1 /*
2 * FreeLoader
3 * Copyright (C) 2006-2008 Aleksey Bragin <aleksey@reactos.org>
4 * Copyright (C) 2006-2009 Hervé Poussineau <hpoussin@reactos.org>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License along
17 * with this program; if not, write to the Free Software Foundation, Inc.,
18 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
19 */
20
21 #include <freeldr.h>
22
23 #include <debug.h>
24 DBG_DEFAULT_CHANNEL(MEMORY);
25
26 PVOID PageLookupTableAddress = NULL;
27 PFN_NUMBER TotalPagesInLookupTable = 0;
28 PFN_NUMBER FreePagesInLookupTable = 0;
29 PFN_NUMBER LastFreePageHint = 0;
30 PFN_NUMBER MmLowestPhysicalPage = 0xFFFFFFFF;
31 PFN_NUMBER MmHighestPhysicalPage = 0;
32
33 PFREELDR_MEMORY_DESCRIPTOR BiosMemoryMap;
34 ULONG BiosMemoryMapEntryCount;
35 SIZE_T FrLdrImageSize;
36
37 #if DBG
38 typedef struct
39 {
40 TYPE_OF_MEMORY Type;
41 PCSTR TypeString;
42 } FREELDR_MEMORY_TYPE, *PFREELDR_MEMORY_TYPE;
43
44 FREELDR_MEMORY_TYPE MemoryTypeArray[] =
45 {
46 { LoaderMaximum, "Unknown memory" },
47 { LoaderFree, "Free memory" },
48 { LoaderBad, "Bad memory" },
49 { LoaderLoadedProgram, "LoadedProgram" },
50 { LoaderFirmwareTemporary, "FirmwareTemporary" },
51 { LoaderFirmwarePermanent, "FirmwarePermanent" },
52 { LoaderOsloaderHeap, "OsloaderHeap" },
53 { LoaderOsloaderStack, "OsloaderStack" },
54 { LoaderSystemCode, "SystemCode" },
55 { LoaderHalCode, "HalCode" },
56 { LoaderBootDriver, "BootDriver" },
57 { LoaderRegistryData, "RegistryData" },
58 { LoaderMemoryData, "MemoryData" },
59 { LoaderNlsData, "NlsData" },
60 { LoaderSpecialMemory, "SpecialMemory" },
61 { LoaderReserve, "Reserve" },
62 };
63 ULONG MemoryTypeCount = sizeof(MemoryTypeArray) / sizeof(MemoryTypeArray[0]);
64
65 PCSTR
MmGetSystemMemoryMapTypeString(TYPE_OF_MEMORY Type)66 MmGetSystemMemoryMapTypeString(
67 TYPE_OF_MEMORY Type)
68 {
69 ULONG Index;
70
71 for (Index = 1; Index < MemoryTypeCount; Index++)
72 {
73 if (MemoryTypeArray[Index].Type == Type)
74 {
75 return MemoryTypeArray[Index].TypeString;
76 }
77 }
78
79 return MemoryTypeArray[0].TypeString;
80 }
81
82 VOID
DbgDumpMemoryMap(PFREELDR_MEMORY_DESCRIPTOR List)83 DbgDumpMemoryMap(
84 PFREELDR_MEMORY_DESCRIPTOR List)
85 {
86 ULONG i;
87
88 DbgPrint("Dumping Memory map:\n");
89 for (i = 0; List[i].PageCount != 0; i++)
90 {
91 DbgPrint("%02d %08x - %08x: %s\n",
92 i,
93 List[i].BasePage * PAGE_SIZE,
94 (List[i].BasePage + List[i].PageCount) * PAGE_SIZE,
95 MmGetSystemMemoryMapTypeString(List[i].MemoryType));
96 }
97 DbgPrint("\n");
98 }
99 #endif
100
101 ULONG
AddMemoryDescriptor(IN OUT PFREELDR_MEMORY_DESCRIPTOR List,IN ULONG MaxCount,IN PFN_NUMBER BasePage,IN PFN_NUMBER PageCount,IN TYPE_OF_MEMORY MemoryType)102 AddMemoryDescriptor(
103 IN OUT PFREELDR_MEMORY_DESCRIPTOR List,
104 IN ULONG MaxCount,
105 IN PFN_NUMBER BasePage,
106 IN PFN_NUMBER PageCount,
107 IN TYPE_OF_MEMORY MemoryType)
108 {
109 ULONG Index, DescriptCount;
110 PFN_NUMBER EndPage;
111 TRACE("AddMemoryDescriptor(0x%Ix, 0x%Ix, %u)\n",
