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f3b33289 | 1 | /** @file\r |
2 | x64 Virtual Memory Management Services in the form of an IA-32 driver. \r | |
3 | Used to establish a 1:1 Virtual to Physical Mapping that is required to\r | |
4 | enter Long Mode (x64 64-bit mode).\r | |
5 | \r | |
6 | While we make a 1:1 mapping (identity mapping) for all physical pages \r | |
4140a663 | 7 | we still need to use the MTRR's to ensure that the cachability attributes\r |
f3b33289 | 8 | for all memory regions is correct.\r |
9 | \r | |
10 | The basic idea is to use 2MB page table entries where ever possible. If\r | |
11 | more granularity of cachability is required then 4K page tables are used.\r | |
12 | \r | |
13 | References:\r | |
4140a663 | 14 | 1) IA-32 Intel(R) Architecture Software Developer's Manual Volume 1:Basic Architecture, Intel\r |
15 | 2) IA-32 Intel(R) Architecture Software Developer's Manual Volume 2:Instruction Set Reference, Intel\r | |
16 | 3) IA-32 Intel(R) Architecture Software Developer's Manual Volume 3:System Programmer's Guide, Intel\r | |
f3b33289 | 17 | \r |
36829e67 | 18 | Copyright (c) 2006 - 2016, Intel Corporation. All rights reserved.<BR>\r |
5997daf7 LD |
19 | Copyright (c) 2017, AMD Incorporated. All rights reserved.<BR>\r |
20 | \r | |
cd5ebaa0 | 21 | This program and the accompanying materials\r |
f3b33289 | 22 | are licensed and made available under the terms and conditions of the BSD License\r |
23 | which accompanies this distribution. The full text of the license may be found at\r | |
24 | http://opensource.org/licenses/bsd-license.php\r | |
25 | \r | |
26 | THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r | |
27 | WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r | |
28 | \r | |
29 | **/ \r | |
30 | \r | |
31 | #include "DxeIpl.h"\r | |
32 | #include "VirtualMemory.h"\r | |
33 | \r | |
9189ec20 | 34 | /**\r |
382aeac2 | 35 | Clear legacy memory located at the first 4K-page, if available.\r |
9189ec20 | 36 | \r |
382aeac2 DB |
37 | This function traverses the whole HOB list to check if memory from 0 to 4095\r |
38 | exists and has not been allocated, and then clear it if so.\r | |
9189ec20 | 39 | \r |
382aeac2 | 40 | @param HobStart The start of HobList passed to DxeCore.\r |
9189ec20 JW |
41 | \r |
42 | **/\r | |
43 | VOID\r | |
44 | ClearFirst4KPage (\r | |
45 | IN VOID *HobStart\r | |
46 | )\r | |
47 | {\r | |
48 | EFI_PEI_HOB_POINTERS RscHob;\r | |
49 | EFI_PEI_HOB_POINTERS MemHob;\r | |
50 | BOOLEAN DoClear;\r | |
51 | \r | |
52 | RscHob.Raw = HobStart;\r | |
53 | MemHob.Raw = HobStart;\r | |
54 | DoClear = FALSE;\r | |
55 | \r | |
56 | //\r | |
57 | // Check if page 0 exists and free\r | |
58 | //\r | |
59 | while ((RscHob.Raw = GetNextHob (EFI_HOB_TYPE_RESOURCE_DESCRIPTOR,\r | |
60 | RscHob.Raw)) != NULL) {\r | |
61 | if (RscHob.ResourceDescriptor->ResourceType == EFI_RESOURCE_SYSTEM_MEMORY &&\r | |
62 | RscHob.ResourceDescriptor->PhysicalStart == 0) {\r | |
63 | DoClear = TRUE;\r | |
64 | //\r | |
65 | // Make sure memory at 0-4095 has not been allocated.\r | |
