
void as_destroy(as_t *as)
973 palkovsky 192
{
1468 jermar 193
    ipl_t ipl;
1594 jermar 194
    bool cond;
2183 jermar 195
    DEADLOCK_PROBE_INIT(p_asidlock);
973 palkovsky 196
 
2183 jermar 197
    ASSERT(atomic_get(&as->refcount) == 0);
1468 jermar 198
 
199
    /*
200
     * Since there is no reference to this area,
201
     * it is safe not to lock its mutex.
202
     */
2170 jermar 203
 
2183 jermar 204
    /*
205
     * We need to avoid deadlock between TLB shootdown and asidlock.
206
     * We therefore try to take asid conditionally and if we don't succeed,
207
     * we enable interrupts and try again. This is done while preemption is
208
     * disabled to prevent nested context switches. We also depend on the
209
     * fact that so far no spinlocks are held.
210
     */
211
    preemption_disable();
212
    ipl = interrupts_read();
213
retry:
214
    interrupts_disable();
215
    if (!spinlock_trylock(&asidlock)) {
216
        interrupts_enable();
217
        DEADLOCK_PROBE(p_asidlock, DEADLOCK_THRESHOLD);
218
        goto retry;
219
    }
220
    preemption_enable();    /* Interrupts disabled, enable preemption */
1587 jermar 221
    if (as->asid != ASID_INVALID && as != AS_KERNEL) {
1594 jermar 222
        if (as != AS && as->cpu_refcount == 0)
1587 jermar 223
            list_remove(&as->inactive_as_with_asid_link);
1468 jermar 224
        asid_put(as->asid);
225
    }
2170 jermar 226
    spinlock_unlock(&asidlock);
1468 jermar 227
 
228
    /*
229
     * Destroy address space areas of the address space.
1954 jermar 230
     * The B+tree must be walked carefully because it is
1594 jermar 231
     * also being destroyed.
1468 jermar 232
     */
1594 jermar 233
    for (cond = true; cond; ) {
1468 jermar 234
        btree_node_t *node;
1594 jermar 235
 
236
        ASSERT(!list_empty(&as->as_area_btree.leaf_head));
2087 jermar 237
        node = list_get_instance(as->as_area_btree.leaf_head.next,
238
            btree_node_t, leaf_link);
1594 jermar 239
 
240
        if ((cond = node->keys)) {
241
            as_area_destroy(as, node->key[0]);
242
        }
1468 jermar 243
    }
1495 jermar 244
 
1483 jermar 245
    btree_destroy(&as->as_area_btree);
2089 decky 246
#ifdef AS_PAGE_TABLE
2106 jermar 247
    page_table_destroy(as->genarch.page_table);
2089 decky 248
#else
249
    page_table_destroy(NULL);
250
#endif
1468 jermar 251
 
252
    interrupts_restore(ipl);
2126 decky 253
 
1890 jermar 254
    slab_free(as_slab, as);
973 palkovsky 255
}
256
 
703 jermar 257
/** Create address space area of common attributes.
258
 *
259
 * The created address space area is added to the target address space.
260
 *
3425 svoboda 261
 * @param as        Target address space.
262
 * @param flags     Flags of the area memory.
263
 * @param size      Size of area.
264
 * @param base      Base address of area.
265
 * @param attrs     Attributes of the area.
266
 * @param backend   Address space area backend. NULL if no backend is used.
267
 * @param backend_data  NULL or a pointer to an array holding two void *.
703 jermar 268
 *
3425 svoboda 269
 * @return      Address space area on success or NULL on failure.
703 jermar 270
 */
2069 jermar 271
as_area_t *
272
as_area_create(as_t *as, int flags, size_t size, uintptr_t base, int attrs,
3425 svoboda 273
    mem_backend_t *backend, mem_backend_data_t *backend_data)
703 jermar 274
{
275
    ipl_t ipl;
276
    as_area_t *a;
277
 
278
    if (base % PAGE_SIZE)
1048 jermar 279
        return NULL;
280
 
1233 jermar 281
    if (!size)
282
        return NULL;
283
 
1048 jermar 284
    /* Writeable executable areas are not supported. */
285
    if ((flags & AS_AREA_EXEC) && (flags & AS_AREA_WRITE))
286
        return NULL;
703 jermar 287
 
288
    ipl = interrupts_disable();
1380 jermar 289
    mutex_lock(&as->lock);
703 jermar 290
 
1048 jermar 291
    if (!check_area_conflicts(as, base, size, NULL)) {
1380 jermar 292
        mutex_unlock(&as->lock);
1048 jermar 293
        interrupts_restore(ipl);
294
        return NULL;
295
    }
703 jermar 296
 
822 palkovsky 297
    a = (as_area_t *) malloc(sizeof(as_area_t), 0);
703 jermar 298
 
3425 svoboda 299
    mutex_initialize(&a->lock, MUTEX_PASSIVE);
822 palkovsky 300
 
1424 jermar 301
    a->as = as;
1026 jermar 302
    a->flags = flags;
1239 jermar 303
    a->attributes = attrs;
1048 jermar 304
    a->pages = SIZE2FRAMES(size);
822 palkovsky 305
    a->base = base;
1409 jermar 306
    a->sh_info = NULL;
307
    a->backend = backend;
1424 jermar 308
    if (backend_data)
309
        a->backend_data = *backend_data;
310
    else
3424 svoboda 311
        memsetb(&a->backend_data, sizeof(a->backend_data), 0);
1424 jermar 312
 
1387 jermar 313
    btree_create(&a->used_space);
822 palkovsky 314
 
1147 jermar 315
    btree_insert(&as->as_area_btree, base, (void *) a, NULL);
822 palkovsky 316
 
1380 jermar 317
    mutex_unlock(&as->lock);
703 jermar 318
    interrupts_restore(ipl);
704 jermar 319
 
703 jermar 320
    return a;
321
}
322
 
1235 jermar 323
/** Find address space area and change it.
324
 *
3425 svoboda 325
 * @param as        Address space.
326
 * @param address   Virtual address belonging to the area to be changed.
327
 *          Must be page-aligned.
328
 * @param size      New size of the virtual memory block starting at
329
 *          address.
330
 * @param flags     Flags influencing the remap operation. Currently unused.
1235 jermar 331
 *
3425 svoboda 332
 * @return      Zero on success or a value from @ref errno.h otherwise.
1235 jermar 333
 */
1780 jermar 334
int as_area_resize(as_t *as, uintptr_t address, size_t size, int flags)
1235 jermar 335
{
1306 jermar 336
    as_area_t *area;
1235 jermar 337
    ipl_t ipl;
338
    size_t pages;
339
 
340
    ipl = interrupts_disable();
1380 jermar 341
    mutex_lock(&as->lock);
1235 jermar 342
 
343
    /*
344
     * Locate the area.
345
     */
346
    area = find_area_and_lock(as, address);
347
    if (!area) {
1380 jermar 348
        mutex_unlock(&as->lock);
1235 jermar 349
        interrupts_restore(ipl);
1306 jermar 350
        return ENOENT;
1235 jermar 351
    }
352
 
1424 jermar 353
    if (area->backend == &phys_backend) {
1235 jermar 354
        /*
355
         * Remapping of address space areas associated
356
         * with memory mapped devices is not supported.
357
         */
1380 jermar 358
        mutex_unlock(&area->lock);
359
        mutex_unlock(&as->lock);
1235 jermar 360
        interrupts_restore(ipl);
1306 jermar 361
        return ENOTSUP;
1235 jermar 362
    }
1409 jermar 363
    if (area->sh_info) {
364
        /*
365
         * Remapping of shared address space areas
366
         * is not supported.
367
         */
368
        mutex_unlock(&area->lock);
369
        mutex_unlock(&as->lock);
370
        interrupts_restore(ipl);
371
        return ENOTSUP;
372
    }
1235 jermar 373
 
374
    pages = SIZE2FRAMES((address - area->base) + size);
375
    if (!pages) {
376
        /*
377
         * Zero size address space areas are not allowed.
378
         */
1380 jermar 379
        mutex_unlock(&area->lock);
380
        mutex_unlock(&as->lock);
1235 jermar 381
        interrupts_restore(ipl);
1306 jermar 382
        return EPERM;
1235 jermar 383
    }
384
 
385
    if (pages < area->pages) {
1403 jermar 386
        bool cond;
3425 svoboda 387
        uintptr_t start_free = area->base + pages * PAGE_SIZE;
1235 jermar 388
 
389
        /*
390
         * Shrinking the area.
391
         * No need to check for overlaps.
392
         */
1403 jermar 393
 
394
        /*
1436 jermar 395
         * Start TLB shootdown sequence.
396
         */
3425 svoboda 397
        tlb_shootdown_start(TLB_INVL_PAGES, as->asid, area->base +
2087 jermar 398
            pages * PAGE_SIZE, area->pages - pages);
1436 jermar 399
 
400
        /*
1403 jermar 401
         * Remove frames belonging to used space starting from
402
         * the highest addresses downwards until an overlap with
403
         * the resized address space area is found. Note that this
404
         * is also the right way to remove part of the used_space
405
         * B+tree leaf list.
406
         */    
407
        for (cond = true; cond;) {
408
            btree_node_t *node;
409
 
