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1 | /** @file |
2 | UEFI Heap Guard functions. | |
3 | ||
4 | Copyright (c) 2017, Intel Corporation. All rights reserved.<BR> | |
5 | This program and the accompanying materials | |
6 | are licensed and made available under the terms and conditions of the BSD License | |
7 | which accompanies this distribution. The full text of the license may be found at | |
8 | http://opensource.org/licenses/bsd-license.php | |
9 | ||
10 | THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, | |
11 | WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. | |
12 | ||
13 | **/ | |
14 | ||
15 | #include "DxeMain.h" | |
16 | #include "Imem.h" | |
17 | #include "HeapGuard.h" | |
18 | ||
19 | // | |
20 | // Global to avoid infinite reentrance of memory allocation when updating | |
21 | // page table attributes, which may need allocate pages for new PDE/PTE. | |
22 | // | |
23 | GLOBAL_REMOVE_IF_UNREFERENCED BOOLEAN mOnGuarding = FALSE; | |
24 | ||
25 | // | |
26 | // Pointer to table tracking the Guarded memory with bitmap, in which '1' | |
27 | // is used to indicate memory guarded. '0' might be free memory or Guard | |
28 | // page itself, depending on status of memory adjacent to it. | |
29 | // | |
30 | GLOBAL_REMOVE_IF_UNREFERENCED UINT64 mGuardedMemoryMap = 0; | |
31 | ||
32 | // | |
33 | // Current depth level of map table pointed by mGuardedMemoryMap. | |
34 | // mMapLevel must be initialized at least by 1. It will be automatically | |
35 | // updated according to the address of memory just tracked. | |
36 | // | |
37 | GLOBAL_REMOVE_IF_UNREFERENCED UINTN mMapLevel = 1; | |
38 | ||
39 | // | |
40 | // Shift and mask for each level of map table | |
41 | // | |
42 | GLOBAL_REMOVE_IF_UNREFERENCED UINTN mLevelShift[GUARDED_HEAP_MAP_TABLE_DEPTH] | |
43 | = GUARDED_HEAP_MAP_TABLE_DEPTH_SHIFTS; | |
44 | GLOBAL_REMOVE_IF_UNREFERENCED UINTN mLevelMask[GUARDED_HEAP_MAP_TABLE_DEPTH] | |
45 | = GUARDED_HEAP_MAP_TABLE_DEPTH_MASKS; | |
46 | ||
47 | /** | |
48 | Set corresponding bits in bitmap table to 1 according to the address. | |
49 | ||
50 | @param[in] Address Start address to set for. | |
51 | @param[in] BitNumber Number of bits to set. | |
52 | @param[in] BitMap Pointer to bitmap which covers the Address. | |
53 | ||
54 | @return VOID. | |
55 | **/ | |
56 | STATIC | |
57 | VOID | |
58 | SetBits ( | |
59 | IN EFI_PHYSICAL_ADDRESS Address, | |
60 | IN UINTN BitNumber, | |
61 | IN UINT64 *BitMap | |
62 | ) | |
63 | { | |
64 | UINTN Lsbs; | |
65 | UINTN Qwords; | |
66 | UINTN Msbs; | |
67 | UINTN StartBit; | |
68 | UINTN EndBit; | |
69 | ||
70 | StartBit = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address); | |
71 | EndBit = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS; | |
72 | ||
73 | if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) { | |
74 | Msbs = (GUARDED_HEAP_MAP_ENTRY_BITS - StartBit) % | |
75 | GUARDED_HEAP_MAP_ENTRY_BITS; | |
76 | Lsbs = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS; | |
77 | Qwords = (BitNumber - Msbs) / GUARDED_HEAP_MAP_ENTRY_BITS; | |
78 | } else { | |
79 | Msbs = BitNumber; | |
80 | Lsbs = 0; | |
81 | Qwords = 0; | |
82 | } | |
83 | ||
84 | if (Msbs > 0) { | |
85 | *BitMap |= LShiftU64 (LShiftU64 (1, Msbs) - 1, StartBit); | |
86 | BitMap += 1; | |
87 | } | |
88 | ||
89 | if (Qwords > 0) { | |
90 | SetMem64 ((VOID *)BitMap, Qwords * GUARDED_HEAP_MAP_ENTRY_BYTES, | |
91 | (UINT64)-1); | |
92 | BitMap += Qwords; | |
93 | } | |
94 | ||
95 | if (Lsbs > 0) { | |
96 | *BitMap |= (LShiftU64 (1, Lsbs) - 1); | |
97 | } | |
98 | } | |
99 | ||
100 | /** | |
101 | Set corresponding bits in bitmap table to 0 according to the address. | |
102 | ||
103 | @param[in] Address Start address to set for. | |
104 | @param[in] BitNumber Number of bits to set. | |
105 | @param[in] BitMap Pointer to bitmap which covers the Address. | |
106 | ||
107 | @return VOID. | |
108 | **/ | |
109 | STATIC | |
110 | VOID | |
111 | ClearBits ( | |
112 | IN EFI_PHYSICAL_ADDRESS Address, | |
113 | IN UINTN BitNumber, | |
114 | IN UINT64 *BitMap | |
115 | ) | |
116 | { | |
117 | UINTN Lsbs; | |
118 | UINTN Qwords; | |
119 | UINTN Msbs; | |
120 | UINTN StartBit; | |
121 | UINTN EndBit; | |
122 | ||
123 | StartBit = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address); | |
124 | EndBit = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS; | |
125 | ||
126 | if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) { | |
127 | Msbs = (GUARDED_HEAP_MAP_ENTRY_BITS - StartBit) % | |
128 | GUARDED_HEAP_MAP_ENTRY_BITS; | |
129 | Lsbs = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS; | |
130 | Qwords = (BitNumber - Msbs) / GUARDED_HEAP_MAP_ENTRY_BITS; | |
131 | } else { | |
132 | Msbs = BitNumber; | |
