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fb0b259e 1/** @file\r
53c71d09 2 This module contains EBC support routines that are customized based on\r
3 the target processor.\r
4\r
fa97cbf4 5Copyright (c) 2006 - 2011, Intel Corporation. All rights reserved.<BR>\r
e5eed7d3 6This program and the accompanying materials\r
fb0b259e 7are licensed and made available under the terms and conditions of the BSD License\r
8which accompanies this distribution. The full text of the license may be found at\r
9http://opensource.org/licenses/bsd-license.php\r
10\r
11THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
12WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
13\r
14**/\r
53c71d09 15\r
16#include "EbcInt.h"\r
17#include "EbcExecute.h"\r
18\r
19//\r
20// NOTE: This is the stack size allocated for the interpreter\r
21// when it executes an EBC image. The requirements can change\r
22// based on whether or not a debugger is present, and other\r
23// platform-specific configurations.\r
24//\r
25#define VM_STACK_SIZE (1024 * 4)\r
26#define EBC_THUNK_SIZE 32\r
27\r
28#define STACK_REMAIN_SIZE (1024 * 4)\r
53c71d09 29\r
7102b199
JY
30/**\r
31 Begin executing an EBC image.\r
32 This is used for Ebc Thunk call.\r
33\r
34 @return The value returned by the EBC application we're going to run.\r
35\r
36**/\r
37UINT64\r
38EFIAPI\r
39EbcLLEbcInterpret (\r
40 VOID\r
41 );\r
42\r
43/**\r
44 Begin executing an EBC image.\r
45 This is used for Ebc image entrypoint.\r
46\r
47 @return The value returned by the EBC application we're going to run.\r
48\r
49**/\r
50UINT64\r
51EFIAPI\r
52EbcLLExecuteEbcImageEntryPoint (\r
53 VOID\r
54 );\r
53c71d09 55\r
fb0b259e 56/**\r
57 This function is called to execute an EBC CALLEX instruction.\r
53c71d09 58 The function check the callee's content to see whether it is common native\r
59 code or a thunk to another piece of EBC code.\r
60 If the callee is common native code, use EbcLLCAllEXASM to manipulate,\r
61 otherwise, set the VM->IP to target EBC code directly to avoid another VM\r
62 be startup which cost time and stack space.\r
53c71d09 63\r
8e3bc754 64 @param VmPtr Pointer to a VM context.\r
65 @param FuncAddr Callee's address\r
66 @param NewStackPointer New stack pointer after the call\r
67 @param FramePtr New frame pointer after the call\r
68 @param Size The size of call instruction\r
53c71d09 69\r
fb0b259e 70**/\r
71VOID\r
72EbcLLCALLEX (\r
73 IN VM_CONTEXT *VmPtr,\r
74 IN UINTN FuncAddr,\r
75 IN UINTN NewStackPointer,\r
76 IN VOID *FramePtr,\r
77 IN UINT8 Size\r
78 )\r
53c71d09 79{\r
80 UINTN IsThunk;\r
81 UINTN TargetEbcAddr;\r
82\r
83 IsThunk = 1;\r
84 TargetEbcAddr = 0;\r
85\r
86 //\r
87 // Processor specific code to check whether the callee is a thunk to EBC.\r
88 //\r
89 if (*((UINT8 *)FuncAddr) != 0xB8) {\r
90 IsThunk = 0;\r
91 goto Action;\r
92 }\r
93 if (*((UINT8 *)FuncAddr + 1) != 0xBC) {\r
94 IsThunk = 0;\r
95 goto Action;\r
96 }\r
97 if (*((UINT8 *)FuncAddr + 2) != 0x2E) {\r
98 IsThunk = 0;\r
99 goto Action;\r