410
            ASSERT(!list_empty(&area->used_space.leaf_head));
2087 jermar 411
            node =
412
                list_get_instance(area->used_space.leaf_head.prev,
413
                btree_node_t, leaf_link);
1403 jermar 414
            if ((cond = (bool) node->keys)) {
1780 jermar 415
                uintptr_t b = node->key[node->keys - 1];
2087 jermar 416
                count_t c =
417
                    (count_t) node->value[node->keys - 1];
2745 decky 418
                unsigned int i = 0;
1235 jermar 419
 
2087 jermar 420
                if (overlaps(b, c * PAGE_SIZE, area->base,
2133 jermar 421
                    pages * PAGE_SIZE)) {
1403 jermar 422
 
2087 jermar 423
                    if (b + c * PAGE_SIZE <= start_free) {
1403 jermar 424
                        /*
2087 jermar 425
                         * The whole interval fits
426
                         * completely in the resized
427
                         * address space area.
1403 jermar 428
                         */
429
                        break;
430
                    }
431
 
432
                    /*
2087 jermar 433
                     * Part of the interval corresponding
434
                     * to b and c overlaps with the resized
435
                     * address space area.
1403 jermar 436
                     */
437
 
438
                    cond = false;   /* we are almost done */
439
                    i = (start_free - b) >> PAGE_WIDTH;
3425 svoboda 440
                    if (!used_space_remove(area, start_free,
441
                        c - i))
442
                        panic("Could not remove used "
443
                            "space.\n");
1403 jermar 444
                } else {
445
                    /*
2087 jermar 446
                     * The interval of used space can be
447
                     * completely removed.
1403 jermar 448
                     */
449
                    if (!used_space_remove(area, b, c))
3425 svoboda 450
                        panic("Could not remove used "
451
                            "space.\n");
1403 jermar 452
                }
453
 
454
                for (; i < c; i++) {
455
                    pte_t *pte;
456
 
457
                    page_table_lock(as, false);
2087 jermar 458
                    pte = page_mapping_find(as, b +
459
                        i * PAGE_SIZE);
460
                    ASSERT(pte && PTE_VALID(pte) &&
461
                        PTE_PRESENT(pte));
462
                    if (area->backend &&
463
                        area->backend->frame_free) {
1424 jermar 464
                        area->backend->frame_free(area,
2087 jermar 465
                            b + i * PAGE_SIZE,
466
                            PTE_GET_FRAME(pte));
1409 jermar 467
                    }
2087 jermar 468
                    page_mapping_remove(as, b +
469
                        i * PAGE_SIZE);
1403 jermar 470
                    page_table_unlock(as, false);
471
                }
1235 jermar 472
            }
473
        }
1436 jermar 474
 
1235 jermar 475
        /*
1436 jermar 476
         * Finish TLB shootdown sequence.
1235 jermar 477
         */
2183 jermar 478
 
2087 jermar 479
        tlb_invalidate_pages(as->asid, area->base + pages * PAGE_SIZE,
480
            area->pages - pages);
1889 jermar 481
        /*
482
         * Invalidate software translation caches (e.g. TSB on sparc64).
483
         */
2087 jermar 484
        as_invalidate_translation_cache(as, area->base +
485
            pages * PAGE_SIZE, area->pages - pages);
2183 jermar 486
        tlb_shootdown_finalize();
487
 
1235 jermar 488
    } else {
489
        /*
490
         * Growing the area.
491
         * Check for overlaps with other address space areas.
492
         */
2087 jermar 493
        if (!check_area_conflicts(as, address, pages * PAGE_SIZE,
494
            area)) {
1380 jermar 495
            mutex_unlock(&area->lock);
496
            mutex_unlock(&as->lock);       
1235 jermar 497
            interrupts_restore(ipl);
1306 jermar 498
            return EADDRNOTAVAIL;
1235 jermar 499
        }
500
    }
501
 
502
    area->pages = pages;
503
 
1380 jermar 504
    mutex_unlock(&area->lock);
505
    mutex_unlock(&as->lock);
1235 jermar 506
    interrupts_restore(ipl);
507
 
1306 jermar 508
    return 0;
1235 jermar 509
}
510
 
1306 jermar 511
/** Destroy address space area.
512
 *
3425 svoboda 513
 * @param as        Address space.
514
 * @param address   Address within the area to be deleted.
1306 jermar 515
 *
3425 svoboda 516
 * @return      Zero on success or a value from @ref errno.h on failure.
1306 jermar 517
 */
1780 jermar 518
int as_area_destroy(as_t *as, uintptr_t address)
1306 jermar 519
{
520
    as_area_t *area;
1780 jermar 521
    uintptr_t base;
1495 jermar 522
    link_t *cur;
1306 jermar 523
    ipl_t ipl;
524
 
525
    ipl = interrupts_disable();
1380 jermar 526
    mutex_lock(&as->lock);
1306 jermar 527
 
528
    area = find_area_and_lock(as, address);
529
    if (!area) {
1380 jermar 530
        mutex_unlock(&as->lock);
1306 jermar 531
        interrupts_restore(ipl);
532
        return ENOENT;
533
    }
534
 
1403 jermar 535
    base = area->base;
536
 
1411 jermar 537
    /*
1436 jermar 538
     * Start TLB shootdown sequence.
539
     */
1889 jermar 540
    tlb_shootdown_start(TLB_INVL_PAGES, as->asid, area->base, area->pages);
1436 jermar 541
 
542
    /*
1411 jermar 543
     * Visit only the pages mapped by used_space B+tree.
544
     */
2087 jermar 545
    for (cur = area->used_space.leaf_head.next;
546
        cur != &area->used_space.leaf_head; cur = cur->next) {
1411 jermar 547
        btree_node_t *node;
2745 decky 548
        unsigned int i;
1403 jermar 549
 
1495 jermar 550
        node = list_get_instance(cur, btree_node_t, leaf_link);
551
        for (i = 0; i < node->keys; i++) {
1780 jermar 552
            uintptr_t b = node->key[i];
1495 jermar 553
            count_t j;
1411 jermar 554
            pte_t *pte;
1403 jermar 555
 
1495 jermar 556
            for (j = 0; j < (count_t) node->value[i]; j++) {
1411 jermar 557
                page_table_lock(as, false);
2087 jermar 558
                pte = page_mapping_find(as, b + j * PAGE_SIZE);
559
                ASSERT(pte && PTE_VALID(pte) &&
560
                    PTE_PRESENT(pte));
561
                if (area->backend &&
562
                    area->backend->frame_free) {
563
                    area->backend->frame_free(area, b +
2133 jermar 564
                        j * PAGE_SIZE, PTE_GET_FRAME(pte));
1403 jermar 565
                }
2087 jermar 566
                page_mapping_remove(as, b + j * PAGE_SIZE);            
1411 jermar 567
                page_table_unlock(as, false);
1306 jermar 568
            }
569
        }
570
    }
1403 jermar 571
 
1306 jermar 572
    /*
1436 jermar 573
     * Finish TLB shootdown sequence.
1306 jermar 574
     */
2183 jermar 575
 
1889 jermar 576
    tlb_invalidate_pages(as->asid, area->base, area->pages);
577
    /*
2087 jermar 578
     * Invalidate potential software translation caches (e.g. TSB on
579
     * sparc64).
1889 jermar 580
     */
581
    as_invalidate_translation_cache(as, area->base, area->pages);
2183 jermar 582
    tlb_shootdown_finalize();
1889 jermar 583
 
1436 jermar 584
    btree_destroy(&area->used_space);
1306 jermar 585
 
1309 jermar 586
    area->attributes |= AS_AREA_ATTR_PARTIAL;
1409 jermar 587
 
588
    if (area->sh_info)
589
        sh_info_remove_reference(area->sh_info);
590
 
1380 jermar 591
    mutex_unlock(&area->lock);
1306 jermar 592
 
593
    /*
594
     * Remove the empty area from address space.
595
     */
1889 jermar 596
    btree_remove(&as->as_area_btree, base, NULL);
1306 jermar 597
 
1309 jermar 598
    free(area);
599
 
1889 jermar 600
    mutex_unlock(&as->lock);
1306 jermar 601
    interrupts_restore(ipl);
602
    return 0;
603
}
604
 
1413 jermar 605
/** Share address space area with another or the same address space.
1235 jermar 606
 *
1424 jermar 607
 * Address space area mapping is shared with a new address space area.
608
 * If the source address space area has not been shared so far,
609
 * a new sh_info is created. The new address space area simply gets the
610
 * sh_info of the source area. The process of duplicating the
611
 * mapping is done through the backend share function.
1413 jermar 612
 *
3425 svoboda 613
 * @param src_as    Pointer to source address space.
614
 * @param src_base  Base address of the source address space area.
615
 * @param acc_size  Expected size of the source area.
616
 * @param dst_as    Pointer to destination address space.
617
 * @param dst_base  Target base address.
1417 jermar 618
 * @param dst_flags_mask Destination address space area flags mask.
1235 jermar 619
 *
3425 svoboda 620
 * @return      Zero on success or ENOENT if there is no such task or if
621
 *          there is no such address space area, EPERM if there was
622
 *          a problem in accepting the area or ENOMEM if there was a
623
 *          problem in allocating destination address space area.
624
 *          ENOTSUP is returned if the address space area backend
625
 *          does not support sharing.
1235 jermar 626
 */
1780 jermar 627
int as_area_share(as_t *src_as, uintptr_t src_base, size_t acc_size,
2647 jermar 628
    as_t *dst_as, uintptr_t dst_base, int dst_flags_mask)
1235 jermar 629
{
630
    ipl_t ipl;
1239 jermar 631
    int src_flags;
632
    size_t src_size;
633
    as_area_t *src_area, *dst_area;
1413 jermar 634
    share_info_t *sh_info;
1424 jermar 635
    mem_backend_t *src_backend;
636
    mem_backend_data_t src_backend_data;
1434 palkovsky 637
 
