2 This module contains EBC support routines that are customized based on
3 the target x64 processor.
5 Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>
6 SPDX-License-Identifier: BSD-2-Clause-Patent
11 #include "EbcExecute.h"
12 #include "EbcDebuggerHook.h"
15 // NOTE: This is the stack size allocated for the interpreter
16 // when it executes an EBC image. The requirements can change
17 // based on whether or not a debugger is present, and other
18 // platform-specific configurations.
20 #define VM_STACK_SIZE (1024 * 8)
22 #define STACK_REMAIN_SIZE (1024 * 4)
25 // This is instruction buffer used to create EBC thunk
27 #define EBC_ENTRYPOINT_SIGNATURE 0xAFAFAFAFAFAFAFAFull
28 #define EBC_LL_EBC_ENTRYPOINT_SIGNATURE 0xFAFAFAFAFAFAFAFAull
29 UINT8 mInstructionBufferTemplate
[] = {
31 // Add a magic code here to help the VM recognize the thunk..
32 // mov rax, 0xca112ebcca112ebc => 48 B8 BC 2E 11 CA BC 2E 11 CA
34 0x48, 0xB8, 0xBC, 0x2E, 0x11, 0xCA, 0xBC, 0x2E, 0x11, 0xCA,
36 // Add code bytes to load up a processor register with the EBC entry point.
37 // mov r10, EbcEntryPoint => 49 BA XX XX XX XX XX XX XX XX (To be fixed at runtime)
38 // These 8 bytes of the thunk entry is the address of the EBC
42 (UINT8
)(EBC_ENTRYPOINT_SIGNATURE
& 0xFF),
43 (UINT8
)((EBC_ENTRYPOINT_SIGNATURE
>> 8) & 0xFF),
44 (UINT8
)((EBC_ENTRYPOINT_SIGNATURE
>> 16) & 0xFF),
45 (UINT8
)((EBC_ENTRYPOINT_SIGNATURE
>> 24) & 0xFF),
46 (UINT8
)((EBC_ENTRYPOINT_SIGNATURE
>> 32) & 0xFF),
47 (UINT8
)((EBC_ENTRYPOINT_SIGNATURE
>> 40) & 0xFF),
48 (UINT8
)((EBC_ENTRYPOINT_SIGNATURE
>> 48) & 0xFF),
49 (UINT8
)((EBC_ENTRYPOINT_SIGNATURE
>> 56) & 0xFF),
51 // Stick in a load of r11 with the address of appropriate VM function.
52 // mov r11, EbcLLEbcInterpret => 49 BB XX XX XX XX XX XX XX XX (To be fixed at runtime)
55 (UINT8
)(EBC_LL_EBC_ENTRYPOINT_SIGNATURE
& 0xFF),
56 (UINT8
)((EBC_LL_EBC_ENTRYPOINT_SIGNATURE
>> 8) & 0xFF),
57 (UINT8
)((EBC_LL_EBC_ENTRYPOINT_SIGNATURE
>> 16) & 0xFF),
58 (UINT8
)((EBC_LL_EBC_ENTRYPOINT_SIGNATURE
>> 24) & 0xFF),
59 (UINT8
)((EBC_LL_EBC_ENTRYPOINT_SIGNATURE
>> 32) & 0xFF),
60 (UINT8
)((EBC_LL_EBC_ENTRYPOINT_SIGNATURE
>> 40) & 0xFF),
61 (UINT8
)((EBC_LL_EBC_ENTRYPOINT_SIGNATURE
>> 48) & 0xFF),
62 (UINT8
)((EBC_LL_EBC_ENTRYPOINT_SIGNATURE
>> 56) & 0xFF),
64 // Stick in jump opcode bytes
65 // jmp r11 => 41 FF E3
71 Begin executing an EBC image.
72 This is used for Ebc Thunk call.
74 @return The value returned by the EBC application we're going to run.