133 | Lsbs = 0; | |
134 | Qwords = 0; | |
135 | } | |
136 | ||
137 | if (Msbs > 0) { | |
138 | *BitMap &= ~LShiftU64 (LShiftU64 (1, Msbs) - 1, StartBit); | |
139 | BitMap += 1; | |
140 | } | |
141 | ||
142 | if (Qwords > 0) { | |
143 | SetMem64 ((VOID *)BitMap, Qwords * GUARDED_HEAP_MAP_ENTRY_BYTES, 0); | |
144 | BitMap += Qwords; | |
145 | } | |
146 | ||
147 | if (Lsbs > 0) { | |
148 | *BitMap &= ~(LShiftU64 (1, Lsbs) - 1); | |
149 | } | |
150 | } | |
151 | ||
152 | /** | |
153 | Get corresponding bits in bitmap table according to the address. | |
154 | ||
155 | The value of bit 0 corresponds to the status of memory at given Address. | |
156 | No more than 64 bits can be retrieved in one call. | |
157 | ||
158 | @param[in] Address Start address to retrieve bits for. | |
159 | @param[in] BitNumber Number of bits to get. | |
160 | @param[in] BitMap Pointer to bitmap which covers the Address. | |
161 | ||
162 | @return An integer containing the bits information. | |
163 | **/ | |
164 | STATIC | |
165 | UINT64 | |
166 | GetBits ( | |
167 | IN EFI_PHYSICAL_ADDRESS Address, | |
168 | IN UINTN BitNumber, | |
169 | IN UINT64 *BitMap | |
170 | ) | |
171 | { | |
172 | UINTN StartBit; | |
173 | UINTN EndBit; | |
174 | UINTN Lsbs; | |
175 | UINTN Msbs; | |
176 | UINT64 Result; | |
177 | ||
178 | ASSERT (BitNumber <= GUARDED_HEAP_MAP_ENTRY_BITS); | |
179 | ||
180 | StartBit = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address); | |
181 | EndBit = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS; | |
182 | ||
183 | if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) { | |
184 | Msbs = GUARDED_HEAP_MAP_ENTRY_BITS - StartBit; | |
185 | Lsbs = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS; | |
186 | } else { | |
187 | Msbs = BitNumber; | |
188 | Lsbs = 0; | |
189 | } | |
190 | ||
191 | Result = RShiftU64 ((*BitMap), StartBit) & (LShiftU64 (1, Msbs) - 1); | |
192 | if (Lsbs > 0) { | |
193 | BitMap += 1; | |
194 | Result |= LShiftU64 ((*BitMap) & (LShiftU64 (1, Lsbs) - 1), Msbs); | |
195 | } | |
196 | ||
197 | return Result; | |
198 | } | |
199 | ||
200 | /** | |
201 | Locate the pointer of bitmap from the guarded memory bitmap tables, which | |
202 | covers the given Address. | |
203 | ||
204 | @param[in] Address Start address to search the bitmap for. | |
205 | @param[in] AllocMapUnit Flag to indicate memory allocation for the table. | |
206 | @param[out] BitMap Pointer to bitmap which covers the Address. | |
207 | ||
208 | @return The bit number from given Address to the end of current map table. | |
209 | **/ | |
210 | UINTN | |
211 | FindGuardedMemoryMap ( | |
212 | IN EFI_PHYSICAL_ADDRESS Address, | |
213 | IN BOOLEAN AllocMapUnit, | |
214 | OUT UINT64 **BitMap | |
215 | ) | |
216 | { | |
217 | UINTN Level; | |
218 | UINT64 *GuardMap; | |
219 | UINT64 MapMemory; | |
220 | UINTN Index; | |
221 | UINTN Size; | |
222 | UINTN BitsToUnitEnd; | |
223 | EFI_STATUS Status; | |
224 | ||
225 | // | |
226 | // Adjust current map table depth according to the address to access | |
227 | // | |
228 | while (mMapLevel < GUARDED_HEAP_MAP_TABLE_DEPTH | |
229 | && | |
230 | RShiftU64 ( | |
231 | Address, | |
232 | mLevelShift[GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel - 1] | |
233 | ) != 0) { | |
234 | ||
235 | if (mGuardedMemoryMap != 0) { | |
236 | Size = (mLevelMask[GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel - 1] + 1) | |
237 | * GUARDED_HEAP_MAP_ENTRY_BYTES; | |
238 | Status = CoreInternalAllocatePages ( | |
239 | AllocateAnyPages, | |
240 | EfiBootServicesData, | |
241 | EFI_SIZE_TO_PAGES (Size), | |
242 | &MapMemory, | |
243 | FALSE | |
244 | ); | |
245 | ASSERT_EFI_ERROR (Status); | |
246 | ASSERT (MapMemory != 0); | |
247 | ||
248 | SetMem ((VOID *)(UINTN)MapMemory, Size, 0); | |
249 | ||
250 | *(UINT64 *)(UINTN)MapMemory = mGuardedMemoryMap; | |
251 | mGuardedMemoryMap = MapMemory; | |
252 | } | |
253 | ||
254 | mMapLevel++; | |
255 | ||
256 | } | |
257 | ||
258 | GuardMap = &mGuardedMemoryMap; | |
259 | for (Level = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel; | |
260 | Level < GUARDED_HEAP_MAP_TABLE_DEPTH; | |
261 | ++Level) { | |
262 | ||
263 | if (*GuardMap == 0) { | |
264 | if (!AllocMapUnit) { | |
265 | GuardMap = NULL; | |
266 | break; | |
267 | } | |
268 | ||
269 | Size = (mLevelMask[Level] + 1) * GUARDED_HEAP_MAP_ENTRY_BYTES; | |
270 | Status = CoreInternalAllocatePages ( | |
271 | AllocateAnyPages, | |
272 | EfiBootServicesData, | |
273 | EFI_SIZE_TO_PAGES (Size), | |
274 | &MapMemory, | |
275 | FALSE | |
276 | ); | |
277 | ASSERT_EFI_ERROR (Status); | |
278 | ASSERT (MapMemory != 0); | |
279 | ||
280 | SetMem ((VOID *)(UINTN)MapMemory, Size, 0); | |
281 | *GuardMap = MapMemory; | |
282 | } | |