1235 jermar 638
    ipl = interrupts_disable();
1380 jermar 639
    mutex_lock(&src_as->lock);
1329 palkovsky 640
    src_area = find_area_and_lock(src_as, src_base);
1239 jermar 641
    if (!src_area) {
1238 jermar 642
        /*
643
         * Could not find the source address space area.
644
         */
1380 jermar 645
        mutex_unlock(&src_as->lock);
1238 jermar 646
        interrupts_restore(ipl);
647
        return ENOENT;
648
    }
2007 jermar 649
 
1424 jermar 650
    if (!src_area->backend || !src_area->backend->share) {
1413 jermar 651
        /*
1851 jermar 652
         * There is no backend or the backend does not
1424 jermar 653
         * know how to share the area.
1413 jermar 654
         */
655
        mutex_unlock(&src_area->lock);
656
        mutex_unlock(&src_as->lock);
657
        interrupts_restore(ipl);
658
        return ENOTSUP;
659
    }
660
 
1239 jermar 661
    src_size = src_area->pages * PAGE_SIZE;
662
    src_flags = src_area->flags;
1424 jermar 663
    src_backend = src_area->backend;
664
    src_backend_data = src_area->backend_data;
1544 palkovsky 665
 
666
    /* Share the cacheable flag from the original mapping */
667
    if (src_flags & AS_AREA_CACHEABLE)
668
        dst_flags_mask |= AS_AREA_CACHEABLE;
669
 
2087 jermar 670
    if (src_size != acc_size ||
671
        (src_flags & dst_flags_mask) != dst_flags_mask) {
1413 jermar 672
        mutex_unlock(&src_area->lock);
673
        mutex_unlock(&src_as->lock);
1235 jermar 674
        interrupts_restore(ipl);
675
        return EPERM;
676
    }
1413 jermar 677
 
1235 jermar 678
    /*
1413 jermar 679
     * Now we are committed to sharing the area.
1954 jermar 680
     * First, prepare the area for sharing.
1413 jermar 681
     * Then it will be safe to unlock it.
682
     */
683
    sh_info = src_area->sh_info;
684
    if (!sh_info) {
685
        sh_info = (share_info_t *) malloc(sizeof(share_info_t), 0);
3425 svoboda 686
        mutex_initialize(&sh_info->lock, MUTEX_PASSIVE);
1413 jermar 687
        sh_info->refcount = 2;
688
        btree_create(&sh_info->pagemap);
689
        src_area->sh_info = sh_info;
2647 jermar 690
        /*
691
         * Call the backend to setup sharing.
692
         */
693
        src_area->backend->share(src_area);
1413 jermar 694
    } else {
695
        mutex_lock(&sh_info->lock);
696
        sh_info->refcount++;
697
        mutex_unlock(&sh_info->lock);
698
    }
699
 
700
    mutex_unlock(&src_area->lock);
701
    mutex_unlock(&src_as->lock);
702
 
703
    /*
1239 jermar 704
     * Create copy of the source address space area.
705
     * The destination area is created with AS_AREA_ATTR_PARTIAL
706
     * attribute set which prevents race condition with
707
     * preliminary as_page_fault() calls.
1417 jermar 708
     * The flags of the source area are masked against dst_flags_mask
709
     * to support sharing in less privileged mode.
1235 jermar 710
     */
1461 palkovsky 711
    dst_area = as_area_create(dst_as, dst_flags_mask, src_size, dst_base,
2087 jermar 712
        AS_AREA_ATTR_PARTIAL, src_backend, &src_backend_data);
1239 jermar 713
    if (!dst_area) {
1235 jermar 714
        /*
715
         * Destination address space area could not be created.
716
         */
1413 jermar 717
        sh_info_remove_reference(sh_info);
718
 
1235 jermar 719
        interrupts_restore(ipl);
720
        return ENOMEM;
721
    }
2009 jermar 722
 
1235 jermar 723
    /*
1239 jermar 724
     * Now the destination address space area has been
725
     * fully initialized. Clear the AS_AREA_ATTR_PARTIAL
1413 jermar 726
     * attribute and set the sh_info.
1239 jermar 727
     */
2009 jermar 728
    mutex_lock(&dst_as->lock); 
1380 jermar 729
    mutex_lock(&dst_area->lock);
1239 jermar 730
    dst_area->attributes &= ~AS_AREA_ATTR_PARTIAL;
1413 jermar 731
    dst_area->sh_info = sh_info;
1380 jermar 732
    mutex_unlock(&dst_area->lock);
2009 jermar 733
    mutex_unlock(&dst_as->lock);   
734
 
1235 jermar 735
    interrupts_restore(ipl);
736
 
737
    return 0;
738
}
739
 
1423 jermar 740
/** Check access mode for address space area.
741
 *
742
 * The address space area must be locked prior to this call.
743
 *
3425 svoboda 744
 * @param area      Address space area.
745
 * @param access    Access mode.
1423 jermar 746
 *
3425 svoboda 747
 * @return      False if access violates area's permissions, true
748
 *          otherwise.
1423 jermar 749
 */
750
bool as_area_check_access(as_area_t *area, pf_access_t access)
751
{
752
    int flagmap[] = {
753
        [PF_ACCESS_READ] = AS_AREA_READ,
754
        [PF_ACCESS_WRITE] = AS_AREA_WRITE,
755
        [PF_ACCESS_EXEC] = AS_AREA_EXEC
756
    };
757
 
758
    if (!(area->flags & flagmap[access]))
759
        return false;
760
 
761
    return true;
762
}
763
 
3425 svoboda 764
/** Change adress space area flags.
765
 *
766
 * The idea is to have the same data, but with a different access mode.
767
 * This is needed e.g. for writing code into memory and then executing it.
768
 * In order for this to work properly, this may copy the data
769
 * into private anonymous memory (unless it's already there).
770
 *
771
 * @param as        Address space.
772
 * @param flags     Flags of the area memory.
773
 * @param address   Address withing the area to be changed.
774
 *
775
 * @return      Zero on success or a value from @ref errno.h on failure.
776
 */
777
int as_area_change_flags(as_t *as, int flags, uintptr_t address)
778
{
779
    as_area_t *area;
780
    uintptr_t base;
781
    link_t *cur;
782
    ipl_t ipl;
783
    int page_flags;
784
    uintptr_t *old_frame;
785
    index_t frame_idx;
786
    count_t used_pages;
787
 
788
    /* Flags for the new memory mapping */
789
    page_flags = area_flags_to_page_flags(flags);
790
 
791
    ipl = interrupts_disable();
792
    mutex_lock(&as->lock);
793
 
794
    area = find_area_and_lock(as, address);
795
    if (!area) {
796
        mutex_unlock(&as->lock);
797
        interrupts_restore(ipl);
798
        return ENOENT;
799
    }
800
 
801
    if (area->sh_info || area->backend != &anon_backend) {
802
        /* Copying shared areas not supported yet */
803
        /* Copying non-anonymous memory not supported yet */
804
        mutex_unlock(&area->lock);
805
        mutex_unlock(&as->lock);
806
        interrupts_restore(ipl);
807
        return ENOTSUP;
808
    }
809
 
810
    base = area->base;
811
 
812
    /*
813
     * Compute total number of used pages in the used_space B+tree
814
     */
815
    used_pages = 0;
816
 
817
    for (cur = area->used_space.leaf_head.next;
818
        cur != &area->used_space.leaf_head; cur = cur->next) {
819
        btree_node_t *node;
820
        unsigned int i;
821
 
822
        node = list_get_instance(cur, btree_node_t, leaf_link);
823
        for (i = 0; i < node->keys; i++) {
824
            used_pages += (count_t) node->value[i];
825
        }
826
    }
827
 
828
    /* An array for storing frame numbers */
829
    old_frame = malloc(used_pages * sizeof(uintptr_t), 0);
830
 
831
    /*
832
     * Start TLB shootdown sequence.
833
     */
834
    tlb_shootdown_start(TLB_INVL_PAGES, as->asid, area->base, area->pages);
835
 
836
    /*
837
     * Remove used pages from page tables and remember their frame
838
     * numbers.
839
     */
840
    frame_idx = 0;
841
 
842
    for (cur = area->used_space.leaf_head.next;
843
        cur != &area->used_space.leaf_head; cur = cur->next) {
844
        btree_node_t *node;
845
        unsigned int i;
846
 
847
        node = list_get_instance(cur, btree_node_t, leaf_link);
848
        for (i = 0; i < node->keys; i++) {
849
            uintptr_t b = node->key[i];
850
            count_t j;
851
            pte_t *pte;
852
 
853
            for (j = 0; j < (count_t) node->value[i]; j++) {
854
                page_table_lock(as, false);
855
                pte = page_mapping_find(as, b + j * PAGE_SIZE);
856
                ASSERT(pte && PTE_VALID(pte) &&
857
                    PTE_PRESENT(pte));
858
                old_frame[frame_idx++] = PTE_GET_FRAME(pte);
859
 
860
                /* Remove old mapping */
861
                page_mapping_remove(as, b + j * PAGE_SIZE);
862
                page_table_unlock(as, false);
863
            }
864
        }
865
    }
866
 