112 BasePage, PageCount, MemoryType);
113
114 EndPage = BasePage + PageCount;
115
116 /* Skip over all descriptor below the new range */
117 Index = 0;
118 while ((List[Index].PageCount != 0) &&
119 ((List[Index].BasePage + List[Index].PageCount) <= BasePage))
120 {
121 Index++;
122 }
123
124 /* Count the descriptors */
125 DescriptCount = Index;
126 while (List[DescriptCount].PageCount != 0)
127 {
128 DescriptCount++;
129 }
130
131 /* Check if the existing range conflicts with the new range */
132 while ((List[Index].PageCount != 0) &&
133 (List[Index].BasePage < EndPage))
134 {
135 TRACE("AddMemoryDescriptor conflict @%lu: new=[%lx:%lx], existing=[%lx,%lx]\n",
136 Index, BasePage, PageCount, List[Index].BasePage, List[Index].PageCount);
137
138 /*
139 * We have 4 overlapping cases:
140 *
141 * Case (a) (b) (c) (d)
142 * Existing range |---| |-----| |---| |---|
143 * New range |---| |---| |-----| |---|
144 *
145 */
146
147 /* Check if the existing range starts before the new range (a)/(b) */
148 if (List[Index].BasePage < BasePage)
149 {
150 /* Check if the existing range extends beyond the new range (b) */
151 if (List[Index].BasePage + List[Index].PageCount > EndPage)
152 {
153 /* Split the descriptor */
154 RtlMoveMemory(&List[Index + 1],
155 &List[Index],
156 (DescriptCount - Index) * sizeof(List[0]));
157 List[Index + 1].BasePage = EndPage;
158 List[Index + 1].PageCount = List[Index].BasePage +
159 List[Index].PageCount -
160 List[Index + 1].BasePage;
161 List[Index].PageCount = BasePage - List[Index].BasePage;
162 Index++;
163 DescriptCount++;
164 break;
165 }
166 else
167 {
168 /* Crop the existing range and continue with the next range */
169 List[Index].PageCount = BasePage - List[Index].BasePage;
170 Index++;
171 }
172 }
173 /* Check if the existing range is fully covered by the new range (c) */
174 else if ((List[Index].BasePage + List[Index].PageCount) <=
175 EndPage)
176 {
177 /* Delete this descriptor */
178 RtlMoveMemory(&List[Index],
179 &List[Index + 1],
180 (DescriptCount - Index) * sizeof(List[0]));
181 DescriptCount--;
182 }
183 /* Otherwise the existing range ends after the new range (d) */
184 else
185 {
186 /* Crop the existing range at the start and bail out */
187 List[Index].PageCount -= EndPage - List[Index].BasePage;
188 List[Index].BasePage = EndPage;
189 break;
190 }
191 }
192
193 /* Make sure we can still add a new descriptor */
194 if (DescriptCount >= MaxCount)
195 {
196 FrLdrBugCheckWithMessage(
197 MEMORY_INIT_FAILURE,
198 __FILE__,
199 __LINE__,
200 "Ran out of static memory descriptors!");
201 }
202
203 /* Insert the new descriptor */
204 if (Index < DescriptCount)
205 {
206 RtlMoveMemory(&List[Index + 1],
207 &List[Index],
208 (DescriptCount - Index) * sizeof(List[0]));
209 }
210
211 List[Index].BasePage = BasePage;
212 List[Index].PageCount = PageCount;
213 List[Index].MemoryType = MemoryType;
214 DescriptCount++;
215
216 #if 0 // only enable on demand!