66 | //\r | |
67 | while ((MemHob.Raw = GetNextHob (EFI_HOB_TYPE_MEMORY_ALLOCATION,\r | |
68 | MemHob.Raw)) != NULL) {\r | |
69 | if (MemHob.MemoryAllocation->AllocDescriptor.MemoryBaseAddress\r | |
70 | < EFI_PAGE_SIZE) {\r | |
71 | DoClear = FALSE;\r | |
72 | break;\r | |
73 | }\r | |
74 | MemHob.Raw = GET_NEXT_HOB (MemHob);\r | |
75 | }\r | |
76 | break;\r | |
77 | }\r | |
78 | RscHob.Raw = GET_NEXT_HOB (RscHob);\r | |
79 | }\r | |
80 | \r | |
81 | if (DoClear) {\r | |
82 | DEBUG ((DEBUG_INFO, "Clearing first 4K-page!\r\n"));\r | |
83 | SetMem (NULL, EFI_PAGE_SIZE, 0);\r | |
84 | }\r | |
85 | \r | |
86 | return;\r | |
87 | }\r | |
88 | \r | |
382aeac2 DB |
89 | /**\r |
90 | Return configure status of NULL pointer detection feature.\r | |
91 | \r | |
92 | @return TRUE NULL pointer detection feature is enabled\r | |
93 | @return FALSE NULL pointer detection feature is disabled\r | |
94 | \r | |
95 | **/\r | |
9189ec20 JW |
96 | BOOLEAN\r |
97 | IsNullDetectionEnabled (\r | |
98 | VOID\r | |
99 | )\r | |
100 | {\r | |
101 | return ((PcdGet8 (PcdNullPointerDetectionPropertyMask) & BIT0) != 0);\r | |
102 | }\r | |
5997daf7 | 103 | \r |
5630cdfe SZ |
104 | /**\r |
105 | Enable Execute Disable Bit.\r | |
106 | \r | |
107 | **/\r | |
108 | VOID\r | |
109 | EnableExecuteDisableBit (\r | |
110 | VOID\r | |
111 | )\r | |
112 | {\r | |
113 | UINT64 MsrRegisters;\r | |
114 | \r | |
115 | MsrRegisters = AsmReadMsr64 (0xC0000080);\r | |
116 | MsrRegisters |= BIT11;\r | |
117 | AsmWriteMsr64 (0xC0000080, MsrRegisters);\r | |
118 | }\r | |
119 | \r | |
120 | /**\r | |
121 | Split 2M page to 4K.\r | |
122 | \r | |
123 | @param[in] PhysicalAddress Start physical address the 2M page covered.\r | |
124 | @param[in, out] PageEntry2M Pointer to 2M page entry.\r | |
125 | @param[in] StackBase Stack base address.\r | |
126 | @param[in] StackSize Stack size.\r | |
127 | \r | |
128 | **/\r | |
129 | VOID\r | |
130 | Split2MPageTo4K (\r | |
131 | IN EFI_PHYSICAL_ADDRESS PhysicalAddress,\r | |
132 | IN OUT UINT64 *PageEntry2M,\r | |
133 | IN EFI_PHYSICAL_ADDRESS StackBase,\r | |
134 | IN UINTN StackSize\r | |
135 | )\r | |
136 | {\r | |
137 | EFI_PHYSICAL_ADDRESS PhysicalAddress4K;\r | |
138 | UINTN IndexOfPageTableEntries;\r | |
139 | PAGE_TABLE_4K_ENTRY *PageTableEntry;\r | |
5997daf7 LD |
140 | UINT64 AddressEncMask;\r |
141 | \r | |
142 | //\r | |
143 | // Make sure AddressEncMask is contained to smallest supported address field\r | |
144 | //\r | |
145 | AddressEncMask = PcdGet64 (PcdPteMemoryEncryptionAddressOrMask) & PAGING_1G_ADDRESS_MASK_64;\r | |
5630cdfe SZ |
146 | \r |
147 | PageTableEntry = AllocatePages (1);\r | |
36829e67 | 148 | ASSERT (PageTableEntry != NULL);\r |
5997daf7 | 149 | \r |
5630cdfe SZ |
150 | //\r |
151 | // Fill in 2M page entry.\r | |
152 | //\r | |
5997daf7 | 153 | *PageEntry2M = (UINT64) (UINTN) PageTableEntry | AddressEncMask | IA32_PG_P | IA32_PG_RW;\r |
5630cdfe SZ |
154 | \r |
155 | PhysicalAddress4K = PhysicalAddress;\r | |
156 | for (IndexOfPageTableEntries = 0; IndexOfPageTableEntries < 512; IndexOfPageTableEntries++, PageTableEntry++, PhysicalAddress4K += SIZE_4KB) {\r | |
