| Message ID | 1471445945-19239-3-git-send-email-ard.biesheuvel@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
On Wed, Aug 17, 2016 at 04:59:03PM +0200, Ard Biesheuvel wrote: > The thunk generation is needlessly complex, given that it attempts to > deal with variable length instructions, which don't exist on AArch64. > > So replace it with a simple template coded in assembler, with a matching > struct definition in C. That way, we can create and manipulate the thunks > easily without looping over the instructions looking for 'magic' numbers. > > Also, use x16 rather than x9, since it is the architectural register to > use for thunks/veneers. > > Contributed-under: TianoCore Contribution Agreement 1.0 > Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org> > --- > MdeModulePkg/Universal/EbcDxe/AArch64/EbcLowLevel.S | 32 ++++- > MdeModulePkg/Universal/EbcDxe/AArch64/EbcSupport.c | 133 +++++--------------- > 2 files changed, 58 insertions(+), 107 deletions(-) > > diff --git a/MdeModulePkg/Universal/EbcDxe/AArch64/EbcLowLevel.S b/MdeModulePkg/Universal/EbcDxe/AArch64/EbcLowLevel.S > index a9678432d549..cb7a70b5a4f8 100644 > --- a/MdeModulePkg/Universal/EbcDxe/AArch64/EbcLowLevel.S > +++ b/MdeModulePkg/Universal/EbcDxe/AArch64/EbcLowLevel.S > @@ -3,8 +3,10 @@ > // This code provides low level routines that support the Virtual Machine > // for option ROMs. > // > -// Copyright (c) 2015, The Linux Foundation. All rights reserved. > +// Copyright (c) 2016, Linaro, Ltd. All rights reserved.<BR> > +// Copyright (c) 2015, The Linux Foundation. All rights reserved.<BR> > // Copyright (c) 2007 - 2014, Intel Corporation. All rights reserved.<BR> > +// > // This program and the accompanying materials > // are licensed and made available under the terms and conditions of the BSD License > // which accompanies this distribution. The full text of the license may be found at > @@ -19,6 +21,8 @@ ASM_GLOBAL ASM_PFX(EbcLLCALLEXNative) > ASM_GLOBAL ASM_PFX(EbcLLEbcInterpret) > ASM_GLOBAL ASM_PFX(EbcLLExecuteEbcImageEntryPoint) > > +ASM_GLOBAL ASM_PFX(mEbcInstructionBufferTemplate) > + > //**************************************************************************** > // EbcLLCALLEX > // > @@ -61,7 +65,7 @@ ASM_PFX(EbcLLCALLEXNative): > // > // This function is called by the thunk code to handle an Native to EBC call > // This can handle up to 16 arguments (1-8 on in x0-x7, 9-16 are on the stack) > -// x9 contains the Entry point that will be the first argument when > +// x16 contains the Entry point that will be the first argument when > // EBCInterpret is called. > // > //**************************************************************************** > @@ -97,7 +101,7 @@ ASM_PFX(EbcLLEbcInterpret): > mov x3, x2 > mov x2, x1 > mov x1, x0 > - mov x0, x9 > + mov x0, x16 > > // call C-code > bl ASM_PFX(EbcInterpret) > @@ -111,7 +115,7 @@ ASM_PFX(EbcLLEbcInterpret): > // EbcLLExecuteEbcImageEntryPoint > // > // This function is called by the thunk code