217 DbgDumpMemoryMap(List);
218 #endif
219 return DescriptCount;
220 }
221
222 const FREELDR_MEMORY_DESCRIPTOR*
ArcGetMemoryDescriptor(const FREELDR_MEMORY_DESCRIPTOR * Current)223 ArcGetMemoryDescriptor(const FREELDR_MEMORY_DESCRIPTOR* Current)
224 {
225 if (Current == NULL)
226 {
227 return BiosMemoryMap;
228 }
229 else
230 {
231 Current++;
232 if (Current->PageCount == 0) return NULL;
233 return Current;
234 }
235 }
236
237 static
238 VOID
MmCheckFreeldrImageFile(VOID)239 MmCheckFreeldrImageFile(VOID)
240 {
241 #ifndef UEFIBOOT
242 PIMAGE_NT_HEADERS NtHeaders;
243 PIMAGE_FILE_HEADER FileHeader;
244 PIMAGE_OPTIONAL_HEADER OptionalHeader;
245
246 /* Get the NT headers */
247 NtHeaders = RtlImageNtHeader(&__ImageBase);
248 if (!NtHeaders)
249 {
250 ERR("Could not get NtHeaders!\n");
251 FrLdrBugCheckWithMessage(
252 FREELDR_IMAGE_CORRUPTION,
253 __FILE__,
254 __LINE__,
255 "Could not get NtHeaders!\n");
256 }
257
258 /* Check the file header */
259 FileHeader = &NtHeaders->FileHeader;
260 if ((FileHeader->Machine != IMAGE_FILE_MACHINE_NATIVE) ||
261 (FileHeader->NumberOfSections != FREELDR_SECTION_COUNT) ||
262 (FileHeader->PointerToSymbolTable != 0) || // Symbols stripped
263 (FileHeader->NumberOfSymbols != 0) || // "" ""
264 (FileHeader->SizeOfOptionalHeader != sizeof(IMAGE_OPTIONAL_HEADER)))
265 {
266 ERR("FreeLdr FileHeader is invalid.\n");
267 FrLdrBugCheckWithMessage(
268 FREELDR_IMAGE_CORRUPTION,
269 __FILE__,
270 __LINE__,
271 "FreeLdr FileHeader is invalid.\n"
272 "Machine == 0x%lx, expected 0x%lx\n"
273 "NumberOfSections == 0x%lx, expected 0x%lx\n"
274 "PointerToSymbolTable == 0x%lx, expected 0\n"
275 "NumberOfSymbols == 0x%lx, expected 0\n"
276 "SizeOfOptionalHeader == 0x%lx, expected 0x%lx\n",
277 FileHeader->Machine, IMAGE_FILE_MACHINE_NATIVE,
278 FileHeader->NumberOfSections, FREELDR_SECTION_COUNT,
279 FileHeader->PointerToSymbolTable,
280 FileHeader->NumberOfSymbols,
281 FileHeader->SizeOfOptionalHeader, sizeof(IMAGE_OPTIONAL_HEADER));
282 }
283
284 /* Check the optional header */
285 OptionalHeader = &NtHeaders->OptionalHeader;
286 if ((OptionalHeader->Magic != IMAGE_NT_OPTIONAL_HDR_MAGIC) ||
287 (OptionalHeader->Subsystem != IMAGE_SUBSYSTEM_NATIVE) ||
288 (OptionalHeader->ImageBase != FREELDR_PE_BASE) ||
289 (OptionalHeader->SizeOfImage > MAX_FREELDR_PE_SIZE) ||
290 (OptionalHeader->SectionAlignment != OptionalHeader->FileAlignment))
291 {
292 ERR("FreeLdr OptionalHeader is invalid.\n");
293 FrLdrBugCheckWithMessage(
294 FREELDR_IMAGE_CORRUPTION,
295 __FILE__,
296 __LINE__,
297 "FreeLdr OptionalHeader is invalid.\n"
298 "Magic == 0x%lx, expected 0x%lx\n"
299 "Subsystem == 0x%lx, expected 1 (native)\n"
300 "ImageBase == 0x%lx, expected 0x%lx\n"
301 "SizeOfImage == 0x%lx, maximum 0x%lx\n"
302 "SectionAlignment 0x%lx doesn't match FileAlignment 0x%lx\n",