157 | //\r | |
158 | // Fill in the Page Table entries\r | |
159 | //\r | |
5997daf7 | 160 | PageTableEntry->Uint64 = (UINT64) PhysicalAddress4K | AddressEncMask;\r |
5630cdfe | 161 | PageTableEntry->Bits.ReadWrite = 1;\r |
9189ec20 JW |
162 | \r |
163 | if (IsNullDetectionEnabled () && PhysicalAddress4K == 0) {\r | |
164 | PageTableEntry->Bits.Present = 0;\r | |
165 | } else {\r | |
166 | PageTableEntry->Bits.Present = 1;\r | |
167 | }\r | |
168 | \r | |
169 | if (PcdGetBool (PcdSetNxForStack)\r | |
170 | && (PhysicalAddress4K >= StackBase)\r | |
171 | && (PhysicalAddress4K < StackBase + StackSize)) {\r | |
5630cdfe SZ |
172 | //\r |
173 | // Set Nx bit for stack.\r | |
174 | //\r | |
175 | PageTableEntry->Bits.Nx = 1;\r | |
176 | }\r | |
177 | }\r | |
178 | }\r | |
179 | \r | |
180 | /**\r | |
181 | Split 1G page to 2M.\r | |
182 | \r | |
183 | @param[in] PhysicalAddress Start physical address the 1G page covered.\r | |
184 | @param[in, out] PageEntry1G Pointer to 1G page entry.\r | |
185 | @param[in] StackBase Stack base address.\r | |
186 | @param[in] StackSize Stack size.\r | |
187 | \r | |
188 | **/\r | |
189 | VOID\r | |
190 | Split1GPageTo2M (\r | |
191 | IN EFI_PHYSICAL_ADDRESS PhysicalAddress,\r | |
192 | IN OUT UINT64 *PageEntry1G,\r | |
193 | IN EFI_PHYSICAL_ADDRESS StackBase,\r | |
194 | IN UINTN StackSize\r | |
195 | )\r | |
196 | {\r | |
197 | EFI_PHYSICAL_ADDRESS PhysicalAddress2M;\r | |
198 | UINTN IndexOfPageDirectoryEntries;\r | |
199 | PAGE_TABLE_ENTRY *PageDirectoryEntry;\r | |
5997daf7 LD |
200 | UINT64 AddressEncMask;\r |
201 | \r | |
202 | //\r | |
203 | // Make sure AddressEncMask is contained to smallest supported address field\r | |
204 | //\r | |
205 | AddressEncMask = PcdGet64 (PcdPteMemoryEncryptionAddressOrMask) & PAGING_1G_ADDRESS_MASK_64;\r | |
5630cdfe SZ |
206 | \r |
207 | PageDirectoryEntry = AllocatePages (1);\r | |
36829e67 | 208 | ASSERT (PageDirectoryEntry != NULL);\r |
5997daf7 | 209 | \r |
5630cdfe SZ |
210 | //\r |
211 | // Fill in 1G page entry.\r | |
212 | //\r | |
5997daf7 | 213 | *PageEntry1G = (UINT64) (UINTN) PageDirectoryEntry | AddressEncMask | IA32_PG_P | IA32_PG_RW;\r |
5630cdfe SZ |
214 | \r |
215 | PhysicalAddress2M = PhysicalAddress;\r | |
216 | for (IndexOfPageDirectoryEntries = 0; IndexOfPageDirectoryEntries < 512; IndexOfPageDirectoryEntries++, PageDirectoryEntry++, PhysicalAddress2M += SIZE_2MB) {\r | |
9189ec20 JW |
217 | if ((IsNullDetectionEnabled () && PhysicalAddress2M == 0)\r |
218 | || (PcdGetBool (PcdSetNxForStack)\r | |
219 | && (PhysicalAddress2M < StackBase + StackSize)\r | |
220 | && ((PhysicalAddress2M + SIZE_2MB) > StackBase))) {\r | |
5630cdfe | 221 | //\r |
9189ec20 | 222 | // Need to split this 2M page that covers NULL or stack range.\r |
5630cdfe SZ |
223 | //\r |
224 | Split2MPageTo4K (PhysicalAddress2M, (UINT64 *) PageDirectoryEntry, StackBase, StackSize);\r | |
225 | } else {\r | |
226 | //\r | |
227 | // Fill in the Page Directory entries\r | |
228 | //\r | |