283 | ||
284 | Index = (UINTN)RShiftU64 (Address, mLevelShift[Level]); | |
285 | Index &= mLevelMask[Level]; | |
286 | GuardMap = (UINT64 *)(UINTN)((*GuardMap) + Index * sizeof (UINT64)); | |
287 | ||
288 | } | |
289 | ||
290 | BitsToUnitEnd = GUARDED_HEAP_MAP_BITS - GUARDED_HEAP_MAP_BIT_INDEX (Address); | |
291 | *BitMap = GuardMap; | |
292 | ||
293 | return BitsToUnitEnd; | |
294 | } | |
295 | ||
296 | /** | |
297 | Set corresponding bits in bitmap table to 1 according to given memory range. | |
298 | ||
299 | @param[in] Address Memory address to guard from. | |
300 | @param[in] NumberOfPages Number of pages to guard. | |
301 | ||
302 | @return VOID. | |
303 | **/ | |
304 | VOID | |
305 | EFIAPI | |
306 | SetGuardedMemoryBits ( | |
307 | IN EFI_PHYSICAL_ADDRESS Address, | |
308 | IN UINTN NumberOfPages | |
309 | ) | |
310 | { | |
311 | UINT64 *BitMap; | |
312 | UINTN Bits; | |
313 | UINTN BitsToUnitEnd; | |
314 | ||
315 | while (NumberOfPages > 0) { | |
316 | BitsToUnitEnd = FindGuardedMemoryMap (Address, TRUE, &BitMap); | |
317 | ASSERT (BitMap != NULL); | |
318 | ||
319 | if (NumberOfPages > BitsToUnitEnd) { | |
320 | // Cross map unit | |
321 | Bits = BitsToUnitEnd; | |
322 | } else { | |
323 | Bits = NumberOfPages; | |
324 | } | |
325 | ||
326 | SetBits (Address, Bits, BitMap); | |
327 | ||
328 | NumberOfPages -= Bits; | |
329 | Address += EFI_PAGES_TO_SIZE (Bits); | |
330 | } | |
331 | } | |
332 | ||
333 | /** | |
334 | Clear corresponding bits in bitmap table according to given memory range. | |
335 | ||
336 | @param[in] Address Memory address to unset from. | |
337 | @param[in] NumberOfPages Number of pages to unset guard. | |
338 | ||
339 | @return VOID. | |
340 | **/ | |
341 | VOID | |
342 | EFIAPI | |
343 | ClearGuardedMemoryBits ( | |
344 | IN EFI_PHYSICAL_ADDRESS Address, | |
345 | IN UINTN NumberOfPages | |
346 | ) | |
347 | { | |
348 | UINT64 *BitMap; | |
349 | UINTN Bits; | |
350 | UINTN BitsToUnitEnd; | |
351 | ||
352 | while (NumberOfPages > 0) { | |
353 | BitsToUnitEnd = FindGuardedMemoryMap (Address, TRUE, &BitMap); | |
354 | ASSERT (BitMap != NULL); | |
355 | ||
356 | if (NumberOfPages > BitsToUnitEnd) { | |
357 | // Cross map unit | |
358 | Bits = BitsToUnitEnd; | |
359 | } else { | |
360 | Bits = NumberOfPages; | |
361 | } | |
362 | ||
363 | ClearBits (Address, Bits, BitMap); | |
364 | ||
365 | NumberOfPages -= Bits; | |
366 | Address += EFI_PAGES_TO_SIZE (Bits); | |
367 | } | |
368 | } | |
369 | ||
370 | /** | |
371 | Retrieve corresponding bits in bitmap table according to given memory range. | |
372 | ||
373 | @param[in] Address Memory address to retrieve from. | |
374 | @param[in] NumberOfPages Number of pages to retrieve. | |
375 | ||
376 | @return VOID. | |
377 | **/ | |
378 | UINTN | |
379 | GetGuardedMemoryBits ( | |
380 | IN EFI_PHYSICAL_ADDRESS Address, | |
381 | IN UINTN NumberOfPages | |
382 | ) | |
383 | { | |
384 | UINT64 *BitMap; | |
385 | UINTN Bits; | |
386 | UINTN Result; | |
387 | UINTN Shift; | |
388 | UINTN BitsToUnitEnd; | |
389 | ||
390 | ASSERT (NumberOfPages <= GUARDED_HEAP_MAP_ENTRY_BITS); | |
391 | ||
392 | Result = 0; | |
393 | Shift = 0; | |
394 | while (NumberOfPages > 0) { | |
395 | BitsToUnitEnd = FindGuardedMemoryMap (Address, FALSE, &BitMap); | |
396 | ||
397 | if (NumberOfPages > BitsToUnitEnd) { | |
398 | // Cross map unit | |
399 | Bits = BitsToUnitEnd; | |
400 | } else { | |
401 | Bits = NumberOfPages; | |
402 | } | |
403 | ||
404 | if (BitMap != NULL) { | |
405 | Result |= LShiftU64 (GetBits (Address, Bits, BitMap), Shift); | |
406 | } | |
407 | ||
408 | Shift += Bits; | |
409 | NumberOfPages -= Bits; | |
410 | Address += EFI_PAGES_TO_SIZE (Bits); | |
411 | } | |
412 | ||
413 | return Result; | |
414 | } | |
415 | ||
416 | /** | |
417 | Get bit value in bitmap table for the given address. | |
418 | ||
419 | @param[in] Address The address to retrieve for. | |
420 | ||
421 | @return 1 or 0. | |
422 | **/ | |
423 | UINTN | |
424 | EFIAPI | |
425 | GetGuardMapBit ( | |
426 | IN EFI_PHYSICAL_ADDRESS Address | |
427 | ) | |
428 | { | |
429 | UINT64 *GuardMap; | |
430 | ||
431 | FindGuardedMemoryMap (Address, FALSE, &GuardMap); | |
432 | if (GuardMap != NULL) { | |
433 | if (RShiftU64 (*GuardMap, | |
434 | GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address)) & 1) { | |
435 | return 1; | |
436 | } | |
437 | } | |
438 | ||
439 | return 0; | |
440 | } | |
441 | ||
442 | /** | |
443 | Set the bit in bitmap table for the given address. | |
444 | ||
445 | @param[in] Address The address to set for. | |
446 | ||
447 | @return VOID. | |
448 | **/ | |
449 | VOID | |
450 | EFIAPI | |
451 | SetGuardMapBit ( | |
452 | IN EFI_PHYSICAL_ADDRESS Address | |
453 | ) | |
454 | { | |
455 | UINT64 *GuardMap; | |