100 }\r
101 if (*((UINT8 *)FuncAddr + 3) != 0x11) {\r
102 IsThunk = 0;\r
103 goto Action;\r
104 }\r
105 if (*((UINT8 *)FuncAddr + 4) != 0xCA) {\r
106 IsThunk = 0;\r
107 goto Action;\r
108 }\r
109 if (*((UINT8 *)FuncAddr + 5) != 0xB8) {\r
110 IsThunk = 0;\r
111 goto Action;\r
112 }\r
113 if (*((UINT8 *)FuncAddr + 10) != 0xB9) {\r
114 IsThunk = 0;\r
115 goto Action;\r
116 }\r
117 if (*((UINT8 *)FuncAddr + 15) != 0xFF) {\r
118 IsThunk = 0;\r
119 goto Action;\r
120 }\r
121 if (*((UINT8 *)FuncAddr + 16) != 0xE1) {\r
122 IsThunk = 0;\r
123 goto Action;\r
124 }\r
125\r
126 TargetEbcAddr = ((UINTN)(*((UINT8 *)FuncAddr + 9)) << 24) + ((UINTN)(*((UINT8 *)FuncAddr + 8)) << 16) +\r
127 ((UINTN)(*((UINT8 *)FuncAddr + 7)) << 8) + ((UINTN)(*((UINT8 *)FuncAddr + 6)));\r
128\r
129Action:\r
130 if (IsThunk == 1){\r
131 //\r
132 // The callee is a thunk to EBC, adjust the stack pointer down 16 bytes and\r
133 // put our return address and frame pointer on the VM stack.\r
134 // Then set the VM's IP to new EBC code.\r
135 //\r
1ccdbf2a 136 VmPtr->Gpr[0] -= 8;\r
137 VmWriteMemN (VmPtr, (UINTN) VmPtr->Gpr[0], (UINTN) FramePtr);\r
138 VmPtr->FramePtr = (VOID *) (UINTN) VmPtr->Gpr[0];\r
139 VmPtr->Gpr[0] -= 8;\r
140 VmWriteMem64 (VmPtr, (UINTN) VmPtr->Gpr[0], (UINT64) (UINTN) (VmPtr->Ip + Size));\r
53c71d09 141\r
142 VmPtr->Ip = (VMIP) (UINTN) TargetEbcAddr;\r
143 } else {\r
144 //\r
fa97cbf4
JY
145 // The callee is not a thunk to EBC, call native code,\r
146 // and get return value\r
53c71d09 147 //\r
fa97cbf4 148 VmPtr->Gpr[7] = EbcLLCALLEXNative (FuncAddr, NewStackPointer, FramePtr);\r
fb0b259e 149\r
53c71d09 150 //\r
fa97cbf4 151 // Advance the IP.\r
53c71d09 152 //\r
53c71d09 153 VmPtr->Ip += Size;\r
154 }\r
155}\r
156\r
fb0b259e 157\r
158/**\r
7102b199 159 Begin executing an EBC image.\r
fb0b259e 160\r
8e3bc754 161 This is a thunk function. Microsoft x64 compiler only provide fast_call\r
162 calling convention, so the first four arguments are passed by rcx, rdx,\r
163 r8, and r9, while other arguments are passed in stack.\r
164\r
7102b199 165 @param EntryPoint The entrypoint of EBC code.\r
8e3bc754 166 @param Arg1 The 1st argument.\r
167 @param Arg2 The 2nd argument.\r
168 @param Arg3 The 3rd argument.\r
169 @param Arg4 The 4th argument.\r
170 @param Arg5 The 5th argument.\r
171 @param Arg6 The 6th argument.\r
172 @param Arg7 The 7th argument.\r
173 @param Arg8 The 8th argument.\r
174 @param Arg9 The 9th argument.\r
175 @param Arg10 The 10th argument.\r
176 @param Arg11 The 11th argument.\r
177 @param Arg12 The 12th argument.\r
178 @param Arg13 The 13th argument.\r
179 @param Arg14 The 14th argument.\r
180 @param Arg15 The 15th argument.\r
181 @param Arg16 The 16th argument.\r
fb0b259e 182\r
183 @return The value returned by the EBC application we're going to run.\r
184\r
185**/\r
53c71d09 186UINT64\r
fa97cbf4 187EFIAPI\r
53c71d09 188EbcInterpret (\r
7102b199
JY
189 IN UINTN EntryPoint,\r
190 IN UINTN Arg1,\r
191 IN UINTN Arg2,\r
192 IN UINTN Arg3,\r
193 IN UINTN Arg4,\r