5997daf7 | 229 | PageDirectoryEntry->Uint64 = (UINT64) PhysicalAddress2M | AddressEncMask;\r |
5630cdfe SZ |
230 | PageDirectoryEntry->Bits.ReadWrite = 1;\r |
231 | PageDirectoryEntry->Bits.Present = 1;\r | |
232 | PageDirectoryEntry->Bits.MustBe1 = 1;\r | |
233 | }\r | |
234 | }\r | |
235 | }\r | |
236 | \r | |
f3b33289 | 237 | /**\r |
238 | Allocates and fills in the Page Directory and Page Table Entries to\r | |
239 | establish a 1:1 Virtual to Physical mapping.\r | |
240 | \r | |
5630cdfe SZ |
241 | @param[in] StackBase Stack base address.\r |
242 | @param[in] StackSize Stack size.\r | |
f3b33289 | 243 | \r |
48557c65 | 244 | @return The address of 4 level page map.\r |
f3b33289 | 245 | \r |
246 | **/\r | |
247 | UINTN\r | |
248 | CreateIdentityMappingPageTables (\r | |
5630cdfe SZ |
249 | IN EFI_PHYSICAL_ADDRESS StackBase,\r |
250 | IN UINTN StackSize\r | |
f3b33289 | 251 | )\r |
252 | { \r | |
c56b6566 JY |
253 | UINT32 RegEax;\r |
254 | UINT32 RegEdx;\r | |
f3b33289 | 255 | UINT8 PhysicalAddressBits;\r |
256 | EFI_PHYSICAL_ADDRESS PageAddress;\r | |
257 | UINTN IndexOfPml4Entries;\r | |
258 | UINTN IndexOfPdpEntries;\r | |
259 | UINTN IndexOfPageDirectoryEntries;\r | |
4140a663 | 260 | UINT32 NumberOfPml4EntriesNeeded;\r |
261 | UINT32 NumberOfPdpEntriesNeeded;\r | |
f3b33289 | 262 | PAGE_MAP_AND_DIRECTORY_POINTER *PageMapLevel4Entry;\r |
263 | PAGE_MAP_AND_DIRECTORY_POINTER *PageMap;\r | |
264 | PAGE_MAP_AND_DIRECTORY_POINTER *PageDirectoryPointerEntry;\r | |
265 | PAGE_TABLE_ENTRY *PageDirectoryEntry;\r | |
266 | UINTN TotalPagesNum;\r | |
267 | UINTN BigPageAddress;\r | |
268 | VOID *Hob;\r | |
c56b6566 JY |
269 | BOOLEAN Page1GSupport;\r |
270 | PAGE_TABLE_1G_ENTRY *PageDirectory1GEntry;\r | |
5997daf7 LD |
271 | UINT64 AddressEncMask;\r |
272 | \r | |
273 | //\r | |
274 | // Make sure AddressEncMask is contained to smallest supported address field\r | |
275 | //\r | |
276 | AddressEncMask = PcdGet64 (PcdPteMemoryEncryptionAddressOrMask) & PAGING_1G_ADDRESS_MASK_64;\r | |
c56b6566 JY |
277 | \r |
278 | Page1GSupport = FALSE;\r | |
378175d2 JY |
279 | if (PcdGetBool(PcdUse1GPageTable)) {\r |
280 | AsmCpuid (0x80000000, &RegEax, NULL, NULL, NULL);\r | |
281 | if (RegEax >= 0x80000001) {\r | |
282 | AsmCpuid (0x80000001, NULL, NULL, NULL, &RegEdx);\r | |
283 | if ((RegEdx & BIT26) != 0) {\r | |
284 | Page1GSupport = TRUE;\r | |
285 | }\r | |
c56b6566 JY |
286 | }\r |
287 | }\r | |
f3b33289 | 288 | \r |
289 | //\r | |
c56b6566 | 290 | // Get physical address bits supported.\r |
f3b33289 | 291 | //\r |
f3b33289 | 292 | Hob = GetFirstHob (EFI_HOB_TYPE_CPU);\r |
293 | if (Hob != NULL) {\r | |
48557c65 | 294 | PhysicalAddressBits = ((EFI_HOB_CPU *) Hob)->SizeOfMemorySpace;\r |
c56b6566 JY |
295 | } else {\r |
296 | AsmCpuid (0x80000000, &RegEax, NULL, NULL, NULL);\r | |
297 | if (RegEax >= 0x80000008) {\r | |
298 | AsmCpuid (0x80000008, &RegEax, NULL, NULL, NULL);\r | |
299 | PhysicalAddressBits = (UINT8) RegEax;\r | |
300 | } else {\r | |
301 | PhysicalAddressBits = 36;\r | |
302 | }\r | |
f3b33289 | 303 | }\r |