867
    /*
868
     * Finish TLB shootdown sequence.
869
     */
870
 
871
    tlb_invalidate_pages(as->asid, area->base, area->pages);
872
    /*
873
     * Invalidate potential software translation caches (e.g. TSB on
874
     * sparc64).
875
     */
876
    as_invalidate_translation_cache(as, area->base, area->pages);
877
    tlb_shootdown_finalize();
878
 
879
    /*
880
     * Set the new flags.
881
     */
882
    area->flags = flags;
883
 
884
    /*
885
     * Map pages back in with new flags. This step is kept separate
886
     * so that the memory area could not be accesed with both the old and
887
     * the new flags at once.
888
     */
889
    frame_idx = 0;
890
 
891
    for (cur = area->used_space.leaf_head.next;
892
        cur != &area->used_space.leaf_head; cur = cur->next) {
893
        btree_node_t *node;
894
        unsigned int i;
895
 
896
        node = list_get_instance(cur, btree_node_t, leaf_link);
897
        for (i = 0; i < node->keys; i++) {
898
            uintptr_t b = node->key[i];
899
            count_t j;
900
 
901
            for (j = 0; j < (count_t) node->value[i]; j++) {
902
                page_table_lock(as, false);
903
 
904
                /* Insert the new mapping */
905
                page_mapping_insert(as, b + j * PAGE_SIZE,
906
                    old_frame[frame_idx++], page_flags);
907
 
908
                page_table_unlock(as, false);
909
            }
910
        }
911
    }
912
 
913
    free(old_frame);
914
 
915
    mutex_unlock(&area->lock);
916
    mutex_unlock(&as->lock);
917
    interrupts_restore(ipl);
918
 
919
    return 0;
920
}
921
 
922
 
703 jermar 923
/** Handle page fault within the current address space.
924
 *
3425 svoboda 925
 * This is the high-level page fault handler. It decides whether the page fault
926
 * can be resolved by any backend and if so, it invokes the backend to resolve
927
 * the page fault.
1409 jermar 928
 *
703 jermar 929
 * Interrupts are assumed disabled.
930
 *
3425 svoboda 931
 * @param page      Faulting page.
932
 * @param access    Access mode that caused the page fault (i.e.
933
 *          read/write/exec).
934
 * @param istate    Pointer to the interrupted state.
703 jermar 935
 *
3425 svoboda 936
 * @return      AS_PF_FAULT on page fault, AS_PF_OK on success or
937
 *          AS_PF_DEFER if the fault was caused by copy_to_uspace()
938
 *          or copy_from_uspace().
703 jermar 939
 */
1780 jermar 940
int as_page_fault(uintptr_t page, pf_access_t access, istate_t *istate)
703 jermar 941
{
1044 jermar 942
    pte_t *pte;
977 jermar 943
    as_area_t *area;
703 jermar 944
 
1380 jermar 945
    if (!THREAD)
1409 jermar 946
        return AS_PF_FAULT;
1380 jermar 947
 
703 jermar 948
    ASSERT(AS);
1044 jermar 949
 
1380 jermar 950
    mutex_lock(&AS->lock);
977 jermar 951
    area = find_area_and_lock(AS, page);   
703 jermar 952
    if (!area) {
953
        /*
954
         * No area contained mapping for 'page'.
955
         * Signal page fault to low-level handler.
956
         */
1380 jermar 957
        mutex_unlock(&AS->lock);
1288 jermar 958
        goto page_fault;
703 jermar 959
    }
960
 
1239 jermar 961
    if (area->attributes & AS_AREA_ATTR_PARTIAL) {
962
        /*
963
         * The address space area is not fully initialized.
964
         * Avoid possible race by returning error.
965
         */
1380 jermar 966
        mutex_unlock(&area->lock);
967
        mutex_unlock(&AS->lock);
1288 jermar 968
        goto page_fault;       
1239 jermar 969
    }
970
 
1424 jermar 971
    if (!area->backend || !area->backend->page_fault) {
1409 jermar 972
        /*
973
         * The address space area is not backed by any backend
974
         * or the backend cannot handle page faults.
975
         */
976
        mutex_unlock(&area->lock);
977
        mutex_unlock(&AS->lock);
978
        goto page_fault;       
979
    }
1179 jermar 980
 
1044 jermar 981
    page_table_lock(AS, false);
982
 
703 jermar 983
    /*
3425 svoboda 984
     * To avoid race condition between two page faults on the same address,
985
     * we need to make sure the mapping has not been already inserted.
1044 jermar 986
     */
987
    if ((pte = page_mapping_find(AS, page))) {
988
        if (PTE_PRESENT(pte)) {
1423 jermar 989
            if (((access == PF_ACCESS_READ) && PTE_READABLE(pte)) ||
2087 jermar 990
                (access == PF_ACCESS_WRITE && PTE_WRITABLE(pte)) ||
991
                (access == PF_ACCESS_EXEC && PTE_EXECUTABLE(pte))) {
1423 jermar 992
                page_table_unlock(AS, false);
993
                mutex_unlock(&area->lock);
994
                mutex_unlock(&AS->lock);
995
                return AS_PF_OK;
996
            }
1044 jermar 997
        }
998
    }
1409 jermar 999
 
1044 jermar 1000
    /*
1409 jermar 1001
     * Resort to the backend page fault handler.
703 jermar 1002
     */
1424 jermar 1003
    if (area->backend->page_fault(area, page, access) != AS_PF_OK) {
1409 jermar 1004
        page_table_unlock(AS, false);
1005
        mutex_unlock(&area->lock);
1006
        mutex_unlock(&AS->lock);
1007
        goto page_fault;
1008
    }
703 jermar 1009
 
1044 jermar 1010
    page_table_unlock(AS, false);
1380 jermar 1011
    mutex_unlock(&area->lock);
1012
    mutex_unlock(&AS->lock);
1288 jermar 1013
    return AS_PF_OK;
1014
 
1015
page_fault:
1016
    if (THREAD->in_copy_from_uspace) {
1017
        THREAD->in_copy_from_uspace = false;
2087 jermar 1018
        istate_set_retaddr(istate,
1019
            (uintptr_t) &memcpy_from_uspace_failover_address);
1288 jermar 1020
    } else if (THREAD->in_copy_to_uspace) {
1021
        THREAD->in_copy_to_uspace = false;
2087 jermar 1022
        istate_set_retaddr(istate,
1023
            (uintptr_t) &memcpy_to_uspace_failover_address);
1288 jermar 1024
    } else {
1025
        return AS_PF_FAULT;
1026
    }
1027
 
1028
    return AS_PF_DEFER;
703 jermar 1029
}
1030
 
823 jermar 1031
/** Switch address spaces.
703 jermar 1032
 *
1380 jermar 1033
 * Note that this function cannot sleep as it is essentially a part of
2170 jermar 1034
 * scheduling. Sleeping here would lead to deadlock on wakeup. Another
1035
 * thing which is forbidden in this context is locking the address space.
1380 jermar 1036
 *
2183 jermar 1037
 * When this function is enetered, no spinlocks may be held.
1038
 *
3425 svoboda 1039
 * @param old       Old address space or NULL.
1040
 * @param new       New address space.
703 jermar 1041
 */
2106 jermar 1042
void as_switch(as_t *old_as, as_t *new_as)
703 jermar 1043
{
2183 jermar 1044
    DEADLOCK_PROBE_INIT(p_asidlock);
1045
    preemption_disable();
1046
retry:
1047
    (void) interrupts_disable();
1048
    if (!spinlock_trylock(&asidlock)) {
1049
        /*
1050
         * Avoid deadlock with TLB shootdown.
1051
         * We can enable interrupts here because
1052
         * preemption is disabled. We should not be
1053
         * holding any other lock.
1054
         */
1055
        (void) interrupts_enable();
1056
        DEADLOCK_PROBE(p_asidlock, DEADLOCK_THRESHOLD);
1057
        goto retry;
1058
    }
1059
    preemption_enable();
703 jermar 1060
 
1061
    /*
823 jermar 1062
     * First, take care of the old address space.
1063
     */
2106 jermar 1064
    if (old_as) {
1065
        ASSERT(old_as->cpu_refcount);
1066
        if((--old_as->cpu_refcount == 0) && (old_as != AS_KERNEL)) {
823 jermar 1067
            /*
1068
             * The old address space is no longer active on
1069
             * any processor. It can be appended to the
1070
             * list of inactive address spaces with assigned
1071
             * ASID.
1072
             */
2141 jermar 1073
            ASSERT(old_as->asid != ASID_INVALID);
1074
            list_append(&old_as->inactive_as_with_asid_link,
1075
                &inactive_as_with_asid_head);
823 jermar 1076
        }
1890 jermar 1077
 
1078
        /*
1079
         * Perform architecture-specific tasks when the address space
1080
         * is being removed from the CPU.
1081
         */
2106 jermar 1082
        as_deinstall_arch(old_as);
823 jermar 1083
    }
1084
 
1085
    /*
1086
     * Second, prepare the new address space.
1087
     */
2106 jermar 1088
    if ((new_as->cpu_refcount++ == 0) && (new_as != AS_KERNEL)) {
2170 jermar 1089
        if (new_as->asid != ASID_INVALID)
2106 jermar 1090
            list_remove(&new_as->inactive_as_with_asid_link);
2170 jermar 1091
        else
1092
            new_as->asid = asid_get();
823 jermar 1093
    }
2106 jermar 1094
#ifdef AS_PAGE_TABLE
1095
    SET_PTL0_ADDRESS(new_as->genarch.page_table);
1096
#endif
823 jermar 1097
 