456 | UINT64 BitMask; | |
457 | ||
458 | FindGuardedMemoryMap (Address, TRUE, &GuardMap); | |
459 | if (GuardMap != NULL) { | |
460 | BitMask = LShiftU64 (1, GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address)); | |
461 | *GuardMap |= BitMask; | |
462 | } | |
463 | } | |
464 | ||
465 | /** | |
466 | Clear the bit in bitmap table for the given address. | |
467 | ||
468 | @param[in] Address The address to clear for. | |
469 | ||
470 | @return VOID. | |
471 | **/ | |
472 | VOID | |
473 | EFIAPI | |
474 | ClearGuardMapBit ( | |
475 | IN EFI_PHYSICAL_ADDRESS Address | |
476 | ) | |
477 | { | |
478 | UINT64 *GuardMap; | |
479 | UINT64 BitMask; | |
480 | ||
481 | FindGuardedMemoryMap (Address, TRUE, &GuardMap); | |
482 | if (GuardMap != NULL) { | |
483 | BitMask = LShiftU64 (1, GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address)); | |
484 | *GuardMap &= ~BitMask; | |
485 | } | |
486 | } | |
487 | ||
488 | /** | |
489 | Check to see if the page at the given address is a Guard page or not. | |
490 | ||
491 | @param[in] Address The address to check for. | |
492 | ||
493 | @return TRUE The page at Address is a Guard page. | |
494 | @return FALSE The page at Address is not a Guard page. | |
495 | **/ | |
496 | BOOLEAN | |
497 | EFIAPI | |
498 | IsGuardPage ( | |
499 | IN EFI_PHYSICAL_ADDRESS Address | |
500 | ) | |
501 | { | |
502 | UINTN BitMap; | |
503 | ||
504 | BitMap = GetGuardedMemoryBits (Address - EFI_PAGE_SIZE, 3); | |
505 | return ((BitMap == 0b001) || (BitMap == 0b100) || (BitMap == 0b101)); | |
506 | } | |
507 | ||
508 | /** | |
509 | Check to see if the page at the given address is a head Guard page or not. | |
510 | ||
511 | @param[in] Address The address to check for | |
512 | ||
513 | @return TRUE The page at Address is a head Guard page | |
514 | @return FALSE The page at Address is not a head Guard page | |
515 | **/ | |
516 | BOOLEAN | |
517 | EFIAPI | |
518 | IsHeadGuard ( | |
519 | IN EFI_PHYSICAL_ADDRESS Address | |
520 | ) | |
521 | { | |
522 | return (GetGuardedMemoryBits (Address, 2) == 0b10); | |
523 | } | |
524 | ||
525 | /** | |
526 | Check to see if the page at the given address is a tail Guard page or not. | |
527 | ||
528 | @param[in] Address The address to check for. | |
529 | ||
530 | @return TRUE The page at Address is a tail Guard page. | |
531 | @return FALSE The page at Address is not a tail Guard page. | |
532 | **/ | |
533 | BOOLEAN | |
534 | EFIAPI | |
535 | IsTailGuard ( | |
536 | IN EFI_PHYSICAL_ADDRESS Address | |
537 | ) | |
538 | { | |
539 | return (GetGuardedMemoryBits (Address - EFI_PAGE_SIZE, 2) == 0b01); | |
540 | } | |
541 | ||
542 | /** | |
543 | Check to see if the page at the given address is guarded or not. | |
544 | ||
545 | @param[in] Address The address to check for. | |
546 | ||
547 | @return TRUE The page at Address is guarded. | |
548 | @return FALSE The page at Address is not guarded. | |
549 | **/ | |
550 | BOOLEAN | |
551 | EFIAPI | |
552 | IsMemoryGuarded ( | |
553 | IN EFI_PHYSICAL_ADDRESS Address | |
554 | ) | |
555 | { | |
556 | return (GetGuardMapBit (Address) == 1); | |
557 | } | |
558 | ||
559 | /** | |
560 | Set the page at the given address to be a Guard page. | |
561 | ||
562 | This is done by changing the page table attribute to be NOT PRSENT. | |
563 | ||
564 | @param[in] BaseAddress Page address to Guard at | |
565 | ||
566 | @return VOID | |
567 | **/ | |
568 | VOID | |
569 | EFIAPI | |
570 | SetGuardPage ( | |
571 | IN EFI_PHYSICAL_ADDRESS BaseAddress | |
572 | ) | |
573 | { | |
574 | // | |
575 | // Set flag to make sure allocating memory without GUARD for page table | |
576 | // operation; otherwise infinite loops could be caused. | |
577 | // | |
578 | mOnGuarding = TRUE; | |
579 | // | |
580 | // Note: This might overwrite other attributes needed by other features, | |
581 | // such as memory protection (NX). Please make sure they are not enabled | |
582 | // at the same time. | |
583 | // | |
584 | gCpu->SetMemoryAttributes (gCpu, BaseAddress, EFI_PAGE_SIZE, EFI_MEMORY_RP); | |
585 | mOnGuarding = FALSE; | |
586 | } | |
587 | ||
588 | /** | |
589 | Unset the Guard page at the given address to the normal memory. | |
590 | ||
591 | This is done by changing the page table attribute to be PRSENT. | |
592 | ||
593 | @param[in] BaseAddress Page address to Guard at. | |
594 | ||
595 | @return VOID. | |
596 | **/ | |
597 | VOID | |
598 | EFIAPI | |
599 | UnsetGuardPage ( | |
600 | IN EFI_PHYSICAL_ADDRESS BaseAddress | |
601 | ) | |
602 | { | |
603 | // | |
604 | // Set flag to make sure allocating memory without GUARD for page table | |
605 | // operation; otherwise infinite loops could be caused. | |
606 | // | |
607 | mOnGuarding = TRUE; | |
608 | // | |