304 | \r | |
4140a663 | 305 | //\r |
306 | // IA-32e paging translates 48-bit linear addresses to 52-bit physical addresses.\r | |
307 | //\r | |
308 | ASSERT (PhysicalAddressBits <= 52);\r | |
309 | if (PhysicalAddressBits > 48) {\r | |
310 | PhysicalAddressBits = 48;\r | |
311 | }\r | |
312 | \r | |
f3b33289 | 313 | //\r |
314 | // Calculate the table entries needed.\r | |
315 | //\r | |
316 | if (PhysicalAddressBits <= 39 ) {\r | |
317 | NumberOfPml4EntriesNeeded = 1;\r | |
c56b6566 | 318 | NumberOfPdpEntriesNeeded = (UINT32)LShiftU64 (1, (PhysicalAddressBits - 30));\r |
f3b33289 | 319 | } else {\r |
c56b6566 | 320 | NumberOfPml4EntriesNeeded = (UINT32)LShiftU64 (1, (PhysicalAddressBits - 39));\r |
f3b33289 | 321 | NumberOfPdpEntriesNeeded = 512;\r |
322 | }\r | |
323 | \r | |
324 | //\r | |
325 | // Pre-allocate big pages to avoid later allocations. \r | |
326 | //\r | |
c56b6566 JY |
327 | if (!Page1GSupport) {\r |
328 | TotalPagesNum = (NumberOfPdpEntriesNeeded + 1) * NumberOfPml4EntriesNeeded + 1;\r | |
329 | } else {\r | |
330 | TotalPagesNum = NumberOfPml4EntriesNeeded + 1;\r | |
331 | }\r | |
f3b33289 | 332 | BigPageAddress = (UINTN) AllocatePages (TotalPagesNum);\r |
333 | ASSERT (BigPageAddress != 0);\r | |
334 | \r | |
335 | //\r | |
336 | // By architecture only one PageMapLevel4 exists - so lets allocate storage for it.\r | |
337 | //\r | |
338 | PageMap = (VOID *) BigPageAddress;\r | |
c56b6566 | 339 | BigPageAddress += SIZE_4KB;\r |
f3b33289 | 340 | \r |
341 | PageMapLevel4Entry = PageMap;\r | |
342 | PageAddress = 0;\r | |
343 | for (IndexOfPml4Entries = 0; IndexOfPml4Entries < NumberOfPml4EntriesNeeded; IndexOfPml4Entries++, PageMapLevel4Entry++) {\r | |
344 | //\r | |
345 | // Each PML4 entry points to a page of Page Directory Pointer entires.\r | |
346 | // So lets allocate space for them and fill them in in the IndexOfPdpEntries loop.\r | |
347 | //\r | |
348 | PageDirectoryPointerEntry = (VOID *) BigPageAddress;\r | |
c56b6566 | 349 | BigPageAddress += SIZE_4KB;\r |
f3b33289 | 350 | \r |
351 | //\r | |
352 | // Make a PML4 Entry\r | |
353 | //\r | |
5997daf7 | 354 | PageMapLevel4Entry->Uint64 = (UINT64)(UINTN)PageDirectoryPointerEntry | AddressEncMask;\r |
f3b33289 | 355 | PageMapLevel4Entry->Bits.ReadWrite = 1;\r |
356 | PageMapLevel4Entry->Bits.Present = 1;\r | |
357 | \r | |
c56b6566 | 358 | if (Page1GSupport) {\r |
54d3b84e | 359 | PageDirectory1GEntry = (VOID *) PageDirectoryPointerEntry;\r |
c56b6566 JY |
360 | \r |
361 | for (IndexOfPageDirectoryEntries = 0; IndexOfPageDirectoryEntries < 512; IndexOfPageDirectoryEntries++, PageDirectory1GEntry++, PageAddress += SIZE_1GB) {\r | |
9189ec20 JW |
362 | if ((IsNullDetectionEnabled () && PageAddress == 0)\r |
363 | || (PcdGetBool (PcdSetNxForStack)\r | |
364 | && (PageAddress < StackBase + StackSize)\r | |
365 | && ((PageAddress + SIZE_1GB) > StackBase))) {\r | |
5630cdfe SZ |
366 | Split1GPageTo2M (PageAddress, (UINT64 *) PageDirectory1GEntry, StackBase, StackSize);\r |
367 | } else {\r | |
368 | //\r | |
369 | // Fill in the Page Directory entries\r | |