303 OptionalHeader->Magic, IMAGE_NT_OPTIONAL_HDR_MAGIC,
304 OptionalHeader->Subsystem,
305 OptionalHeader->ImageBase, FREELDR_PE_BASE,
306 OptionalHeader->SizeOfImage, MAX_FREELDR_PE_SIZE,
307 OptionalHeader->SectionAlignment, OptionalHeader->FileAlignment);
308 }
309
310 /* Calculate the full image size */
311 FrLdrImageSize = (ULONG_PTR)&__ImageBase + OptionalHeader->SizeOfImage - FREELDR_BASE;
312 #endif
313 }
314
MmInitializeMemoryManager(VOID)315 BOOLEAN MmInitializeMemoryManager(VOID)
316 {
317 #if DBG
318 const FREELDR_MEMORY_DESCRIPTOR* MemoryDescriptor = NULL;
319 #endif
320
321 TRACE("Initializing Memory Manager.\n");
322
323 /* Check the freeldr binary */
324 MmCheckFreeldrImageFile();
325
326 BiosMemoryMap = MachVtbl.GetMemoryMap(&BiosMemoryMapEntryCount);
327
328 #if DBG
329 // Dump the system memory map
330 TRACE("System Memory Map (Base Address, Length, Type):\n");
331 while ((MemoryDescriptor = ArcGetMemoryDescriptor(MemoryDescriptor)) != NULL)
332 {
333 TRACE("%x\t %x\t %s\n",
334 MemoryDescriptor->BasePage * MM_PAGE_SIZE,
335 MemoryDescriptor->PageCount * MM_PAGE_SIZE,
336 MmGetSystemMemoryMapTypeString(MemoryDescriptor->MemoryType));
337 }
338 #endif
339
340 // Find address for the page lookup table
341 TotalPagesInLookupTable = MmGetAddressablePageCountIncludingHoles();
342 PageLookupTableAddress = MmFindLocationForPageLookupTable(TotalPagesInLookupTable);
343 LastFreePageHint = MmHighestPhysicalPage;
344
345 if (PageLookupTableAddress == 0)
346 {
347 // If we get here then we probably couldn't
348 // find a contiguous chunk of memory big
349 // enough to hold the page lookup table
350 printf("Error initializing memory manager!\n");
351 return FALSE;
352 }
353
354 // Initialize the page lookup table
355 MmInitPageLookupTable(PageLookupTableAddress, TotalPagesInLookupTable);
356
357 MmUpdateLastFreePageHint(PageLookupTableAddress, TotalPagesInLookupTable);
358
359 FreePagesInLookupTable = MmCountFreePagesInLookupTable(PageLookupTableAddress,
360 TotalPagesInLookupTable);
361
362 MmInitializeHeap(PageLookupTableAddress);
363
364 TRACE("Memory Manager initialized. 0x%x pages available.\n", FreePagesInLookupTable);
365
366
367 return TRUE;
368 }
369
370
MmGetPageNumberFromAddress(PVOID Address)371 PFN_NUMBER MmGetPageNumberFromAddress(PVOID Address)
372 {
373 return ((ULONG_PTR)Address) / MM_PAGE_SIZE;
374 }
375
MmGetAddressablePageCountIncludingHoles(VOID)376 PFN_NUMBER MmGetAddressablePageCountIncludingHoles(VOID)
377 {
378 const FREELDR_MEMORY_DESCRIPTOR* MemoryDescriptor = NULL;
379 PFN_NUMBER PageCount;
380
381 //
382 // Go through the whole memory map to get max address
383 //
384 while ((MemoryDescriptor = ArcGetMemoryDescriptor(MemoryDescriptor)) != NULL)
385 {
386 //
387 // Check if we got a higher end page address
388 //