84 Begin executing an EBC image.
85 This is used for Ebc image entrypoint.
87 @return The value returned by the EBC application we're going to run.
92 EbcLLExecuteEbcImageEntryPoint (
97 Pushes a 64 bit unsigned value to the VM stack.
99 @param VmPtr The pointer to current VM context.
100 @param Arg The value to be pushed.
105 IN VM_CONTEXT
*VmPtr
,
110 // Advance the VM stack down, and then copy the argument to the stack.
111 // Hope it's aligned.
113 VmPtr
->Gpr
[0] -= sizeof (UINT64
);
114 *(UINT64
*) VmPtr
->Gpr
[0] = Arg
;
120 Begin executing an EBC image.
122 This is a thunk function. Microsoft x64 compiler only provide fast_call
123 calling convention, so the first four arguments are passed by rcx, rdx,
124 r8, and r9, while other arguments are passed in stack.
126 @param EntryPoint The entrypoint of EBC code.
127 @param Arg1 The 1st argument.
128 @param Arg2 The 2nd argument.
129 @param Arg3 The 3rd argument.
130 @param Arg4 The 4th argument.
131 @param Arg5 The 5th argument.
132 @param Arg6 The 6th argument.
133 @param Arg7 The 7th argument.
134 @param Arg8 The 8th argument.
135 @param Arg9 The 9th argument.
136 @param Arg10 The 10th argument.
137 @param Arg11 The 11th argument.
138 @param Arg12 The 12th argument.
139 @param Arg13 The 13th argument.
140 @param Arg14 The 14th argument.
141 @param Arg15 The 15th argument.
142 @param Arg16 The 16th argument.
144 @return The value returned by the EBC application we're going to run.
170 // Create a new VM context on the stack
172 VM_CONTEXT VmContext
;
178 // Get the EBC entry point
183 // Now clear out our context
185 ZeroMem ((VOID
*) &VmContext
, sizeof (VM_CONTEXT
));
188 // Set the VM instruction pointer to the correct location in memory.
190 VmContext
.Ip
= (VMIP
) Addr
;
193 // Initialize the stack pointer for the EBC. Get the current system stack
194 // pointer and adjust it down by the max needed for the interpreter.
198 // Adjust the VM's stack pointer down.
201 Status
= GetEBCStack((EFI_HANDLE
)(UINTN
)-1, &VmContext
.StackPool
, &StackIndex
);
202 if (EFI_ERROR(Status
)) {
205 VmContext
.StackTop
= (UINT8
*)VmContext
.StackPool
+ (STACK_REMAIN_SIZE
);
206 VmContext
.Gpr
[0] = (UINT64
) ((UINT8
*)VmContext
.StackPool
+ STACK_POOL_SIZE
);
207 VmContext
.HighStackBottom
= (UINTN
) VmContext
.Gpr
[0];
208 VmContext
.Gpr
[0] -= sizeof (UINTN
);
211 // Align the stack on a natural boundary.
213 VmContext
.Gpr
[0] &= ~(VM_REGISTER
)(sizeof (UINTN
) - 1);
216 // Put a magic value in the stack gap, then adjust down again.
218 *(UINTN
*) (UINTN
) (VmContext
.Gpr
[0]) = (UINTN
) VM_STACK_KEY_VALUE
;
219 VmContext
.StackMagicPtr
= (UINTN
*) (UINTN
) VmContext
.Gpr
[0];
222 // The stack upper to LowStackTop is belong to the VM.
224 VmContext
.LowStackTop
= (UINTN
) VmContext
.Gpr
[0];
227 // For the worst case, assume there are 4 arguments passed in registers, store
228 // them to VM's stack.