to handle the image entry point > -// x9 contains the Entry point that will be the first argument when > +// x16 contains the Entry point that will be the third argument when > // ExecuteEbcImageEntryPoint is called. > // > //**************************************************************************** > @@ -120,9 +124,27 @@ ASM_PFX(EbcLLExecuteEbcImageEntryPoint): > // build new paramater calling convention > mov x2, x1 > mov x1, x0 > - mov x0, x9 > + mov x0, x16 > > // call C-code > bl ASM_PFX(ExecuteEbcImageEntryPoint) > ldp x29, x30, [sp], #16 > ret > + > +//**************************************************************************** > +// mEbcInstructionBufferTemplate > +//**************************************************************************** > + .section ".rodata", "a" > + .align 3 > +ASM_PFX(mEbcInstructionBufferTemplate): > + adr x17, 0f > + ldp x16, x17, [x17] > + br x17 > + > + // > + // Add a magic code here to help the VM recognize the thunk. > + // > + hlt #0xEBC > + > +0: .quad 0 // EBC_ENTRYPOINT_SIGNATURE > + .quad 0 // EBC_LL_EBC_ENTRYPOINT_SIGNATURE > diff --git a/MdeModulePkg/Universal/EbcDxe/AArch64/EbcSupport.c b/MdeModulePkg/Universal/EbcDxe/AArch64/EbcSupport.c > index 23261a070143..a5f21f400274 100644 > --- a/MdeModulePkg/Universal/EbcDxe/AArch64/EbcSupport.c > +++ b/MdeModulePkg/Universal/EbcDxe/AArch64/EbcSupport.c > @@ -2,8 +2,10 @@ > This module contains EBC support routines that are customized based on > the target AArch64 processor. > > -Copyright (c) 2015, The Linux Foundation. All rights reserved. > +Copyright (c) 2016, Linaro, Ltd. All rights reserved.<BR> > +Copyright (c) 2015, The Linux Foundation. All rights reserved.<BR> > Copyright (c) 2006 - 2014, Intel Corporation. All rights reserved.<BR> > + > This program and the accompanying materials > are licensed and made available under the terms and conditions of the BSD License > which accompanies this distribution. The full text of the license may be found at > @@ -22,47 +24,16 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. > // > #define STACK_REMAIN_SIZE (1024 * 4) > > -// > -// This is instruction buffer used to create EBC thunk > -// > -#define EBC_MAGIC_SIGNATURE 0xCA112EBCCA112EBCull > -#define EBC_ENTRYPOINT_SIGNATURE 0xAFAFAFAFAFAFAFAFull > -#define EBC_LL_EBC_ENTRYPOINT_SIGNATURE 0xFAFAFAFAFAFAFAFAull > -UINT8 mInstructionBufferTemplate[] = { > - 0x03, 0x00, 0x00, 0x14, //b pc+16 > - // > - // Add a magic code here to help the VM recognize the thunk.. > - // > - (UINT8)(EBC_MAGIC_SIGNATURE & 0xFF), > - (UINT8)((EBC_MAGIC_SIGNATURE >> 8) & 0xFF), > - (UINT8)((EBC_MAGIC_SIGNATURE >> 16) & 0xFF), > - (UINT8)((EBC_MAGIC_SIGNATURE >> 24) & 0xFF), > - (UINT8)((EBC_MAGIC_SIGNATURE >> 32) & 0xFF), > - (UINT8)((EBC_MAGIC_SIGNATURE >> 40) & 0xFF), > - (UINT8)((EBC_MAGIC_SIGNATURE >> 48) & 0xFF), > - (UINT8)((EBC_MAGIC_SIGNATURE >> 56) & 0xFF), > - 0x69, 0x00, 0x00, 0x58, //ldr x9, #32 > - 0x8A, 0x00, 0x00, 0x58, //ldr x10, #40 > - 