1098
    /*
703 jermar 1099
     * Perform architecture-specific steps.
727 jermar 1100
     * (e.g. write ASID to hardware register etc.)
703 jermar 1101
     */
2106 jermar 1102
    as_install_arch(new_as);
2170 jermar 1103
 
1104
    spinlock_unlock(&asidlock);
703 jermar 1105
 
2106 jermar 1106
    AS = new_as;
703 jermar 1107
}
754 jermar 1108
 
1235 jermar 1109
/** Convert address space area flags to page flags.
754 jermar 1110
 *
3425 svoboda 1111
 * @param aflags    Flags of some address space area.
754 jermar 1112
 *
3425 svoboda 1113
 * @return      Flags to be passed to page_mapping_insert().
754 jermar 1114
 */
1235 jermar 1115
int area_flags_to_page_flags(int aflags)
754 jermar 1116
{
1117
    int flags;
1118
 
1178 jermar 1119
    flags = PAGE_USER | PAGE_PRESENT;
754 jermar 1120
 
1235 jermar 1121
    if (aflags & AS_AREA_READ)
1026 jermar 1122
        flags |= PAGE_READ;
1123
 
1235 jermar 1124
    if (aflags & AS_AREA_WRITE)
1026 jermar 1125
        flags |= PAGE_WRITE;
1126
 
1235 jermar 1127
    if (aflags & AS_AREA_EXEC)
1026 jermar 1128
        flags |= PAGE_EXEC;
1129
 
1424 jermar 1130
    if (aflags & AS_AREA_CACHEABLE)
1178 jermar 1131
        flags |= PAGE_CACHEABLE;
1132
 
754 jermar 1133
    return flags;
1134
}
756 jermar 1135
 
1235 jermar 1136
/** Compute flags for virtual address translation subsytem.
1137
 *
1138
 * The address space area must be locked.
1139
 * Interrupts must be disabled.
1140
 *
3425 svoboda 1141
 * @param a     Address space area.
1235 jermar 1142
 *
3425 svoboda 1143
 * @return      Flags to be used in page_mapping_insert().
1235 jermar 1144
 */
1409 jermar 1145
int as_area_get_flags(as_area_t *a)
1235 jermar 1146
{
1147
    return area_flags_to_page_flags(a->flags);
1148
}
1149
 
756 jermar 1150
/** Create page table.
1151
 *
3425 svoboda 1152
 * Depending on architecture, create either address space private or global page
1153
 * table.
756 jermar 1154
 *
3425 svoboda 1155
 * @param flags     Flags saying whether the page table is for the kernel
1156
 *          address space.
756 jermar 1157
 *
3425 svoboda 1158
 * @return      First entry of the page table.
756 jermar 1159
 */
1160
pte_t *page_table_create(int flags)
1161
{
2125 decky 1162
    ASSERT(as_operations);
1163
    ASSERT(as_operations->page_table_create);
1164
 
1165
    return as_operations->page_table_create(flags);
756 jermar 1166
}
977 jermar 1167
 
1468 jermar 1168
/** Destroy page table.
1169
 *
1170
 * Destroy page table in architecture specific way.
1171
 *
3425 svoboda 1172
 * @param page_table    Physical address of PTL0.
1468 jermar 1173
 */
1174
void page_table_destroy(pte_t *page_table)
1175
{
2125 decky 1176
    ASSERT(as_operations);
1177
    ASSERT(as_operations->page_table_destroy);
1178
 
1179
    as_operations->page_table_destroy(page_table);
1468 jermar 1180
}
1181
 
1044 jermar 1182
/** Lock page table.
1183
 *
1184
 * This function should be called before any page_mapping_insert(),
1185
 * page_mapping_remove() and page_mapping_find().
1186
 *
1187
 * Locking order is such that address space areas must be locked
1188
 * prior to this call. Address space can be locked prior to this
1189
 * call in which case the lock argument is false.
1190
 *
3425 svoboda 1191
 * @param as        Address space.
1192
 * @param lock      If false, do not attempt to lock as->lock.
1044 jermar 1193
 */
1194
void page_table_lock(as_t *as, bool lock)
1195
{
1196
    ASSERT(as_operations);
1197
    ASSERT(as_operations->page_table_lock);
2125 decky 1198
 
1044 jermar 1199
    as_operations->page_table_lock(as, lock);
1200
}
1201
 
1202
/** Unlock page table.
1203
 *
3425 svoboda 1204
 * @param as        Address space.
1205
 * @param unlock    If false, do not attempt to unlock as->lock.
1044 jermar 1206
 */
1207
void page_table_unlock(as_t *as, bool unlock)
1208
{
1209
    ASSERT(as_operations);
1210
    ASSERT(as_operations->page_table_unlock);
2125 decky 1211
 
1044 jermar 1212
    as_operations->page_table_unlock(as, unlock);
1213
}
1214
 
977 jermar 1215
 
1216
/** Find address space area and lock it.
1217
 *
1218
 * The address space must be locked and interrupts must be disabled.
1219
 *
3425 svoboda 1220
 * @param as        Address space.
1221
 * @param va        Virtual address.
977 jermar 1222
 *
3425 svoboda 1223
 * @return      Locked address space area containing va on success or
1224
 *          NULL on failure.
977 jermar 1225
 */
1780 jermar 1226
as_area_t *find_area_and_lock(as_t *as, uintptr_t va)
977 jermar 1227
{
1228
    as_area_t *a;
1147 jermar 1229
    btree_node_t *leaf, *lnode;
2745 decky 1230
    unsigned int i;
977 jermar 1231
 
1147 jermar 1232
    a = (as_area_t *) btree_search(&as->as_area_btree, va, &leaf);
1233
    if (a) {
1234
        /* va is the base address of an address space area */
1380 jermar 1235
        mutex_lock(&a->lock);
1147 jermar 1236
        return a;
1237
    }
1238
 
1239
    /*
1150 jermar 1240
     * Search the leaf node and the righmost record of its left neighbour
1147 jermar 1241
     * to find out whether this is a miss or va belongs to an address
1242
     * space area found there.
1243
     */
1244
 
1245
    /* First, search the leaf node itself. */
1246
    for (i = 0; i < leaf->keys; i++) {
1247
        a = (as_area_t *) leaf->value[i];
1380 jermar 1248
        mutex_lock(&a->lock);
1147 jermar 1249
        if ((a->base <= va) && (va < a->base + a->pages * PAGE_SIZE)) {
1250
            return a;
1251
        }
1380 jermar 1252
        mutex_unlock(&a->lock);
1147 jermar 1253
    }
977 jermar 1254
 
1147 jermar 1255
    /*
1150 jermar 1256
     * Second, locate the left neighbour and test its last record.
1148 jermar 1257
     * Because of its position in the B+tree, it must have base < va.
1147 jermar 1258
     */
2087 jermar 1259
    lnode = btree_leaf_node_left_neighbour(&as->as_area_btree, leaf);
1260
    if (lnode) {
1147 jermar 1261
        a = (as_area_t *) lnode->value[lnode->keys - 1];
1380 jermar 1262
        mutex_lock(&a->lock);
1147 jermar 1263
        if (va < a->base + a->pages * PAGE_SIZE) {
1048 jermar 1264
            return a;
1147 jermar 1265
        }
1380 jermar 1266
        mutex_unlock(&a->lock);
977 jermar 1267
    }
1268
 
1269
    return NULL;
1270
}
1048 jermar 1271
 
1272
/** Check area conflicts with other areas.
1273
 *
1274
 * The address space must be locked and interrupts must be disabled.
1275
 *
3425 svoboda 1276
 * @param as        Address space.
1277
 * @param va        Starting virtual address of the area being tested.
1278
 * @param size      Size of the area being tested.
1279
 * @param avoid_area    Do not touch this area.
1048 jermar 1280
 *
3425 svoboda 1281
 * @return      True if there is no conflict, false otherwise.
1048 jermar 1282
 */
3425 svoboda 1283
bool
1284
check_area_conflicts(as_t *as, uintptr_t va, size_t size, as_area_t *avoid_area)
1048 jermar 1285
{
1286
    as_area_t *a;
1147 jermar 1287
    btree_node_t *leaf, *node;
2745 decky 1288
    unsigned int i;
1048 jermar 1289
 
1070 jermar 1290
    /*
1291
     * We don't want any area to have conflicts with NULL page.
1292
     */
1293
    if (overlaps(va, size, NULL, PAGE_SIZE))
1294
        return false;
1295
 
1147 jermar 1296
    /*
1297
     * The leaf node is found in O(log n), where n is proportional to
1298
     * the number of address space areas belonging to as.
1299
     * The check for conflicts is then attempted on the rightmost
1150 jermar 1300
     * record in the left neighbour, the leftmost record in the right
1301
     * neighbour and all records in the leaf node itself.
1147 jermar 1302
     */
1048 jermar 1303
 
1147 jermar 1304
    if ((a = (as_area_t *) btree_search(&as->as_area_btree, va, &leaf))) {
1305
        if (a != avoid_area)
1306
            return false;
1307
    }
1308
 