194 IN UINTN Arg5,\r
195 IN UINTN Arg6,\r
196 IN UINTN Arg7,\r
197 IN UINTN Arg8,\r
198 IN UINTN Arg9,\r
199 IN UINTN Arg10,\r
200 IN UINTN Arg11,\r
201 IN UINTN Arg12,\r
202 IN UINTN Arg13,\r
203 IN UINTN Arg14,\r
204 IN UINTN Arg15,\r
205 IN UINTN Arg16\r
53c71d09 206 )\r
53c71d09 207{\r
208 //\r
209 // Create a new VM context on the stack\r
210 //\r
211 VM_CONTEXT VmContext;\r
212 UINTN Addr;\r
213 EFI_STATUS Status;\r
214 UINTN StackIndex;\r
215\r
216 //\r
7102b199 217 // Get the EBC entry point\r
53c71d09 218 //\r
7102b199 219 Addr = EntryPoint;\r
53c71d09 220\r
221 //\r
222 // Now clear out our context\r
223 //\r
224 ZeroMem ((VOID *) &VmContext, sizeof (VM_CONTEXT));\r
225\r
226 //\r
227 // Set the VM instruction pointer to the correct location in memory.\r
228 //\r
229 VmContext.Ip = (VMIP) Addr;\r
230 //\r
231 // Initialize the stack pointer for the EBC. Get the current system stack\r
232 // pointer and adjust it down by the max needed for the interpreter.\r
233 //\r
234\r
235 //\r
236 // Align the stack on a natural boundary\r
237 //\r
238\r
239 //\r
240 // Allocate stack pool\r
241 //\r
242 Status = GetEBCStack((EFI_HANDLE)-1, &VmContext.StackPool, &StackIndex);\r
243 if (EFI_ERROR(Status)) {\r
244 return Status;\r
245 }\r
246 VmContext.StackTop = (UINT8*)VmContext.StackPool + (STACK_REMAIN_SIZE);\r
1ccdbf2a 247 VmContext.Gpr[0] = (UINT64)(UINTN) ((UINT8*)VmContext.StackPool + STACK_POOL_SIZE);\r
248 VmContext.HighStackBottom = (UINTN)VmContext.Gpr[0];\r
249 VmContext.Gpr[0] &= ~(sizeof (UINTN) - 1);\r
250 VmContext.Gpr[0] -= sizeof (UINTN);\r
53c71d09 251\r
252 //\r
253 // Put a magic value in the stack gap, then adjust down again\r
254 //\r
1ccdbf2a 255 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) VM_STACK_KEY_VALUE;\r
256 VmContext.StackMagicPtr = (UINTN *) (UINTN) VmContext.Gpr[0];\r
257 VmContext.LowStackTop = (UINTN) VmContext.Gpr[0];\r
53c71d09 258\r
259 //\r
260 // For IA32, this is where we say our return address is\r
261 //\r
1ccdbf2a 262 VmContext.Gpr[0] -= sizeof (UINTN);\r
263 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg16;\r
264 VmContext.Gpr[0] -= sizeof (UINTN);\r
265 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg15;\r
266 VmContext.Gpr[0] -= sizeof (UINTN);\r
267 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg14;\r
268 VmContext.Gpr[0] -= sizeof (UINTN);\r
269 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg13;\r
270 VmContext.Gpr[0] -= sizeof (UINTN);\r
271 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg12;\r
272 VmContext.Gpr[0] -= sizeof (UINTN);\r
273 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg11;\r
274 VmContext.Gpr[0] -= sizeof (UINTN);\r
275 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg10;\r
276 VmContext.Gpr[0] -= sizeof (UINTN);\r
277 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg9;\r
278 VmContext.Gpr[0] -= sizeof (UINTN);\r
279 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg8;\r
280 VmContext.Gpr[0] -= sizeof (UINTN);\r