389 if (MemoryDescriptor->BasePage + MemoryDescriptor->PageCount > MmHighestPhysicalPage)
390 {
391 //
392 // Yes, remember it if this is real memory
393 //
394 if (MemoryDescriptor->MemoryType == LoaderFree)
395 MmHighestPhysicalPage = MemoryDescriptor->BasePage + MemoryDescriptor->PageCount;
396 }
397
398 //
399 // Check if we got a higher (usable) start page address
400 //
401 if (MemoryDescriptor->BasePage < MmLowestPhysicalPage)
402 {
403 //
404 // Yes, remember it if this is real memory
405 //
406 MmLowestPhysicalPage = MemoryDescriptor->BasePage;
407 }
408 }
409
410 TRACE("lo/hi %lx %lx\n", MmLowestPhysicalPage, MmHighestPhysicalPage);
411 PageCount = MmHighestPhysicalPage - MmLowestPhysicalPage;
412 TRACE("MmGetAddressablePageCountIncludingHoles() returning 0x%x\n", PageCount);
413 return PageCount;
414 }
415
MmFindLocationForPageLookupTable(PFN_NUMBER TotalPageCount)416 PVOID MmFindLocationForPageLookupTable(PFN_NUMBER TotalPageCount)
417 {
418 const FREELDR_MEMORY_DESCRIPTOR* MemoryDescriptor = NULL;
419 SIZE_T PageLookupTableSize;
420 PFN_NUMBER RequiredPages;
421 PFN_NUMBER CandidateBasePage = 0;
422 PFN_NUMBER CandidatePageCount = 0;
423 PFN_NUMBER PageLookupTableEndPage;
424 PVOID PageLookupTableMemAddress;
425
426 // Calculate how much pages we need to keep the page lookup table
427 PageLookupTableSize = TotalPageCount * sizeof(PAGE_LOOKUP_TABLE_ITEM);
428 RequiredPages = PageLookupTableSize / MM_PAGE_SIZE;
429
430 // Search the highest memory block big enough to contain lookup table
431 while ((MemoryDescriptor = ArcGetMemoryDescriptor(MemoryDescriptor)) != NULL)
432 {
433 // Continue, if memory is not free
434 if (MemoryDescriptor->MemoryType != LoaderFree) continue;
435
436 // Continue, if the block is not big enough
437 if (MemoryDescriptor->PageCount < RequiredPages) continue;
438
439 // Continue, if it is not at a higher address than previous address
440 if (MemoryDescriptor->BasePage < CandidateBasePage) continue;
441
442 // Continue, if the address is too high
443 if (MemoryDescriptor->BasePage + RequiredPages >= MM_MAX_PAGE_LOADER) continue;
444
445 // Memory block is more suitable than the previous one
446 CandidateBasePage = MemoryDescriptor->BasePage;
447 CandidatePageCount = MemoryDescriptor->PageCount;
448 }
449
450 // Calculate the end address for the lookup table
451 PageLookupTableEndPage = min(CandidateBasePage + CandidatePageCount,
452 MM_MAX_PAGE_LOADER);
453
454 // Calculate the virtual address
455 PageLookupTableMemAddress = (PVOID)((PageLookupTableEndPage * PAGE_SIZE)
456 - PageLookupTableSize);
457
458 TRACE("MmFindLocationForPageLookupTable() returning 0x%x\n", PageLookupTableMemAddress);
459
460 return PageLookupTableMemAddress;
461 }
462
MmInitPageLookupTable(PVOID PageLookupTable,PFN_NUMBER TotalPageCount)463 VOID MmInitPageLookupTable(PVOID PageLookupTable, PFN_NUMBER TotalPageCount)