1309
    /* First, check the two border cases. */
1150 jermar 1310
    if ((node = btree_leaf_node_left_neighbour(&as->as_area_btree, leaf))) {
1147 jermar 1311
        a = (as_area_t *) node->value[node->keys - 1];
1380 jermar 1312
        mutex_lock(&a->lock);
1147 jermar 1313
        if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
1380 jermar 1314
            mutex_unlock(&a->lock);
1147 jermar 1315
            return false;
1316
        }
1380 jermar 1317
        mutex_unlock(&a->lock);
1147 jermar 1318
    }
2087 jermar 1319
    node = btree_leaf_node_right_neighbour(&as->as_area_btree, leaf);
1320
    if (node) {
1147 jermar 1321
        a = (as_area_t *) node->value[0];
1380 jermar 1322
        mutex_lock(&a->lock);
1147 jermar 1323
        if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
1380 jermar 1324
            mutex_unlock(&a->lock);
1147 jermar 1325
            return false;
1326
        }
1380 jermar 1327
        mutex_unlock(&a->lock);
1147 jermar 1328
    }
1329
 
1330
    /* Second, check the leaf node. */
1331
    for (i = 0; i < leaf->keys; i++) {
1332
        a = (as_area_t *) leaf->value[i];
1333
 
1048 jermar 1334
        if (a == avoid_area)
1335
            continue;
1147 jermar 1336
 
1380 jermar 1337
        mutex_lock(&a->lock);
1147 jermar 1338
        if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
1380 jermar 1339
            mutex_unlock(&a->lock);
1147 jermar 1340
            return false;
1341
        }
1380 jermar 1342
        mutex_unlock(&a->lock);
1048 jermar 1343
    }
1344
 
1070 jermar 1345
    /*
1346
     * So far, the area does not conflict with other areas.
1347
     * Check if it doesn't conflict with kernel address space.
1348
     */  
1349
    if (!KERNEL_ADDRESS_SPACE_SHADOWED) {
1350
        return !overlaps(va, size,
2087 jermar 1351
            KERNEL_ADDRESS_SPACE_START,
1352
            KERNEL_ADDRESS_SPACE_END - KERNEL_ADDRESS_SPACE_START);
1070 jermar 1353
    }
1354
 
1048 jermar 1355
    return true;
1356
}
1235 jermar 1357
 
2556 jermar 1358
/** Return size of the address space area with given base.
1359
 *
1360
 * @param base      Arbitrary address insede the address space area.
1361
 *
1362
 * @return      Size of the address space area in bytes or zero if it
1363
 *          does not exist.
1364
 */
1365
size_t as_area_get_size(uintptr_t base)
1329 palkovsky 1366
{
1367
    ipl_t ipl;
1368
    as_area_t *src_area;
1369
    size_t size;
1370
 
1371
    ipl = interrupts_disable();
1372
    src_area = find_area_and_lock(AS, base);
3425 svoboda 1373
    if (src_area) {
1329 palkovsky 1374
        size = src_area->pages * PAGE_SIZE;
1380 jermar 1375
        mutex_unlock(&src_area->lock);
1329 palkovsky 1376
    } else {
1377
        size = 0;
1378
    }
1379
    interrupts_restore(ipl);
1380
    return size;
1381
}
1382
 
1387 jermar 1383
/** Mark portion of address space area as used.
1384
 *
1385
 * The address space area must be already locked.
1386
 *
3425 svoboda 1387
 * @param a     Address space area.
1388
 * @param page      First page to be marked.
1389
 * @param count     Number of page to be marked.
1387 jermar 1390
 *
3425 svoboda 1391
 * @return      Zero on failure and non-zero on success.
1387 jermar 1392
 */
1780 jermar 1393
int used_space_insert(as_area_t *a, uintptr_t page, count_t count)
1387 jermar 1394
{
1395
    btree_node_t *leaf, *node;
1396
    count_t pages;
2745 decky 1397
    unsigned int i;
1387 jermar 1398
 
1399
    ASSERT(page == ALIGN_DOWN(page, PAGE_SIZE));
1400
    ASSERT(count);
1401
 
1402
    pages = (count_t) btree_search(&a->used_space, page, &leaf);
1403
    if (pages) {
1404
        /*
1405
         * We hit the beginning of some used space.
1406
         */
1407
        return 0;
1408
    }
1409
 
1437 jermar 1410
    if (!leaf->keys) {
1411
        btree_insert(&a->used_space, page, (void *) count, leaf);
1412
        return 1;
1413
    }
1414
 
1387 jermar 1415
    node = btree_leaf_node_left_neighbour(&a->used_space, leaf);
1416
    if (node) {
2087 jermar 1417
        uintptr_t left_pg = node->key[node->keys - 1];
1418
        uintptr_t right_pg = leaf->key[0];
1419
        count_t left_cnt = (count_t) node->value[node->keys - 1];
1420
        count_t right_cnt = (count_t) leaf->value[0];
1387 jermar 1421
 
1422
        /*
1423
         * Examine the possibility that the interval fits
1424
         * somewhere between the rightmost interval of
1425
         * the left neigbour and the first interval of the leaf.
1426
         */
1427
 
1428
        if (page >= right_pg) {
1429
            /* Do nothing. */
2087 jermar 1430
        } else if (overlaps(page, count * PAGE_SIZE, left_pg,
1431
            left_cnt * PAGE_SIZE)) {
1387 jermar 1432
            /* The interval intersects with the left interval. */
1433
            return 0;
2087 jermar 1434
        } else if (overlaps(page, count * PAGE_SIZE, right_pg,
1435
            right_cnt * PAGE_SIZE)) {
1387 jermar 1436
            /* The interval intersects with the right interval. */
1437
            return 0;          
2087 jermar 1438
        } else if ((page == left_pg + left_cnt * PAGE_SIZE) &&
1439
            (page + count * PAGE_SIZE == right_pg)) {
1440
            /*
1441
             * The interval can be added by merging the two already
1442
             * present intervals.
1443
             */
1403 jermar 1444
            node->value[node->keys - 1] += count + right_cnt;
1387 jermar 1445
            btree_remove(&a->used_space, right_pg, leaf);
1446
            return 1;
2087 jermar 1447
        } else if (page == left_pg + left_cnt * PAGE_SIZE) {
1448
            /*
1449
             * The interval can be added by simply growing the left
1450
             * interval.
1451
             */
1403 jermar 1452
            node->value[node->keys - 1] += count;
1387 jermar 1453
            return 1;
2087 jermar 1454
        } else if (page + count * PAGE_SIZE == right_pg) {
1387 jermar 1455
            /*
2087 jermar 1456
             * The interval can be addded by simply moving base of
1457
             * the right interval down and increasing its size
1458
             * accordingly.
1387 jermar 1459
             */
1403 jermar 1460
            leaf->value[0] += count;
1387 jermar 1461
            leaf->key[0] = page;
1462
            return 1;
1463
        } else {
1464
            /*
1465
             * The interval is between both neigbouring intervals,
1466
             * but cannot be merged with any of them.
1467
             */
2087 jermar 1468
            btree_insert(&a->used_space, page, (void *) count,
1469
                leaf);
1387 jermar 1470
            return 1;
1471
        }
1472
    } else if (page < leaf->key[0]) {
1780 jermar 1473
        uintptr_t right_pg = leaf->key[0];
1387 jermar 1474
        count_t right_cnt = (count_t) leaf->value[0];
1475
 
1476
        /*
2087 jermar 1477
         * Investigate the border case in which the left neighbour does
1478
         * not exist but the interval fits from the left.
1387 jermar 1479
         */
1480
 
2087 jermar 1481
        if (overlaps(page, count * PAGE_SIZE, right_pg,
1482
            right_cnt * PAGE_SIZE)) {
1387 jermar 1483
            /* The interval intersects with the right interval. */
1484
            return 0;
2087 jermar 1485
        } else if (page + count * PAGE_SIZE == right_pg) {
1387 jermar 1486
            /*
2087 jermar 1487
             * The interval can be added by moving the base of the
1488
             * right interval down and increasing its size
1489
             * accordingly.
1387 jermar 1490
             */
1491
            leaf->key[0] = page;
1403 jermar 1492
            leaf->value[0] += count;
1387 jermar 1493
            return 1;
1494
        } else {
1495
            /*
1496
             * The interval doesn't adjoin with the right interval.
1497
             * It must be added individually.
1498
             */
2087 jermar 1499
            btree_insert(&a->used_space, page, (void *) count,
1500
                leaf);
1387 jermar 1501
            return 1;
1502
        }
1503
    }
1504
 
1505
    node = btree_leaf_node_right_neighbour(&a->used_space, leaf);
1506
    if (node) {
2087 jermar 1507
        uintptr_t left_pg = leaf->key[leaf->keys - 1];
1508
        uintptr_t right_pg = node->key[0];
1509
        count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
1510
        count_t right_cnt = (count_t) node->value[0];
1387 jermar 1511
 
1512
        /*
1513
         * Examine the possibility that the interval fits
1514
         * somewhere between the leftmost interval of
1515
         * the right neigbour and the last interval of the leaf.
1516
         */
1517
 