609 | // Note: This might overwrite other attributes needed by other features, | |
610 | // such as memory protection (NX). Please make sure they are not enabled | |
611 | // at the same time. | |
612 | // | |
613 | gCpu->SetMemoryAttributes (gCpu, BaseAddress, EFI_PAGE_SIZE, 0); | |
614 | mOnGuarding = FALSE; | |
615 | } | |
616 | ||
617 | /** | |
618 | Check to see if the memory at the given address should be guarded or not. | |
619 | ||
620 | @param[in] MemoryType Memory type to check. | |
621 | @param[in] AllocateType Allocation type to check. | |
622 | @param[in] PageOrPool Indicate a page allocation or pool allocation. | |
623 | ||
624 | ||
625 | @return TRUE The given type of memory should be guarded. | |
626 | @return FALSE The given type of memory should not be guarded. | |
627 | **/ | |
628 | BOOLEAN | |
629 | IsMemoryTypeToGuard ( | |
630 | IN EFI_MEMORY_TYPE MemoryType, | |
631 | IN EFI_ALLOCATE_TYPE AllocateType, | |
632 | IN UINT8 PageOrPool | |
633 | ) | |
634 | { | |
635 | UINT64 TestBit; | |
636 | UINT64 ConfigBit; | |
637 | BOOLEAN InSmm; | |
638 | ||
639 | if (gCpu == NULL || AllocateType == AllocateAddress) { | |
640 | return FALSE; | |
641 | } | |
642 | ||
643 | InSmm = FALSE; | |
644 | if (gSmmBase2 != NULL) { | |
645 | gSmmBase2->InSmm (gSmmBase2, &InSmm); | |
646 | } | |
647 | ||
648 | if (InSmm) { | |
649 | return FALSE; | |
650 | } | |
651 | ||
652 | if ((PcdGet8 (PcdHeapGuardPropertyMask) & PageOrPool) == 0) { | |
653 | return FALSE; | |
654 | } | |
655 | ||
656 | if (PageOrPool == GUARD_HEAP_TYPE_POOL) { | |
657 | ConfigBit = PcdGet64 (PcdHeapGuardPoolType); | |
658 | } else if (PageOrPool == GUARD_HEAP_TYPE_PAGE) { | |
659 | ConfigBit = PcdGet64 (PcdHeapGuardPageType); | |
660 | } else { | |
661 | ConfigBit = (UINT64)-1; | |
662 | } | |
663 | ||
664 | if ((UINT32)MemoryType >= MEMORY_TYPE_OS_RESERVED_MIN) { | |
665 | TestBit = BIT63; | |
666 | } else if ((UINT32) MemoryType >= MEMORY_TYPE_OEM_RESERVED_MIN) { | |
667 | TestBit = BIT62; | |
668 | } else if (MemoryType < EfiMaxMemoryType) { | |
669 | TestBit = LShiftU64 (1, MemoryType); | |
670 | } else if (MemoryType == EfiMaxMemoryType) { | |
671 | TestBit = (UINT64)-1; | |
672 | } else { | |
673 | TestBit = 0; | |
674 | } | |
675 | ||
676 | return ((ConfigBit & TestBit) != 0); | |
677 | } | |
678 | ||
679 | /** | |
680 | Check to see if the pool at the given address should be guarded or not. | |
681 | ||
682 | @param[in] MemoryType Pool type to check. | |
683 | ||
684 | ||
685 | @return TRUE The given type of pool should be guarded. | |
686 | @return FALSE The given type of pool should not be guarded. | |
687 | **/ | |
688 | BOOLEAN | |
689 | IsPoolTypeToGuard ( | |
690 | IN EFI_MEMORY_TYPE MemoryType | |
691 | ) | |
692 | { | |
693 | return IsMemoryTypeToGuard (MemoryType, AllocateAnyPages, | |
694 | GUARD_HEAP_TYPE_POOL); | |
695 | } | |
696 | ||
697 | /** | |
698 | Check to see if the page at the given address should be guarded or not. | |
699 | ||
700 | @param[in] MemoryType Page type to check. | |
701 | @param[in] AllocateType Allocation type to check. | |
702 | ||
703 | @return TRUE The given type of page should be guarded. | |
704 | @return FALSE The given type of page should not be guarded. | |
705 | **/ | |
706 | BOOLEAN | |
707 | IsPageTypeToGuard ( | |
708 | IN EFI_MEMORY_TYPE MemoryType, | |
709 | IN EFI_ALLOCATE_TYPE AllocateType | |
710 | ) | |
711 | { | |
712 | return IsMemoryTypeToGuard (MemoryType, AllocateType, GUARD_HEAP_TYPE_PAGE); | |
713 | } | |
714 | ||
715 | /** | |
716 | Set head Guard and tail Guard for the given memory range. | |
717 | ||
718 | @param[in] Memory Base address of memory to set guard for. | |
719 | @param[in] NumberOfPages Memory size in pages. | |
720 | ||
721 | @return VOID | |
722 | **/ | |
723 | VOID | |
724 | SetGuardForMemory ( | |
725 | IN EFI_PHYSICAL_ADDRESS Memory, | |
726 | IN UINTN NumberOfPages | |
727 | ) | |
728 | { | |
729 | EFI_PHYSICAL_ADDRESS GuardPage; | |
730 | ||
731 | // | |
732 | // Set tail Guard | |
733 | // | |
734 | GuardPage = Memory + EFI_PAGES_TO_SIZE (NumberOfPages); | |
735 | if (!IsGuardPage (GuardPage)) { | |
736 | SetGuardPage (GuardPage); | |
737 | } | |
738 | ||
739 | // Set head Guard | |
740 | GuardPage = Memory - EFI_PAGES_TO_SIZE (1); | |
741 | if (!IsGuardPage (GuardPage)) { | |
742 | SetGuardPage (GuardPage); | |
743 | } | |
744 | ||
745 | // | |
746 | // Mark the memory range as Guarded | |
747 | // | |
748 | SetGuardedMemoryBits (Memory, NumberOfPages); | |
749 | } | |
750 | ||
751 | /** | |
752 | Unset head Guard and tail Guard for the given memory range. | |
753 | ||
754 | @param[in] Memory Base address of memory to unset guard for. | |
755 | @param[in] NumberOfPages Memory size in pages. | |
756 | ||