464 {
465 const FREELDR_MEMORY_DESCRIPTOR* MemoryDescriptor = NULL;
466 PFN_NUMBER PageLookupTableStartPage;
467 PFN_NUMBER PageLookupTablePageCount;
468
469 TRACE("MmInitPageLookupTable()\n");
470
471 // Mark every page as allocated initially
472 // We will go through and mark pages again according to the memory map
473 // But this will mark any holes not described in the map as allocated
474 MmMarkPagesInLookupTable(PageLookupTable, MmLowestPhysicalPage, TotalPageCount, LoaderFirmwarePermanent);
475
476 // Parse the whole memory map
477 while ((MemoryDescriptor = ArcGetMemoryDescriptor(MemoryDescriptor)) != NULL)
478 {
479 // Mark used pages in the lookup table
480
481 if (MemoryDescriptor->BasePage + MemoryDescriptor->PageCount <= TotalPageCount)
482 {
483 TRACE("Marking pages 0x%lx-0x%lx as type %s\n",
484 MemoryDescriptor->BasePage,
485 MemoryDescriptor->BasePage + MemoryDescriptor->PageCount,
486 MmGetSystemMemoryMapTypeString(MemoryDescriptor->MemoryType));
487 MmMarkPagesInLookupTable(PageLookupTable,
488 MemoryDescriptor->BasePage,
489 MemoryDescriptor->PageCount,
490 MemoryDescriptor->MemoryType);
491 }
492 else
493 TRACE("Ignoring pages 0x%lx-0x%lx (%s)\n",
494 MemoryDescriptor->BasePage,
495 MemoryDescriptor->BasePage + MemoryDescriptor->PageCount,
496 MmGetSystemMemoryMapTypeString(MemoryDescriptor->MemoryType));
497 }
498
499 // Mark the pages that the lookup table occupies as reserved
500 PageLookupTableStartPage = MmGetPageNumberFromAddress(PageLookupTable);
501 PageLookupTablePageCount = MmGetPageNumberFromAddress((PVOID)((ULONG_PTR)PageLookupTable + ROUND_UP(TotalPageCount * sizeof(PAGE_LOOKUP_TABLE_ITEM), MM_PAGE_SIZE))) - PageLookupTableStartPage;
502 TRACE("Marking the page lookup table pages as reserved StartPage: 0x%x PageCount: 0x%x\n", PageLookupTableStartPage, PageLookupTablePageCount);
503 MmMarkPagesInLookupTable(PageLookupTable, PageLookupTableStartPage, PageLookupTablePageCount, LoaderFirmwareTemporary);
504 }
505
MmMarkPagesInLookupTable(PVOID PageLookupTable,PFN_NUMBER StartPage,PFN_NUMBER PageCount,TYPE_OF_MEMORY PageAllocated)506 VOID MmMarkPagesInLookupTable(PVOID PageLookupTable, PFN_NUMBER StartPage, PFN_NUMBER PageCount, TYPE_OF_MEMORY PageAllocated)
507 {
508 PPAGE_LOOKUP_TABLE_ITEM RealPageLookupTable = (PPAGE_LOOKUP_TABLE_ITEM)PageLookupTable;
509 PFN_NUMBER Index;
510 TRACE("MmMarkPagesInLookupTable()\n");
511
512 /* Validate the range */
513 if ((StartPage < MmLowestPhysicalPage) ||
514 ((StartPage + PageCount - 1) > MmHighestPhysicalPage))
515 {
516 ERR("Memory (0x%lx:0x%lx) outside of lookup table! Valid range: 0x%lx-0x%lx.\n",
517 StartPage, PageCount, MmLowestPhysicalPage, MmHighestPhysicalPage);
518 return;
519 }
520
521 StartPage -= MmLowestPhysicalPage;