370 | //\r | |
5997daf7 | 371 | PageDirectory1GEntry->Uint64 = (UINT64)PageAddress | AddressEncMask;\r |
5630cdfe SZ |
372 | PageDirectory1GEntry->Bits.ReadWrite = 1;\r |
373 | PageDirectory1GEntry->Bits.Present = 1;\r | |
374 | PageDirectory1GEntry->Bits.MustBe1 = 1;\r | |
375 | }\r | |
c56b6566 JY |
376 | }\r |
377 | } else {\r | |
378 | for (IndexOfPdpEntries = 0; IndexOfPdpEntries < NumberOfPdpEntriesNeeded; IndexOfPdpEntries++, PageDirectoryPointerEntry++) {\r | |
379 | //\r | |
380 | // Each Directory Pointer entries points to a page of Page Directory entires.\r | |
381 | // So allocate space for them and fill them in in the IndexOfPageDirectoryEntries loop.\r | |
382 | // \r | |
383 | PageDirectoryEntry = (VOID *) BigPageAddress;\r | |
384 | BigPageAddress += SIZE_4KB;\r | |
385 | \r | |
386 | //\r | |
387 | // Fill in a Page Directory Pointer Entries\r | |
388 | //\r | |
5997daf7 | 389 | PageDirectoryPointerEntry->Uint64 = (UINT64)(UINTN)PageDirectoryEntry | AddressEncMask;\r |
c56b6566 JY |
390 | PageDirectoryPointerEntry->Bits.ReadWrite = 1;\r |
391 | PageDirectoryPointerEntry->Bits.Present = 1;\r | |
392 | \r | |
393 | for (IndexOfPageDirectoryEntries = 0; IndexOfPageDirectoryEntries < 512; IndexOfPageDirectoryEntries++, PageDirectoryEntry++, PageAddress += SIZE_2MB) {\r | |
9189ec20 JW |
394 | if ((IsNullDetectionEnabled () && PageAddress == 0)\r |
395 | || (PcdGetBool (PcdSetNxForStack)\r | |
396 | && (PageAddress < StackBase + StackSize)\r | |
397 | && ((PageAddress + SIZE_2MB) > StackBase))) {\r | |
5630cdfe | 398 | //\r |
9189ec20 | 399 | // Need to split this 2M page that covers NULL or stack range.\r |
5630cdfe SZ |
400 | //\r |
401 | Split2MPageTo4K (PageAddress, (UINT64 *) PageDirectoryEntry, StackBase, StackSize);\r | |
402 | } else {\r | |
403 | //\r | |
404 | // Fill in the Page Directory entries\r | |
405 | //\r | |
5997daf7 | 406 | PageDirectoryEntry->Uint64 = (UINT64)PageAddress | AddressEncMask;\r |
5630cdfe SZ |
407 | PageDirectoryEntry->Bits.ReadWrite = 1;\r |
408 | PageDirectoryEntry->Bits.Present = 1;\r | |
409 | PageDirectoryEntry->Bits.MustBe1 = 1;\r | |
410 | }\r | |
c56b6566 JY |
411 | }\r |
412 | }\r | |
f3b33289 | 413 | \r |
c56b6566 JY |
414 | for (; IndexOfPdpEntries < 512; IndexOfPdpEntries++, PageDirectoryPointerEntry++) {\r |
415 | ZeroMem (\r | |
416 | PageDirectoryPointerEntry,\r | |
417 | sizeof(PAGE_MAP_AND_DIRECTORY_POINTER)\r | |
418 | );\r | |
f3b33289 | 419 | }\r |
420 | }\r | |
421 | }\r | |
422 | \r | |
423 | //\r | |
424 | // For the PML4 entries we are not using fill in a null entry.\r | |
f3b33289 | 425 | //\r |
426 | for (; IndexOfPml4Entries < 512; IndexOfPml4Entries++, PageMapLevel4Entry++) {\r | |
c56b6566 JY |
427 | ZeroMem (\r |
428 | PageMapLevel4Entry,\r | |
429 | sizeof (PAGE_MAP_AND_DIRECTORY_POINTER)\r | |
430 | );\r | |
f3b33289 | 431 | }\r |
432 | \r | |
5630cdfe SZ |
433 | if (PcdGetBool (PcdSetNxForStack)) {\r |
434 | EnableExecuteDisableBit ();\r | |
435 | }\r | |
436 | \r | |
f3b33289 | 437 | return (UINTN)PageMap;\r |
438 | }\r | |
439 | \r |