757 | @return VOID | |
758 | **/ | |
759 | VOID | |
760 | UnsetGuardForMemory ( | |
761 | IN EFI_PHYSICAL_ADDRESS Memory, | |
762 | IN UINTN NumberOfPages | |
763 | ) | |
764 | { | |
765 | EFI_PHYSICAL_ADDRESS GuardPage; | |
766 | ||
767 | if (NumberOfPages == 0) { | |
768 | return; | |
769 | } | |
770 | ||
771 | // | |
772 | // Head Guard must be one page before, if any. | |
773 | // | |
774 | GuardPage = Memory - EFI_PAGES_TO_SIZE (1); | |
775 | if (IsHeadGuard (GuardPage)) { | |
776 | if (!IsMemoryGuarded (GuardPage - EFI_PAGES_TO_SIZE (1))) { | |
777 | // | |
778 | // If the head Guard is not a tail Guard of adjacent memory block, | |
779 | // unset it. | |
780 | // | |
781 | UnsetGuardPage (GuardPage); | |
782 | } | |
783 | } else if (IsMemoryGuarded (GuardPage)) { | |
784 | // | |
785 | // Pages before memory to free are still in Guard. It's a partial free | |
786 | // case. Turn first page of memory block to free into a new Guard. | |
787 | // | |
788 | SetGuardPage (Memory); | |
789 | } | |
790 | ||
791 | // | |
792 | // Tail Guard must be the page after this memory block to free, if any. | |
793 | // | |
794 | GuardPage = Memory + EFI_PAGES_TO_SIZE (NumberOfPages); | |
795 | if (IsTailGuard (GuardPage)) { | |
796 | if (!IsMemoryGuarded (GuardPage + EFI_PAGES_TO_SIZE (1))) { | |
797 | // | |
798 | // If the tail Guard is not a head Guard of adjacent memory block, | |
799 | // free it; otherwise, keep it. | |
800 | // | |
801 | UnsetGuardPage (GuardPage); | |
802 | } | |
803 | } else if (IsMemoryGuarded (GuardPage)) { | |
804 | // | |
805 | // Pages after memory to free are still in Guard. It's a partial free | |
806 | // case. We need to keep one page to be a head Guard. | |
807 | // | |
808 | SetGuardPage (GuardPage - EFI_PAGES_TO_SIZE (1)); | |
809 | } | |
810 | ||
811 | // | |
812 | // No matter what, we just clear the mark of the Guarded memory. | |
813 | // | |
814 | ClearGuardedMemoryBits(Memory, NumberOfPages); | |
815 | } | |
816 | ||
817 | /** | |
818 | Adjust address of free memory according to existing and/or required Guard. | |
819 | ||
820 | This function will check if there're existing Guard pages of adjacent | |
821 | memory blocks, and try to use it as the Guard page of the memory to be | |
822 | allocated. | |
823 | ||
824 | @param[in] Start Start address of free memory block. | |
825 | @param[in] Size Size of free memory block. | |
826 | @param[in] SizeRequested Size of memory to allocate. | |
827 | ||
828 | @return The end address of memory block found. | |
829 | @return 0 if no enough space for the required size of memory and its Guard. | |
830 | **/ | |
831 | UINT64 | |
832 | AdjustMemoryS ( | |
833 | IN UINT64 Start, | |
834 | IN UINT64 Size, | |
835 | IN UINT64 SizeRequested | |
836 | ) | |
837 | { | |
838 | UINT64 Target; | |
839 | ||
840 | Target = Start + Size - SizeRequested; | |
841 | ||
842 | // | |
843 | // At least one more page needed for Guard page. | |
844 | // | |
845 | if (Size < (SizeRequested + EFI_PAGES_TO_SIZE (1))) { | |
846 | return 0; | |
847 | } | |
848 | ||
849 | if (!IsGuardPage (Start + Size)) { | |
850 | // No Guard at tail to share. One more page is needed. | |
851 | Target -= EFI_PAGES_TO_SIZE (1); | |
852 | } | |
853 | ||
854 | // Out of range? | |
855 | if (Target < Start) { | |
856 | return 0; | |
857 | } | |
858 | ||
859 | // At the edge? | |
860 | if (Target == Start) { | |
861 | if (!IsGuardPage (Target - EFI_PAGES_TO_SIZE (1))) { | |
862 | // No enough space for a new head Guard if no Guard at head to share. | |
863 | return 0; | |
864 | } | |
865 | } | |
866 | ||
867 | // OK, we have enough pages for memory and its Guards. Return the End of the | |
868 | // free space. | |
869 | return Target + SizeRequested - 1; | |
870 | } | |
871 | ||
872 | /** | |
873 | Adjust the start address and number of pages to free according to Guard. | |
874 | ||
875 | The purpose of this function is to keep the shared Guard page with adjacent | |
876 | memory block if it's still in guard, or free it if no more sharing. Another | |
877 | is to reserve pages as Guard pages in partial page free situation. | |
878 | ||
879 | @param[in,out] Memory Base address of memory to free. | |
880 | @param[in,out] NumberOfPages Size of memory to free. | |
881 | ||
882 | @return VOID. | |
883 | **/ | |
884 | VOID | |
885 | AdjustMemoryF ( | |
886 | IN OUT EFI_PHYSICAL_ADDRESS *Memory, | |
887 | IN OUT UINTN *NumberOfPages | |
888 | ) | |
889 | { | |
890 | EFI_PHYSICAL_ADDRESS Start; | |
891 | EFI_PHYSICAL_ADDRESS MemoryToTest; | |
892 | UINTN PagesToFree; | |
893 | ||
894 | if (Memory == NULL || NumberOfPages == NULL || *NumberOfPages == 0) { | |
895 | return; | |
896 | } | |
897 | ||
898 | Start = *Memory; | |
899 | PagesToFree = *NumberOfPages; | |