522 for (Index=StartPage; Index<(StartPage+PageCount); Index++)
523 {
524 #if 0
525 if ((Index <= (StartPage + 16)) || (Index >= (StartPage+PageCount-16)))
526 {
527 TRACE("Index = 0x%x StartPage = 0x%x PageCount = 0x%x\n", Index, StartPage, PageCount);
528 }
529 #endif
530 RealPageLookupTable[Index].PageAllocated = PageAllocated;
531 RealPageLookupTable[Index].PageAllocationLength = (PageAllocated != LoaderFree) ? 1 : 0;
532 }
533 TRACE("MmMarkPagesInLookupTable() Done\n");
534 }
535
MmAllocatePagesInLookupTable(PVOID PageLookupTable,PFN_NUMBER StartPage,PFN_NUMBER PageCount,TYPE_OF_MEMORY MemoryType)536 VOID MmAllocatePagesInLookupTable(PVOID PageLookupTable, PFN_NUMBER StartPage, PFN_NUMBER PageCount, TYPE_OF_MEMORY MemoryType)
537 {
538 PPAGE_LOOKUP_TABLE_ITEM RealPageLookupTable = (PPAGE_LOOKUP_TABLE_ITEM)PageLookupTable;
539 PFN_NUMBER Index;
540
541 StartPage -= MmLowestPhysicalPage;
542 for (Index=StartPage; Index<(StartPage+PageCount); Index++)
543 {
544 RealPageLookupTable[Index].PageAllocated = MemoryType;
545 RealPageLookupTable[Index].PageAllocationLength = (Index == StartPage) ? PageCount : 0;
546 }
547 }
548
MmCountFreePagesInLookupTable(PVOID PageLookupTable,PFN_NUMBER TotalPageCount)549 PFN_NUMBER MmCountFreePagesInLookupTable(PVOID PageLookupTable, PFN_NUMBER TotalPageCount)
550 {
551 PPAGE_LOOKUP_TABLE_ITEM RealPageLookupTable = (PPAGE_LOOKUP_TABLE_ITEM)PageLookupTable;
552 PFN_NUMBER Index;
553 PFN_NUMBER FreePageCount;
554
555 FreePageCount = 0;
556 for (Index=0; Index<TotalPageCount; Index++)
557 {
558 if (RealPageLookupTable[Index].PageAllocated == LoaderFree)
559 {
560 FreePageCount++;
561 }
562 }
563
564 return FreePageCount;
565 }
566
MmFindAvailablePages(PVOID PageLookupTable,PFN_NUMBER TotalPageCount,PFN_NUMBER PagesNeeded,BOOLEAN FromEnd)567 PFN_NUMBER MmFindAvailablePages(PVOID PageLookupTable, PFN_NUMBER TotalPageCount, PFN_NUMBER PagesNeeded, BOOLEAN FromEnd)
568 {
569 PPAGE_LOOKUP_TABLE_ITEM RealPageLookupTable = (PPAGE_LOOKUP_TABLE_ITEM)PageLookupTable;
570 PFN_NUMBER AvailablePagesSoFar;
571 PFN_NUMBER Index;
572
573 if (LastFreePageHint > TotalPageCount)
574 {
575 LastFreePageHint = TotalPageCount;
576 }
577
578 AvailablePagesSoFar = 0;
579 if (FromEnd)
580 {
581 /* Allocate "high" (from end) pages */
582 for (Index=LastFreePageHint-1; Index>0; Index--)
583 {
584 if (RealPageLookupTable[Index].PageAllocated != LoaderFree)
585 {
586 AvailablePagesSoFar = 0;
587 continue;
588 }
589 else
590 {
591 AvailablePagesSoFar++;
592 }
593
594 if (AvailablePagesSoFar >= PagesNeeded)
595 {
596 return Index + MmLowestPhysicalPage;
597 }
598 }
599 }
600 else
601 {
602 TRACE("Alloc low memory, LastFreePageHint 0x%x, TPC 0x%x\n", LastFreePageHint, TotalPageCount);
603 /* Allocate "low" pages */
604 for (Index=1; Index < LastFreePageHint; Index++)