1518
        if (page < left_pg) {
1519
            /* Do nothing. */
2087 jermar 1520
        } else if (overlaps(page, count * PAGE_SIZE, left_pg,
1521
            left_cnt * PAGE_SIZE)) {
1387 jermar 1522
            /* The interval intersects with the left interval. */
1523
            return 0;
2087 jermar 1524
        } else if (overlaps(page, count * PAGE_SIZE, right_pg,
1525
            right_cnt * PAGE_SIZE)) {
1387 jermar 1526
            /* The interval intersects with the right interval. */
1527
            return 0;          
2087 jermar 1528
        } else if ((page == left_pg + left_cnt * PAGE_SIZE) &&
1529
            (page + count * PAGE_SIZE == right_pg)) {
1530
            /*
1531
             * The interval can be added by merging the two already
1532
             * present intervals.
1533
             * */
1403 jermar 1534
            leaf->value[leaf->keys - 1] += count + right_cnt;
1387 jermar 1535
            btree_remove(&a->used_space, right_pg, node);
1536
            return 1;
2087 jermar 1537
        } else if (page == left_pg + left_cnt * PAGE_SIZE) {
1538
            /*
1539
             * The interval can be added by simply growing the left
1540
             * interval.
1541
             * */
1403 jermar 1542
            leaf->value[leaf->keys - 1] +=  count;
1387 jermar 1543
            return 1;
2087 jermar 1544
        } else if (page + count * PAGE_SIZE == right_pg) {
1387 jermar 1545
            /*
2087 jermar 1546
             * The interval can be addded by simply moving base of
1547
             * the right interval down and increasing its size
1548
             * accordingly.
1387 jermar 1549
             */
1403 jermar 1550
            node->value[0] += count;
1387 jermar 1551
            node->key[0] = page;
1552
            return 1;
1553
        } else {
1554
            /*
1555
             * The interval is between both neigbouring intervals,
1556
             * but cannot be merged with any of them.
1557
             */
2087 jermar 1558
            btree_insert(&a->used_space, page, (void *) count,
1559
                leaf);
1387 jermar 1560
            return 1;
1561
        }
1562
    } else if (page >= leaf->key[leaf->keys - 1]) {
1780 jermar 1563
        uintptr_t left_pg = leaf->key[leaf->keys - 1];
1387 jermar 1564
        count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
1565
 
1566
        /*
2087 jermar 1567
         * Investigate the border case in which the right neighbour
1568
         * does not exist but the interval fits from the right.
1387 jermar 1569
         */
1570
 
2087 jermar 1571
        if (overlaps(page, count * PAGE_SIZE, left_pg,
1572
            left_cnt * PAGE_SIZE)) {
1403 jermar 1573
            /* The interval intersects with the left interval. */
1387 jermar 1574
            return 0;
2087 jermar 1575
        } else if (left_pg + left_cnt * PAGE_SIZE == page) {
1576
            /*
1577
             * The interval can be added by growing the left
1578
             * interval.
1579
             */
1403 jermar 1580
            leaf->value[leaf->keys - 1] += count;
1387 jermar 1581
            return 1;
1582
        } else {
1583
            /*
1584
             * The interval doesn't adjoin with the left interval.
1585
             * It must be added individually.
1586
             */
2087 jermar 1587
            btree_insert(&a->used_space, page, (void *) count,
1588
                leaf);
1387 jermar 1589
            return 1;
1590
        }
1591
    }
1592
 
1593
    /*
2087 jermar 1594
     * Note that if the algorithm made it thus far, the interval can fit
1595
     * only between two other intervals of the leaf. The two border cases
1596
     * were already resolved.
1387 jermar 1597
     */
1598
    for (i = 1; i < leaf->keys; i++) {
1599
        if (page < leaf->key[i]) {
2087 jermar 1600
            uintptr_t left_pg = leaf->key[i - 1];
1601
            uintptr_t right_pg = leaf->key[i];
1602
            count_t left_cnt = (count_t) leaf->value[i - 1];
1603
            count_t right_cnt = (count_t) leaf->value[i];
1387 jermar 1604
 
1605
            /*
1606
             * The interval fits between left_pg and right_pg.
1607
             */
1608
 
2087 jermar 1609
            if (overlaps(page, count * PAGE_SIZE, left_pg,
1610
                left_cnt * PAGE_SIZE)) {
1611
                /*
1612
                 * The interval intersects with the left
1613
                 * interval.
1614
                 */
1387 jermar 1615
                return 0;
2087 jermar 1616
            } else if (overlaps(page, count * PAGE_SIZE, right_pg,
1617
                right_cnt * PAGE_SIZE)) {
1618
                /*
1619
                 * The interval intersects with the right
1620
                 * interval.
1621
                 */
1387 jermar 1622
                return 0;          
2087 jermar 1623
            } else if ((page == left_pg + left_cnt * PAGE_SIZE) &&
1624
                (page + count * PAGE_SIZE == right_pg)) {
1625
                /*
1626
                 * The interval can be added by merging the two
1627
                 * already present intervals.
1628
                 */
1403 jermar 1629
                leaf->value[i - 1] += count + right_cnt;
1387 jermar 1630
                btree_remove(&a->used_space, right_pg, leaf);
1631
                return 1;
2087 jermar 1632
            } else if (page == left_pg + left_cnt * PAGE_SIZE) {
1633
                /*
1634
                 * The interval can be added by simply growing
1635
                 * the left interval.
1636
                 */
1403 jermar 1637
                leaf->value[i - 1] += count;
1387 jermar 1638
                return 1;
2087 jermar 1639
            } else if (page + count * PAGE_SIZE == right_pg) {
1387 jermar 1640
                /*
2087 jermar 1641
                     * The interval can be addded by simply moving
1642
                 * base of the right interval down and
1643
                 * increasing its size accordingly.
1387 jermar 1644
                 */
1403 jermar 1645
                leaf->value[i] += count;
1387 jermar 1646
                leaf->key[i] = page;
1647
                return 1;
1648
            } else {
1649
                /*
2087 jermar 1650
                 * The interval is between both neigbouring
1651
                 * intervals, but cannot be merged with any of
1652
                 * them.
1387 jermar 1653
                 */
2087 jermar 1654
                btree_insert(&a->used_space, page,
1655
                    (void *) count, leaf);
1387 jermar 1656
                return 1;
1657
            }
1658
        }
1659
    }
1660
 
3425 svoboda 1661
    panic("Inconsistency detected while adding %" PRIc " pages of used "
1662
        "space at %p.\n", count, page);
1387 jermar 1663
}
1664
 
1665
/** Mark portion of address space area as unused.
1666
 *
1667
 * The address space area must be already locked.
1668
 *
3425 svoboda 1669
 * @param a     Address space area.
1670
 * @param page      First page to be marked.
1671
 * @param count     Number of page to be marked.
1387 jermar 1672
 *
3425 svoboda 1673
 * @return      Zero on failure and non-zero on success.
1387 jermar 1674
 */
1780 jermar 1675
int used_space_remove(as_area_t *a, uintptr_t page, count_t count)
1387 jermar 1676
{
1677
    btree_node_t *leaf, *node;
1678
    count_t pages;
2745 decky 1679
    unsigned int i;
1387 jermar 1680
 
1681
    ASSERT(page == ALIGN_DOWN(page, PAGE_SIZE));
1682
    ASSERT(count);
1683
 
1684
    pages = (count_t) btree_search(&a->used_space, page, &leaf);
1685
    if (pages) {
1686
        /*
1687
         * We are lucky, page is the beginning of some interval.
1688
         */
1689
        if (count > pages) {
1690
            return 0;
1691
        } else if (count == pages) {
1692
            btree_remove(&a->used_space, page, leaf);
1403 jermar 1693
            return 1;
1387 jermar 1694
        } else {
1695
            /*
1696
             * Find the respective interval.
1697
             * Decrease its size and relocate its start address.
1698
             */
1699
            for (i = 0; i < leaf->keys; i++) {
1700
                if (leaf->key[i] == page) {
2087 jermar 1701
                    leaf->key[i] += count * PAGE_SIZE;
1403 jermar 1702
                    leaf->value[i] -= count;
1387 jermar 1703
                    return 1;
1704
                }
1705
            }
1706
            goto error;
1707
        }
1708
    }
1709
 
1710
    node = btree_leaf_node_left_neighbour(&a->used_space, leaf);
1711
    if (node && page < leaf->key[0]) {
1780 jermar 1712
        uintptr_t left_pg = node->key[node->keys - 1];
1387 jermar 1713
        count_t left_cnt = (count_t) node->value[node->keys - 1];
1714
 
2087 jermar 1715
        if (overlaps(left_pg, left_cnt * PAGE_SIZE, page,
1716
            count * PAGE_SIZE)) {
1717
            if (page + count * PAGE_SIZE ==
1718
                left_pg + left_cnt * PAGE_SIZE) {
1387 jermar 1719
                /*
2087 jermar 1720
                 * The interval is contained in the rightmost
1721
                 * interval of the left neighbour and can be
1722
                 * removed by updating the size of the bigger
1723
                 * interval.
1387 jermar 1724
                 */
1403 jermar 1725
                node->value[node->keys - 1] -= count;
1387 jermar 1726
                return 1;
2087 jermar 1727
            } else if (page + count * PAGE_SIZE <
1728
                left_pg + left_cnt*PAGE_SIZE) {
1403 jermar 1729
                count_t new_cnt;
1387 jermar 1730
 
1731
                /*
2087 jermar 1732
                 * The interval is contained in the rightmost
1733
                 * interval of the left neighbour but its
1734
                 * removal requires both updating the size of
1735
                 * the original interval and also inserting a
1736
                 * new interval.
1387 jermar 1737
                 */
2087 jermar 1738
                new_cnt = ((left_pg + left_cnt * PAGE_SIZE) -
1739
                    (page + count*PAGE_SIZE)) >> PAGE_WIDTH;
1403 jermar 1740
                node->value[node->keys - 1] -= count + new_cnt;
2087 jermar 1741
                btree_insert(&a->used_space, page +
1742
                    count * PAGE_SIZE, (void *) new_cnt, leaf);
1387 jermar 1743
                return 1;
1744
            }
1745
        }
1746
        return 0;
1747
    } else if (page < leaf->key[0]) {
1748
        return 0;
1749
    }
1750
 