281 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg7;\r
282 VmContext.Gpr[0] -= sizeof (UINTN);\r
283 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg6;\r
284 VmContext.Gpr[0] -= sizeof (UINTN);\r
285 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg5;\r
286 VmContext.Gpr[0] -= sizeof (UINTN);\r
287 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg4;\r
288 VmContext.Gpr[0] -= sizeof (UINTN);\r
289 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg3;\r
290 VmContext.Gpr[0] -= sizeof (UINTN);\r
291 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg2;\r
292 VmContext.Gpr[0] -= sizeof (UINTN);\r
293 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg1;\r
294 VmContext.Gpr[0] -= 16;\r
295 VmContext.StackRetAddr = (UINT64) VmContext.Gpr[0];\r
53c71d09 296\r
297 //\r
298 // We need to keep track of where the EBC stack starts. This way, if the EBC\r
299 // accesses any stack variables above its initial stack setting, then we know\r
300 // it's accessing variables passed into it, which means the data is on the\r
301 // VM's stack.\r
302 // When we're called, on the stack (high to low) we have the parameters, the\r
303 // return address, then the saved ebp. Save the pointer to the return address.\r
304 // EBC code knows that's there, so should look above it for function parameters.\r
305 // The offset is the size of locals (VMContext + Addr + saved ebp).\r
306 // Note that the interpreter assumes there is a 16 bytes of return address on\r
307 // the stack too, so adjust accordingly.\r
308 // VmContext.HighStackBottom = (UINTN)(Addr + sizeof (VmContext) + sizeof (Addr));\r
309 //\r
310\r
311 //\r
312 // Begin executing the EBC code\r
313 //\r
314 EbcExecute (&VmContext);\r
315\r
316 //\r
317 // Return the value in R[7] unless there was an error\r
318 //\r
319 ReturnEBCStack(StackIndex);\r
1ccdbf2a 320 return (UINT64) VmContext.Gpr[7];\r
53c71d09 321}\r
322\r
53c71d09 323\r
fb0b259e 324/**\r
7102b199 325 Begin executing an EBC image.\r
53c71d09 326\r
7102b199 327 @param EntryPoint The entrypoint of EBC code.\r
8e3bc754 328 @param ImageHandle image handle for the EBC application we're executing\r
329 @param SystemTable standard system table passed into an driver's entry\r
330 point\r
53c71d09 331\r
fb0b259e 332 @return The value returned by the EBC application we're going to run.\r
53c71d09 333\r
fb0b259e 334**/\r
fb0b259e 335UINT64\r
fa97cbf4 336EFIAPI\r
fb0b259e 337ExecuteEbcImageEntryPoint (\r
7102b199 338 IN UINTN EntryPoint,\r
fb0b259e 339 IN EFI_HANDLE ImageHandle,\r
340 IN EFI_SYSTEM_TABLE *SystemTable\r
341 )\r
53c71d09 342{\r
343 //\r
344 // Create a new VM context on the stack\r
345 //\r
346 VM_CONTEXT VmContext;\r
347 UINTN Addr;\r
348 EFI_STATUS Status;\r
349 UINTN StackIndex;\r
350\r
351 //\r
7102b199 352 // Get the EBC entry point\r
53c71d09 353 //\r
7102b199 354 Addr = EntryPoint;\r
53c71d09 355\r
53c71d09 356 //\r
357 // Now clear out our context\r
358 //\r
359 ZeroMem ((VOID *) &VmContext, sizeof (VM_CONTEXT));\r
360\r
361 //\r