230 PushU64 (&VmContext
, (UINT64
) Arg16
);
231 PushU64 (&VmContext
, (UINT64
) Arg15
);
232 PushU64 (&VmContext
, (UINT64
) Arg14
);
233 PushU64 (&VmContext
, (UINT64
) Arg13
);
234 PushU64 (&VmContext
, (UINT64
) Arg12
);
235 PushU64 (&VmContext
, (UINT64
) Arg11
);
236 PushU64 (&VmContext
, (UINT64
) Arg10
);
237 PushU64 (&VmContext
, (UINT64
) Arg9
);
238 PushU64 (&VmContext
, (UINT64
) Arg8
);
239 PushU64 (&VmContext
, (UINT64
) Arg7
);
240 PushU64 (&VmContext
, (UINT64
) Arg6
);
241 PushU64 (&VmContext
, (UINT64
) Arg5
);
242 PushU64 (&VmContext
, (UINT64
) Arg4
);
243 PushU64 (&VmContext
, (UINT64
) Arg3
);
244 PushU64 (&VmContext
, (UINT64
) Arg2
);
245 PushU64 (&VmContext
, (UINT64
) Arg1
);
248 // Interpreter assumes 64-bit return address is pushed on the stack.
249 // The x64 does not do this so pad the stack accordingly.
251 PushU64 (&VmContext
, (UINT64
) 0);
252 PushU64 (&VmContext
, (UINT64
) 0x1234567887654321ULL
);
255 // For x64, this is where we say our return address is
257 VmContext
.StackRetAddr
= (UINT64
) VmContext
.Gpr
[0];
260 // We need to keep track of where the EBC stack starts. This way, if the EBC
261 // accesses any stack variables above its initial stack setting, then we know
262 // it's accessing variables passed into it, which means the data is on the
264 // When we're called, on the stack (high to low) we have the parameters, the
265 // return address, then the saved ebp. Save the pointer to the return address.
266 // EBC code knows that's there, so should look above it for function parameters.
267 // The offset is the size of locals (VMContext + Addr + saved ebp).
268 // Note that the interpreter assumes there is a 16 bytes of return address on
269 // the stack too, so adjust accordingly.
270 // VmContext.HighStackBottom = (UINTN)(Addr + sizeof (VmContext) + sizeof (Addr));
274 // Begin executing the EBC code
276 EbcDebuggerHookEbcInterpret (&VmContext
);
277 EbcExecute (&VmContext
);
280 // Return the value in Gpr[7] unless there was an error
282 ReturnEBCStack(StackIndex
);
283 return (UINT64
) VmContext
.Gpr
[7];
288 Begin executing an EBC image.
290 @param EntryPoint The entrypoint of EBC code.
291 @param ImageHandle image handle for the EBC application we're executing
292 @param SystemTable standard system table passed into an driver's entry
295 @return The value returned by the EBC application we're going to run.
300 ExecuteEbcImageEntryPoint (
302 IN EFI_HANDLE ImageHandle
,
303 IN EFI_SYSTEM_TABLE
*SystemTable
307 // Create a new VM context on the stack
309 VM_CONTEXT VmContext
;
315 // Get the EBC entry point
320 // Now clear out our context
322 ZeroMem ((VOID
*) &VmContext
, sizeof (VM_CONTEXT
));
325 // Save the image handle so we can track the thunks created for this image
327 VmContext
.ImageHandle
= ImageHandle
;
328 VmContext
.SystemTable
= SystemTable
;
331 // Set the VM instruction pointer to the correct location in memory.
333 VmContext
.Ip
= (VMIP
) Addr
;
336 // Initialize the stack pointer for the EBC. Get the current system stack
337 // pointer and adjust it down by the max needed for the interpreter.