605 {
606 if (RealPageLookupTable[Index].PageAllocated != LoaderFree)
607 {
608 AvailablePagesSoFar = 0;
609 continue;
610 }
611 else
612 {
613 AvailablePagesSoFar++;
614 }
615
616 if (AvailablePagesSoFar >= PagesNeeded)
617 {
618 return Index - AvailablePagesSoFar + 1 + MmLowestPhysicalPage;
619 }
620 }
621 }
622
623 return 0;
624 }
625
MmFindAvailablePagesBeforePage(PVOID PageLookupTable,PFN_NUMBER TotalPageCount,PFN_NUMBER PagesNeeded,PFN_NUMBER LastPage)626 PFN_NUMBER MmFindAvailablePagesBeforePage(PVOID PageLookupTable, PFN_NUMBER TotalPageCount, PFN_NUMBER PagesNeeded, PFN_NUMBER LastPage)
627 {
628 PPAGE_LOOKUP_TABLE_ITEM RealPageLookupTable = (PPAGE_LOOKUP_TABLE_ITEM)PageLookupTable;
629 PFN_NUMBER AvailablePagesSoFar;
630 PFN_NUMBER Index;
631
632 if (LastPage > TotalPageCount)
633 {
634 return MmFindAvailablePages(PageLookupTable, TotalPageCount, PagesNeeded, TRUE);
635 }
636
637 AvailablePagesSoFar = 0;
638 for (Index=LastPage-1; Index>0; Index--)
639 {
640 if (RealPageLookupTable[Index].PageAllocated != LoaderFree)
641 {
642 AvailablePagesSoFar = 0;
643 continue;
644 }
645 else
646 {
647 AvailablePagesSoFar++;
648 }
649
650 if (AvailablePagesSoFar >= PagesNeeded)
651 {
652 return Index + MmLowestPhysicalPage;
653 }
654 }
655
656 return 0;
657 }
658
MmUpdateLastFreePageHint(PVOID PageLookupTable,PFN_NUMBER TotalPageCount)659 VOID MmUpdateLastFreePageHint(PVOID PageLookupTable, PFN_NUMBER TotalPageCount)
660 {
661 PPAGE_LOOKUP_TABLE_ITEM RealPageLookupTable = (PPAGE_LOOKUP_TABLE_ITEM)PageLookupTable;
662 PFN_NUMBER Index;
663
664 for (Index=TotalPageCount-1; Index>0; Index--)
665 {
666 if (RealPageLookupTable[Index].PageAllocated == LoaderFree)
667 {
668 LastFreePageHint = Index + 1 + MmLowestPhysicalPage;
669 break;
670 }
671 }
672 }
673
MmAreMemoryPagesAvailable(PVOID PageLookupTable,PFN_NUMBER TotalPageCount,PVOID PageAddress,PFN_NUMBER PageCount)674 BOOLEAN MmAreMemoryPagesAvailable(PVOID PageLookupTable, PFN_NUMBER TotalPageCount, PVOID PageAddress, PFN_NUMBER PageCount)
675 {
676 PPAGE_LOOKUP_TABLE_ITEM RealPageLookupTable = (PPAGE_LOOKUP_TABLE_ITEM)PageLookupTable;
677 PFN_NUMBER StartPage;
678 PFN_NUMBER Index;
679
680 StartPage = MmGetPageNumberFromAddress(PageAddress);
681
682 if (StartPage < MmLowestPhysicalPage) return FALSE;
683
684 StartPage -= MmLowestPhysicalPage;
685
686 // Make sure they aren't trying to go past the
687 // end of available memory
688 if ((StartPage + PageCount) > TotalPageCount)
689 {
690 return FALSE;
691 }
692
693 for (Index = StartPage; Index < (StartPage + PageCount); Index++)
694 {
695 // If this page is allocated then there obviously isn't
696 // memory available so return FALSE
697 if (RealPageLookupTable[Index].PageAllocated != LoaderFree)
698 {
699 return FALSE;
700 }
701 }
702
703 return TRUE;
704 }
705