362 // Save the image handle so we can track the thunks created for this image\r
363 //\r
364 VmContext.ImageHandle = ImageHandle;\r
365 VmContext.SystemTable = SystemTable;\r
366\r
367 //\r
368 // Set the VM instruction pointer to the correct location in memory.\r
369 //\r
370 VmContext.Ip = (VMIP) Addr;\r
371\r
372 //\r
373 // Initialize the stack pointer for the EBC. Get the current system stack\r
374 // pointer and adjust it down by the max needed for the interpreter.\r
375 //\r
376\r
377 //\r
378 // Allocate stack pool\r
379 //\r
380 Status = GetEBCStack(ImageHandle, &VmContext.StackPool, &StackIndex);\r
381 if (EFI_ERROR(Status)) {\r
382 return Status;\r
383 }\r
384 VmContext.StackTop = (UINT8*)VmContext.StackPool + (STACK_REMAIN_SIZE);\r
1ccdbf2a 385 VmContext.Gpr[0] = (UINT64)(UINTN) ((UINT8*)VmContext.StackPool + STACK_POOL_SIZE);\r
386 VmContext.HighStackBottom = (UINTN)VmContext.Gpr[0];\r
387 VmContext.Gpr[0] -= sizeof (UINTN);\r
fb0b259e 388\r
53c71d09 389 //\r
390 // Put a magic value in the stack gap, then adjust down again\r
391 //\r
1ccdbf2a 392 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) VM_STACK_KEY_VALUE;\r
393 VmContext.StackMagicPtr = (UINTN *) (UINTN) VmContext.Gpr[0];\r
53c71d09 394\r
395 //\r
396 // Align the stack on a natural boundary\r
1ccdbf2a 397 // VmContext.Gpr[0] &= ~(sizeof(UINTN) - 1);\r
53c71d09 398 //\r
1ccdbf2a 399 VmContext.LowStackTop = (UINTN) VmContext.Gpr[0];\r
400 VmContext.Gpr[0] -= sizeof (UINTN);\r
401 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) SystemTable;\r
402 VmContext.Gpr[0] -= sizeof (UINTN);\r
403 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) ImageHandle;\r
53c71d09 404\r
1ccdbf2a 405 VmContext.Gpr[0] -= 16;\r
406 VmContext.StackRetAddr = (UINT64) VmContext.Gpr[0];\r
53c71d09 407 //\r
408 // VM pushes 16-bytes for return address. Simulate that here.\r
409 //\r
410\r
411 //\r
412 // Begin executing the EBC code\r
413 //\r
414 EbcExecute (&VmContext);\r
415\r
416 //\r
417 // Return the value in R[7] unless there was an error\r
418 //\r
fa97cbf4 419 ReturnEBCStack(StackIndex);\r
1ccdbf2a 420 return (UINT64) VmContext.Gpr[7];\r
53c71d09 421}\r
422\r
fb0b259e 423\r
424/**\r
8e3bc754 425 Create thunks for an EBC image entry point, or an EBC protocol service.\r
fb0b259e 426\r
8e3bc754 427 @param ImageHandle Image handle for the EBC image. If not null, then\r
428 we're creating a thunk for an image entry point.\r
429 @param EbcEntryPoint Address of the EBC code that the thunk is to call\r
430 @param Thunk Returned thunk we create here\r
431 @param Flags Flags indicating options for creating the thunk\r
fb0b259e 432\r
8e3bc754 433 @retval EFI_SUCCESS The thunk was created successfully.\r
434 @retval EFI_INVALID_PARAMETER The parameter of EbcEntryPoint is not 16-bit\r
435 aligned.\r
436 @retval EFI_OUT_OF_RESOURCES There is not enough memory to created the EBC\r
437 Thunk.\r
438 @retval EFI_BUFFER_TOO_SMALL EBC_THUNK_SIZE is not larger enough.\r
fb0b259e 439\r
440**/\r
53c71d09 441EFI_STATUS\r