340 Status
= GetEBCStack(ImageHandle
, &VmContext
.StackPool
, &StackIndex
);
341 if (EFI_ERROR(Status
)) {
344 VmContext
.StackTop
= (UINT8
*)VmContext
.StackPool
+ (STACK_REMAIN_SIZE
);
345 VmContext
.Gpr
[0] = (UINT64
) ((UINT8
*)VmContext
.StackPool
+ STACK_POOL_SIZE
);
346 VmContext
.HighStackBottom
= (UINTN
) VmContext
.Gpr
[0];
347 VmContext
.Gpr
[0] -= sizeof (UINTN
);
351 // Put a magic value in the stack gap, then adjust down again
353 *(UINTN
*) (UINTN
) (VmContext
.Gpr
[0]) = (UINTN
) VM_STACK_KEY_VALUE
;
354 VmContext
.StackMagicPtr
= (UINTN
*) (UINTN
) VmContext
.Gpr
[0];
357 // Align the stack on a natural boundary
358 VmContext
.Gpr
[0] &= ~(VM_REGISTER
)(sizeof(UINTN
) - 1);
360 VmContext
.LowStackTop
= (UINTN
) VmContext
.Gpr
[0];
363 // Simply copy the image handle and system table onto the EBC stack.
364 // Greatly simplifies things by not having to spill the args.
366 PushU64 (&VmContext
, (UINT64
) SystemTable
);
367 PushU64 (&VmContext
, (UINT64
) ImageHandle
);
370 // VM pushes 16-bytes for return address. Simulate that here.
372 PushU64 (&VmContext
, (UINT64
) 0);
373 PushU64 (&VmContext
, (UINT64
) 0x1234567887654321ULL
);
376 // For x64, this is where we say our return address is
378 VmContext
.StackRetAddr
= (UINT64
) VmContext
.Gpr
[0];
381 // Entry function needn't access high stack context, simply
382 // put the stack pointer here.
386 // Begin executing the EBC code
388 EbcDebuggerHookExecuteEbcImageEntryPoint (&VmContext
);
389 EbcExecute (&VmContext
);
392 // Return the value in Gpr[7] unless there was an error
394 ReturnEBCStack(StackIndex
);
395 return (UINT64
) VmContext
.Gpr
[7];
400 Create thunks for an EBC image entry point, or an EBC protocol service.
402 @param ImageHandle Image handle for the EBC image. If not null, then
403 we're creating a thunk for an image entry point.
404 @param EbcEntryPoint Address of the EBC code that the thunk is to call
405 @param Thunk Returned thunk we create here
406 @param Flags Flags indicating options for creating the thunk
408 @retval EFI_SUCCESS The thunk was created successfully.
409 @retval EFI_INVALID_PARAMETER The parameter of EbcEntryPoint is not 16-bit
411 @retval EFI_OUT_OF_RESOURCES There is not enough memory to created the EBC
413 @retval EFI_BUFFER_TOO_SMALL EBC_THUNK_SIZE is not larger enough.
418 IN EFI_HANDLE ImageHandle
,
419 IN VOID
*EbcEntryPoint
,
430 // Check alignment of pointer to EBC code
432 if ((UINT32
) (UINTN
) EbcEntryPoint
& 0x01) {
433 return EFI_INVALID_PARAMETER
;
436 ThunkSize
= sizeof(mInstructionBufferTemplate
);
438 Ptr
= EbcAllocatePoolForThunk (sizeof(mInstructionBufferTemplate
));
441 return EFI_OUT_OF_RESOURCES
;
444 // Print(L"Allocate TH: 0x%X\n", (UINT32)Ptr);
446 // Save the start address so we can add a pointer to it to a list later.
451 // Give them the address of our buffer we're going to fix up
453 *Thunk
= (VOID
*) Ptr
;
456 // Copy whole thunk instruction buffer template
458 CopyMem (Ptr
, mInstructionBufferTemplate
, sizeof(mInstructionBufferTemplate
));
461 // Patch EbcEntryPoint and EbcLLEbcInterpret
463 for (Index
= 0; Index
< sizeof(mInstructionBufferTemplate
) - sizeof(UINTN
); Index
++) {
464 if (*(UINTN
*)&Ptr
[Index
] == EBC_ENTRYPOINT_SIGNATURE
) {
465 *(UINTN
*)&Ptr
[Index
] = (UINTN
)EbcEntryPoint
;
467 if (*(UINTN
*)&Ptr
[Index
] == EBC_LL_EBC_ENTRYPOINT_SIGNATURE
) {
468 if ((Flags
& FLAG_THUNK_ENTRY_POINT
) != 0) {
469 *(UINTN
*)&Ptr
[Index
] = (UINTN
)EbcLLExecuteEbcImageEntryPoint
;
471 *(UINTN
*)&Ptr
[Index
] = (UINTN
)EbcLLEbcInterpret
;
477 // Add the thunk to the list for this image. Do this last since the add
478 // function flushes the cache for us.