900 | ||
901 | // | |
902 | // Head Guard must be one page before, if any. | |
903 | // | |
904 | MemoryToTest = Start - EFI_PAGES_TO_SIZE (1); | |
905 | if (IsHeadGuard (MemoryToTest)) { | |
906 | if (!IsMemoryGuarded (MemoryToTest - EFI_PAGES_TO_SIZE (1))) { | |
907 | // | |
908 | // If the head Guard is not a tail Guard of adjacent memory block, | |
909 | // free it; otherwise, keep it. | |
910 | // | |
911 | Start -= EFI_PAGES_TO_SIZE (1); | |
912 | PagesToFree += 1; | |
913 | } | |
914 | } else if (IsMemoryGuarded (MemoryToTest)) { | |
915 | // | |
916 | // Pages before memory to free are still in Guard. It's a partial free | |
917 | // case. We need to keep one page to be a tail Guard. | |
918 | // | |
919 | Start += EFI_PAGES_TO_SIZE (1); | |
920 | PagesToFree -= 1; | |
921 | } | |
922 | ||
923 | // | |
924 | // Tail Guard must be the page after this memory block to free, if any. | |
925 | // | |
926 | MemoryToTest = Start + EFI_PAGES_TO_SIZE (PagesToFree); | |
927 | if (IsTailGuard (MemoryToTest)) { | |
928 | if (!IsMemoryGuarded (MemoryToTest + EFI_PAGES_TO_SIZE (1))) { | |
929 | // | |
930 | // If the tail Guard is not a head Guard of adjacent memory block, | |
931 | // free it; otherwise, keep it. | |
932 | // | |
933 | PagesToFree += 1; | |
934 | } | |
935 | } else if (IsMemoryGuarded (MemoryToTest)) { | |
936 | // | |
937 | // Pages after memory to free are still in Guard. It's a partial free | |
938 | // case. We need to keep one page to be a head Guard. | |
939 | // | |
940 | PagesToFree -= 1; | |
941 | } | |
942 | ||
943 | *Memory = Start; | |
944 | *NumberOfPages = PagesToFree; | |
945 | } | |
946 | ||
947 | /** | |
948 | Adjust the base and number of pages to really allocate according to Guard. | |
949 | ||
950 | @param[in,out] Memory Base address of free memory. | |
951 | @param[in,out] NumberOfPages Size of memory to allocate. | |
952 | ||
953 | @return VOID. | |
954 | **/ | |
955 | VOID | |
956 | AdjustMemoryA ( | |
957 | IN OUT EFI_PHYSICAL_ADDRESS *Memory, | |
958 | IN OUT UINTN *NumberOfPages | |
959 | ) | |
960 | { | |
961 | // | |
962 | // FindFreePages() has already taken the Guard into account. It's safe to | |
963 | // adjust the start address and/or number of pages here, to make sure that | |
964 | // the Guards are also "allocated". | |
965 | // | |
966 | if (!IsGuardPage (*Memory + EFI_PAGES_TO_SIZE (*NumberOfPages))) { | |
967 | // No tail Guard, add one. | |
968 | *NumberOfPages += 1; | |
969 | } | |
970 | ||
971 | if (!IsGuardPage (*Memory - EFI_PAGE_SIZE)) { | |
972 | // No head Guard, add one. | |
973 | *Memory -= EFI_PAGE_SIZE; | |
974 | *NumberOfPages += 1; | |
975 | } | |
976 | } | |
977 | ||
978 | /** | |
979 | Adjust the pool head position to make sure the Guard page is adjavent to | |
980 | pool tail or pool head. | |
981 | ||
982 | @param[in] Memory Base address of memory allocated. | |
983 | @param[in] NoPages Number of pages actually allocated. | |
984 | @param[in] Size Size of memory requested. | |
985 | (plus pool head/tail overhead) | |
986 | ||
987 | @return Address of pool head. | |
988 | **/ | |
989 | VOID * | |
990 | AdjustPoolHeadA ( | |
991 | IN EFI_PHYSICAL_ADDRESS Memory, | |
992 | IN UINTN NoPages, | |
993 | IN UINTN Size | |
994 | ) | |
995 | { | |
996 | if ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) != 0) { | |
997 | // | |
998 | // Pool head is put near the head Guard | |
999 | // | |
1000 | return (VOID *)(UINTN)Memory; | |
1001 | } | |
1002 | ||
1003 | // | |
1004 | // Pool head is put near the tail Guard | |
1005 | // | |
1006 | return (VOID *)(UINTN)(Memory + EFI_PAGES_TO_SIZE (NoPages) - Size); | |
1007 | } | |
1008 | ||
1009 | /** | |
1010 | Get the page base address according to pool head address. | |
1011 | ||
1012 | @param[in] Memory Head address of pool to free. | |
1013 | ||
1014 | @return Address of pool head. | |
1015 | **/ | |
1016 | VOID * | |
1017 | AdjustPoolHeadF ( | |
1018 | IN EFI_PHYSICAL_ADDRESS Memory | |
1019 | ) | |
1020 | { | |
1021 | if ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) != 0) { | |
1022 | // | |
1023 | // Pool head is put near the head Guard | |
1024 | // | |
1025 | return (VOID *)(UINTN)Memory; | |
1026 | } | |
1027 | ||
1028 | // | |
1029 | // Pool head is put near the tail Guard | |
1030 | // | |
1031 | return (VOID *)(UINTN)(Memory & ~EFI_PAGE_MASK); | |
1032 | } | |
1033 | ||
1034 | /** | |
1035 | Allocate or free guarded memory. | |
1036 | ||
1037 | @param[in] Start Start address of memory to allocate or free. | |
1038 | @param[in] NumberOfPages Memory size in pages. | |
1039 | @param[in] NewType Memory type to convert to. | |
1040 | ||
1041 | @return VOID. | |
1042 | **/ | |
1043 | EFI_STATUS | |
1044 | CoreConvertPagesWithGuard ( | |