442EbcCreateThunks (\r
443 IN EFI_HANDLE ImageHandle,\r
444 IN VOID *EbcEntryPoint,\r
445 OUT VOID **Thunk,\r
446 IN UINT32 Flags\r
447 )\r
53c71d09 448{\r
449 UINT8 *Ptr;\r
450 UINT8 *ThunkBase;\r
8e3bc754 451 UINT32 Index;\r
53c71d09 452 UINT32 Addr;\r
453 INT32 Size;\r
454 INT32 ThunkSize;\r
455\r
456 //\r
457 // Check alignment of pointer to EBC code\r
458 //\r
459 if ((UINT32) (UINTN) EbcEntryPoint & 0x01) {\r
460 return EFI_INVALID_PARAMETER;\r
461 }\r
462\r
463 Size = EBC_THUNK_SIZE;\r
464 ThunkSize = Size;\r
465\r
466 Ptr = AllocatePool (Size);\r
467\r
468 if (Ptr == NULL) {\r
469 return EFI_OUT_OF_RESOURCES;\r
470 }\r
471 //\r
472 // Print(L"Allocate TH: 0x%X\n", (UINT32)Ptr);\r
473 //\r
474 // Save the start address so we can add a pointer to it to a list later.\r
475 //\r
476 ThunkBase = Ptr;\r
477\r
478 //\r
479 // Give them the address of our buffer we're going to fix up\r
480 //\r
481 *Thunk = (VOID *) Ptr;\r
482\r
483 //\r
484 // Add a magic code here to help the VM recognize the thunk..\r
485 // mov eax, 0xca112ebc => B8 BC 2E 11 CA\r
486 //\r
487 *Ptr = 0xB8;\r
488 Ptr++;\r
489 Size--;\r
490 Addr = (UINT32) 0xCA112EBC;\r
8e3bc754 491 for (Index = 0; Index < sizeof (Addr); Index++) {\r
53c71d09 492 *Ptr = (UINT8) (UINTN) Addr;\r
493 Addr >>= 8;\r
494 Ptr++;\r
495 Size--;\r
496 }\r
497\r
498 //\r
499 // Add code bytes to load up a processor register with the EBC entry point.\r
500 // mov eax, 0xaa55aa55 => B8 55 AA 55 AA\r
501 // The first 8 bytes of the thunk entry is the address of the EBC\r
502 // entry point.\r
503 //\r
504 *Ptr = 0xB8;\r
505 Ptr++;\r
506 Size--;\r
507 Addr = (UINT32) EbcEntryPoint;\r
8e3bc754 508 for (Index = 0; Index < sizeof (Addr); Index++) {\r
53c71d09 509 *Ptr = (UINT8) (UINTN) Addr;\r
510 Addr >>= 8;\r
511 Ptr++;\r
512 Size--;\r
513 }\r
514 //\r
515 // Stick in a load of ecx with the address of appropriate VM function.\r
516 // mov ecx 12345678h => 0xB9 0x78 0x56 0x34 0x12\r
517 //\r
366219ab 518 if ((Flags & FLAG_THUNK_ENTRY_POINT) != 0) {\r
7102b199 519 Addr = (UINT32) (UINTN) EbcLLExecuteEbcImageEntryPoint;\r
53c71d09 520 } else {\r
7102b199 521 Addr = (UINT32) (UINTN) EbcLLEbcInterpret;\r
53c71d09 522 }\r
523\r
524 //\r
525 // MOV ecx\r
526 //\r
527 *Ptr = 0xB9;\r
528 Ptr++;\r
529 Size--;\r
8e3bc754 530 for (Index = 0; Index < sizeof (Addr); Index++) {\r
53c71d09 531 *Ptr = (UINT8) Addr;\r
532 Addr >>= 8;\r
533 Ptr++;\r
534 Size--;\r
535 }\r
536 //\r
537 // Stick in jump opcode bytes for jmp ecx => 0xFF 0xE1\r
538 //\r
539 *Ptr = 0xFF;\r
540 Ptr++;\r
541 Size--;\r
542 *Ptr = 0xE1;\r
543 Size--;\r
544\r
545 //\r
546 // Double check that our defined size is ok (application error)\r
547 //\r
548 if (Size < 0) {\r
549 ASSERT (FALSE);\r
550 return EFI_BUFFER_TOO_SMALL;\r
551 }\r
552 //\r
553 // Add the thunk to the list for this image. Do this last since the add\r
554 // function flushes the cache for us.\r
555 //\r
556 EbcAddImageThunk (ImageHandle, (VOID *) ThunkBase, ThunkSize);\r
557\r
558 return EFI_SUCCESS;\r
559}\r