480 EbcAddImageThunk (ImageHandle
, (VOID
*) ThunkBase
, ThunkSize
);
487 This function is called to execute an EBC CALLEX instruction.
488 The function check the callee's content to see whether it is common native
489 code or a thunk to another piece of EBC code.
490 If the callee is common native code, use EbcLLCAllEXASM to manipulate,
491 otherwise, set the VM->IP to target EBC code directly to avoid another VM
492 be startup which cost time and stack space.
494 @param VmPtr Pointer to a VM context.
495 @param FuncAddr Callee's address
496 @param NewStackPointer New stack pointer after the call
497 @param FramePtr New frame pointer after the call
498 @param Size The size of call instruction
503 IN VM_CONTEXT
*VmPtr
,
505 IN UINTN NewStackPointer
,
512 UINT8 InstructionBuffer
[sizeof(mInstructionBufferTemplate
)];
514 UINTN IndexOfEbcEntrypoint
;
518 IndexOfEbcEntrypoint
= 0;
521 // Processor specific code to check whether the callee is a thunk to EBC.
523 CopyMem (InstructionBuffer
, (VOID
*)FuncAddr
, sizeof(InstructionBuffer
));
525 // Fill the signature according to mInstructionBufferTemplate
527 for (Index
= 0; Index
< sizeof(mInstructionBufferTemplate
) - sizeof(UINTN
); Index
++) {
528 if (*(UINTN
*)&mInstructionBufferTemplate
[Index
] == EBC_ENTRYPOINT_SIGNATURE
) {
529 *(UINTN
*)&InstructionBuffer
[Index
] = EBC_ENTRYPOINT_SIGNATURE
;
530 IndexOfEbcEntrypoint
= Index
;
532 if (*(UINTN
*)&mInstructionBufferTemplate
[Index
] == EBC_LL_EBC_ENTRYPOINT_SIGNATURE
) {
533 *(UINTN
*)&InstructionBuffer
[Index
] = EBC_LL_EBC_ENTRYPOINT_SIGNATURE
;
537 // Check if we need thunk to native
539 if (CompareMem (InstructionBuffer
, mInstructionBufferTemplate
, sizeof(mInstructionBufferTemplate
)) != 0) {
545 // The callee is a thunk to EBC, adjust the stack pointer down 16 bytes and
546 // put our return address and frame pointer on the VM stack.
547 // Then set the VM's IP to new EBC code.
550 VmWriteMemN (VmPtr
, (UINTN
) VmPtr
->Gpr
[0], (UINTN
) FramePtr
);
551 VmPtr
->FramePtr
= (VOID
*) (UINTN
) VmPtr
->Gpr
[0];
553 VmWriteMem64 (VmPtr
, (UINTN
) VmPtr
->Gpr
[0], (UINT64
) (UINTN
) (VmPtr
->Ip
+ Size
));
555 CopyMem (&TargetEbcAddr
, (UINT8
*)FuncAddr
+ IndexOfEbcEntrypoint
, sizeof(UINTN
));
556 VmPtr
->Ip
= (VMIP
) (UINTN
) TargetEbcAddr
;
559 // The callee is not a thunk to EBC, call native code,
560 // and get return value.
562 VmPtr
->Gpr
[7] = EbcLLCALLEXNative (FuncAddr
, NewStackPointer
, FramePtr
);