1045 | IN UINT64 Start, | |
1046 | IN UINTN NumberOfPages, | |
1047 | IN EFI_MEMORY_TYPE NewType | |
1048 | ) | |
1049 | { | |
1050 | if (NewType == EfiConventionalMemory) { | |
1051 | AdjustMemoryF (&Start, &NumberOfPages); | |
1052 | } else { | |
1053 | AdjustMemoryA (&Start, &NumberOfPages); | |
1054 | } | |
1055 | ||
1056 | return CoreConvertPages(Start, NumberOfPages, NewType); | |
1057 | } | |
1058 | ||
1059 | /** | |
1060 | Helper function to convert a UINT64 value in binary to a string. | |
1061 | ||
1062 | @param[in] Value Value of a UINT64 integer. | |
1063 | @param[out] BinString String buffer to contain the conversion result. | |
1064 | ||
1065 | @return VOID. | |
1066 | **/ | |
1067 | VOID | |
1068 | Uint64ToBinString ( | |
1069 | IN UINT64 Value, | |
1070 | OUT CHAR8 *BinString | |
1071 | ) | |
1072 | { | |
1073 | UINTN Index; | |
1074 | ||
1075 | if (BinString == NULL) { | |
1076 | return; | |
1077 | } | |
1078 | ||
1079 | for (Index = 64; Index > 0; --Index) { | |
1080 | BinString[Index - 1] = '0' + (Value & 1); | |
1081 | Value = RShiftU64 (Value, 1); | |
1082 | } | |
1083 | BinString[64] = '\0'; | |
1084 | } | |
1085 | ||
1086 | /** | |
1087 | Dump the guarded memory bit map. | |
1088 | **/ | |
1089 | VOID | |
1090 | EFIAPI | |
1091 | DumpGuardedMemoryBitmap ( | |
1092 | VOID | |
1093 | ) | |
1094 | { | |
1095 | UINTN Entries[GUARDED_HEAP_MAP_TABLE_DEPTH]; | |
1096 | UINTN Shifts[GUARDED_HEAP_MAP_TABLE_DEPTH]; | |
1097 | UINTN Indices[GUARDED_HEAP_MAP_TABLE_DEPTH]; | |
1098 | UINT64 Tables[GUARDED_HEAP_MAP_TABLE_DEPTH]; | |
1099 | UINT64 Addresses[GUARDED_HEAP_MAP_TABLE_DEPTH]; | |
1100 | UINT64 TableEntry; | |
1101 | UINT64 Address; | |
1102 | INTN Level; | |
1103 | UINTN RepeatZero; | |
1104 | CHAR8 String[GUARDED_HEAP_MAP_ENTRY_BITS + 1]; | |
1105 | CHAR8 *Ruler1; | |
1106 | CHAR8 *Ruler2; | |
1107 | ||
1108 | if (mGuardedMemoryMap == 0) { | |
1109 | return; | |
1110 | } | |
1111 | ||
1112 | Ruler1 = " 3 2 1 0"; | |
1113 | Ruler2 = "FEDCBA9876543210FEDCBA9876543210FEDCBA9876543210FEDCBA9876543210"; | |
1114 | ||
1115 | DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "=============================" | |
1116 | " Guarded Memory Bitmap " | |
1117 | "==============================\r\n")); | |
1118 | DEBUG ((HEAP_GUARD_DEBUG_LEVEL, " %a\r\n", Ruler1)); | |
1119 | DEBUG ((HEAP_GUARD_DEBUG_LEVEL, " %a\r\n", Ruler2)); | |
1120 | ||
1121 | CopyMem (Entries, mLevelMask, sizeof (Entries)); | |
1122 | CopyMem (Shifts, mLevelShift, sizeof (Shifts)); | |
1123 | ||
1124 | SetMem (Indices, sizeof(Indices), 0); | |
1125 | SetMem (Tables, sizeof(Tables), 0); | |
1126 | SetMem (Addresses, sizeof(Addresses), 0); | |
1127 | ||
1128 | Level = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel; | |
1129 | Tables[Level] = mGuardedMemoryMap; | |
1130 | Address = 0; | |
1131 | RepeatZero = 0; | |
1132 | ||
1133 | while (TRUE) { | |
1134 | if (Indices[Level] > Entries[Level]) { | |
1135 | ||
1136 | Tables[Level] = 0; | |
1137 | Level -= 1; | |
1138 | RepeatZero = 0; | |
1139 | ||
1140 | DEBUG (( | |
1141 | HEAP_GUARD_DEBUG_LEVEL, | |
1142 | "=========================================" | |
1143 | "=========================================\r\n" | |
1144 | )); | |
1145 | ||
1146 | } else { | |
1147 | ||
1148 | TableEntry = ((UINT64 *)(UINTN)Tables[Level])[Indices[Level]]; | |
1149 | Address = Addresses[Level]; | |
1150 | ||
1151 | if (TableEntry == 0) { | |
1152 | ||
1153 | if (Level == GUARDED_HEAP_MAP_TABLE_DEPTH - 1) { | |
1154 | if (RepeatZero == 0) { | |
1155 | Uint64ToBinString(TableEntry, String); | |
1156 | DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "%016lx: %a\r\n", Address, String)); | |
1157 | } else if (RepeatZero == 1) { | |
1158 | DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "... : ...\r\n")); | |
1159 | } | |
1160 | RepeatZero += 1; | |
1161 | } | |
1162 | ||
1163 | } else if (Level < GUARDED_HEAP_MAP_TABLE_DEPTH - 1) { | |
1164 | ||
1165 | Level += 1; | |
1166 | Tables[Level] = TableEntry; | |
1167 | Addresses[Level] = Address; | |
1168 | Indices[Level] = 0; | |
1169 | RepeatZero = 0; | |
1170 | ||
1171 | continue; | |
1172 | ||
1173 | } else { | |
1174 | ||
1175 | RepeatZero = 0; | |
1176 | Uint64ToBinString(TableEntry, String); | |
1177 | DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "%016lx: %a\r\n", Address, String)); | |
1178 | ||
1179 | } | |
1180 | } | |
1181 | ||
1182 | if (Level < (GUARDED_HEAP_MAP_TABLE_DEPTH - (INTN)mMapLevel)) { | |
1183 | break; | |
1184 | } | |
1185 | ||
1186 | Indices[Level] += 1; | |
1187 | Address = (Level == 0) ? 0 : Addresses[Level - 1]; | |
1188 | Addresses[Level] = Address | LShiftU64(Indices[Level], Shifts[Level]); | |
1189 | ||
1190 | } | |
1191 | } | |
1192 |