1751
    if (page > leaf->key[leaf->keys - 1]) {
1780 jermar 1752
        uintptr_t left_pg = leaf->key[leaf->keys - 1];
1387 jermar 1753
        count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
1754
 
2087 jermar 1755
        if (overlaps(left_pg, left_cnt * PAGE_SIZE, page,
1756
            count * PAGE_SIZE)) {
1757
            if (page + count * PAGE_SIZE ==
1758
                left_pg + left_cnt * PAGE_SIZE) {
1387 jermar 1759
                /*
2087 jermar 1760
                 * The interval is contained in the rightmost
1761
                 * interval of the leaf and can be removed by
1762
                 * updating the size of the bigger interval.
1387 jermar 1763
                 */
1403 jermar 1764
                leaf->value[leaf->keys - 1] -= count;
1387 jermar 1765
                return 1;
2087 jermar 1766
            } else if (page + count * PAGE_SIZE < left_pg +
1767
                left_cnt * PAGE_SIZE) {
1403 jermar 1768
                count_t new_cnt;
1387 jermar 1769
 
1770
                /*
2087 jermar 1771
                 * The interval is contained in the rightmost
1772
                 * interval of the leaf but its removal
1773
                 * requires both updating the size of the
1774
                 * original interval and also inserting a new
1775
                 * interval.
1387 jermar 1776
                 */
2087 jermar 1777
                new_cnt = ((left_pg + left_cnt * PAGE_SIZE) -
1778
                    (page + count * PAGE_SIZE)) >> PAGE_WIDTH;
1403 jermar 1779
                leaf->value[leaf->keys - 1] -= count + new_cnt;
2087 jermar 1780
                btree_insert(&a->used_space, page +
1781
                    count * PAGE_SIZE, (void *) new_cnt, leaf);
1387 jermar 1782
                return 1;
1783
            }
1784
        }
1785
        return 0;
1786
    }  
1787
 
1788
    /*
1789
     * The border cases have been already resolved.
1790
     * Now the interval can be only between intervals of the leaf.
1791
     */
1792
    for (i = 1; i < leaf->keys - 1; i++) {
1793
        if (page < leaf->key[i]) {
1780 jermar 1794
            uintptr_t left_pg = leaf->key[i - 1];
1387 jermar 1795
            count_t left_cnt = (count_t) leaf->value[i - 1];
1796
 
1797
            /*
2087 jermar 1798
             * Now the interval is between intervals corresponding
1799
             * to (i - 1) and i.
1387 jermar 1800
             */
2087 jermar 1801
            if (overlaps(left_pg, left_cnt * PAGE_SIZE, page,
1802
                count * PAGE_SIZE)) {
1803
                if (page + count * PAGE_SIZE ==
1804
                    left_pg + left_cnt*PAGE_SIZE) {
1387 jermar 1805
                    /*
2087 jermar 1806
                     * The interval is contained in the
1807
                     * interval (i - 1) of the leaf and can
1808
                     * be removed by updating the size of
1809
                     * the bigger interval.
1387 jermar 1810
                     */
1403 jermar 1811
                    leaf->value[i - 1] -= count;
1387 jermar 1812
                    return 1;
2087 jermar 1813
                } else if (page + count * PAGE_SIZE <
1814
                    left_pg + left_cnt * PAGE_SIZE) {
1403 jermar 1815
                    count_t new_cnt;
1387 jermar 1816
 
1817
                    /*
2087 jermar 1818
                     * The interval is contained in the
1819
                     * interval (i - 1) of the leaf but its
1820
                     * removal requires both updating the
1821
                     * size of the original interval and
1387 jermar 1822
                     * also inserting a new interval.
1823
                     */
2087 jermar 1824
                    new_cnt = ((left_pg +
1825
                        left_cnt * PAGE_SIZE) -
1826
                        (page + count * PAGE_SIZE)) >>
1827
                        PAGE_WIDTH;
1403 jermar 1828
                    leaf->value[i - 1] -= count + new_cnt;
2087 jermar 1829
                    btree_insert(&a->used_space, page +
1830
                        count * PAGE_SIZE, (void *) new_cnt,
1831
                        leaf);
1387 jermar 1832
                    return 1;
1833
                }
1834
            }
1835
            return 0;
1836
        }
1837
    }
1838
 
1839
error:
3425 svoboda 1840
    panic("Inconsistency detected while removing %" PRIc " pages of used "
1841
        "space from %p.\n", count, page);
1387 jermar 1842
}
1843
 
1409 jermar 1844
/** Remove reference to address space area share info.
1845
 *
1846
 * If the reference count drops to 0, the sh_info is deallocated.
1847
 *
3425 svoboda 1848
 * @param sh_info   Pointer to address space area share info.
1409 jermar 1849
 */
1850
void sh_info_remove_reference(share_info_t *sh_info)
1851
{
1852
    bool dealloc = false;
1853
 
1854
    mutex_lock(&sh_info->lock);
1855
    ASSERT(sh_info->refcount);
1856
    if (--sh_info->refcount == 0) {
1857
        dealloc = true;
1495 jermar 1858
        link_t *cur;
1409 jermar 1859
 
1860
        /*
1861
         * Now walk carefully the pagemap B+tree and free/remove
1862
         * reference from all frames found there.
1863
         */
2087 jermar 1864
        for (cur = sh_info->pagemap.leaf_head.next;
1865
            cur != &sh_info->pagemap.leaf_head; cur = cur->next) {
1409 jermar 1866
            btree_node_t *node;
2745 decky 1867
            unsigned int i;
1409 jermar 1868
 
1495 jermar 1869
            node = list_get_instance(cur, btree_node_t, leaf_link);
1870
            for (i = 0; i < node->keys; i++)
1780 jermar 1871
                frame_free((uintptr_t) node->value[i]);
1409 jermar 1872
        }
1873
 
1874
    }
1875
    mutex_unlock(&sh_info->lock);
1876
 
1877
    if (dealloc) {
1878
        btree_destroy(&sh_info->pagemap);
1879
        free(sh_info);
1880
    }
1881
}
1882
 
1235 jermar 1883
/*
1884
 * Address space related syscalls.
1885
 */
1886
 
1887
/** Wrapper for as_area_create(). */
1780 jermar 1888
unative_t sys_as_area_create(uintptr_t address, size_t size, int flags)
1235 jermar 1889
{
2087 jermar 1890
    if (as_area_create(AS, flags | AS_AREA_CACHEABLE, size, address,
1891
        AS_AREA_ATTR_NONE, &anon_backend, NULL))
1780 jermar 1892
        return (unative_t) address;
1235 jermar 1893
    else
1780 jermar 1894
        return (unative_t) -1;
1235 jermar 1895
}
1896
 
1793 jermar 1897
/** Wrapper for as_area_resize(). */
1780 jermar 1898
unative_t sys_as_area_resize(uintptr_t address, size_t size, int flags)
1235 jermar 1899
{
1780 jermar 1900
    return (unative_t) as_area_resize(AS, address, size, 0);
1235 jermar 1901
}
1902
 
3425 svoboda 1903
/** Wrapper for as_area_change_flags(). */
1904
unative_t sys_as_area_change_flags(uintptr_t address, int flags)
1905
{
1906
    return (unative_t) as_area_change_flags(AS, flags, address);
1907
}
1908
 
1793 jermar 1909
/** Wrapper for as_area_destroy(). */
1780 jermar 1910
unative_t sys_as_area_destroy(uintptr_t address)
1306 jermar 1911
{
1780 jermar 1912
    return (unative_t) as_area_destroy(AS, address);
1306 jermar 1913
}
1702 cejka 1914
 
1914 jermar 1915
/** Print out information about address space.
1916
 *
3425 svoboda 1917
 * @param as        Address space.
1914 jermar 1918
 */
1919
void as_print(as_t *as)
1920
{
1921
    ipl_t ipl;
1922
 
1923
    ipl = interrupts_disable();
1924
    mutex_lock(&as->lock);
1925
 
1926
    /* print out info about address space areas */
1927
    link_t *cur;
2087 jermar 1928
    for (cur = as->as_area_btree.leaf_head.next;
1929
        cur != &as->as_area_btree.leaf_head; cur = cur->next) {
1930
        btree_node_t *node;
1914 jermar 1931
 
2087 jermar 1932
        node = list_get_instance(cur, btree_node_t, leaf_link);
1933
 
2745 decky 1934
        unsigned int i;
1914 jermar 1935
        for (i = 0; i < node->keys; i++) {
1915 jermar 1936
            as_area_t *area = node->value[i];
1914 jermar 1937
 
1938
            mutex_lock(&area->lock);
3425 svoboda 1939
            printf("as_area: %p, base=%p, pages=%" PRIc
1940
                " (%p - %p)\n", area, area->base, area->pages,
1941
                area->base, area->base + FRAMES2SIZE(area->pages));
1914 jermar 1942
            mutex_unlock(&area->lock);
1943
        }
1944
    }
1945
 
1946
    mutex_unlock(&as->lock);
1947
    interrupts_restore(ipl);
1948
}
1949
 
1757 jermar 1950
/** @}
1702 cejka 1951
 */