0x05, 0x00, 0x00, 0x14, //b pc+32 > - (UINT8)(EBC_ENTRYPOINT_SIGNATURE & 0xFF), > - (UINT8)((EBC_ENTRYPOINT_SIGNATURE >> 8) & 0xFF), > - (UINT8)((EBC_ENTRYPOINT_SIGNATURE >> 16) & 0xFF), > - (UINT8)((EBC_ENTRYPOINT_SIGNATURE >> 24) & 0xFF), > - (UINT8)((EBC_ENTRYPOINT_SIGNATURE >> 32) & 0xFF), > - (UINT8)((EBC_ENTRYPOINT_SIGNATURE >> 40) & 0xFF), > - (UINT8)((EBC_ENTRYPOINT_SIGNATURE >> 48) & 0xFF), > - (UINT8)((EBC_ENTRYPOINT_SIGNATURE >> 56) & 0xFF), > - (UINT8)(EBC_LL_EBC_ENTRYPOINT_SIGNATURE & 0xFF), > - (UINT8)((EBC_LL_EBC_ENTRYPOINT_SIGNATURE >> 8) & 0xFF), > - (UINT8)((EBC_LL_EBC_ENTRYPOINT_SIGNATURE >> 16) & 0xFF), > - (UINT8)((EBC_LL_EBC_ENTRYPOINT_SIGNATURE >> 24) & 0xFF), > - (UINT8)((EBC_LL_EBC_ENTRYPOINT_SIGNATURE >> 32) & 0xFF), > - (UINT8)((EBC_LL_EBC_ENTRYPOINT_SIGNATURE >> 40) & 0xFF), > - (UINT8)((EBC_LL_EBC_ENTRYPOINT_SIGNATURE >> 48) & 0xFF), > - (UINT8)((EBC_LL_EBC_ENTRYPOINT_SIGNATURE >> 56) & 0xFF), > - 0x40, 0x01, 0x1F, 0xD6 //br x10 > - > -}; > +#pragma pack(1) > +typedef struct { > + UINT32 Instr[3]; > + UINT32 Magic; > + UINT64 EbcEntryPoint; > + UINT64 EbcLlEntryPoint; > +} EBC_INSTRUCTION_BUFFER; > +#pragma pack() > + > +extern CONST EBC_INSTRUCTION_BUFFER mEbcInstructionBufferTemplate; > > /** > Begin executing an EBC image. > @@ -414,10 +385,7 @@ EbcCreateThunks ( > IN UINT32 Flags > ) > { > - UINT8 *Ptr; > - UINT8 *ThunkBase; > - UINT32 Index; > - INT32 ThunkSize; > + EBC_INSTRUCTION_BUFFER *InstructionBuffer; > > // > // Check alignment of pointer to EBC code > @@ -426,51 +394,38 @@ EbcCreateThunks ( > return EFI_INVALID_PARAMETER; > } > > - ThunkSize = sizeof(mInstructionBufferTemplate); > - > - Ptr = AllocatePool (sizeof(mInstructionBufferTemplate)); > - > - if (Ptr == NULL) { > + InstructionBuffer = AllocatePool (sizeof (EBC_INSTRUCTION_BUFFER)); > + if (InstructionBuffer == NULL) { > return EFI_OUT_OF_RESOURCES; > } > - // > - // Print(L"Allocate TH: 0x%X\n", (UINT32)Ptr); > - // > - // Save the start address so we can add a pointer to it to a list later. > - // > - ThunkBase = Ptr; > > // > // Give them the address of our buffer we're going to fix up > // > - *Thunk = (VOID *) Ptr; > + *Thunk = InstructionBuffer; > > // > // Copy whole thunk instruction buffer template > // > - CopyMem (Ptr, mInstructionBufferTemplate, sizeof(mInstructionBufferTemplate)); > + CopyMem (InstructionBuffer, &mEbcInstructionBufferTemplate, > + sizeof (EBC_INSTRUCTION_BUFFER)); > > // > // Patch EbcEntryPoint and EbcLLEbcInterpret > // > - for (Index = 0; Index < sizeof(mInstructionBufferTemplate) - sizeof(UINTN); Index++) { > - if (*(UINTN *)&Ptr[Index] == EBC_ENTRYPOINT_SIGNATURE) { > - *(UINTN *)&Ptr[Index] = (UINTN)EbcEntryPoint; > - } > - if (*(UINTN *)&Ptr[Index] == EBC_LL_EBC_ENTRYPOINT_SIGNATURE) { > - if ((Flags & FLAG_THUNK_ENTRY_POINT) != 0) { > - *(UINTN *)&Ptr[Index] = (UINTN)EbcLLExecuteEbcImageEntryPoint; > - } else { > - *(UINTN *)&Ptr[Index] = (UINTN)EbcLLEbcInterpret; > - } > - } > + InstructionBuffer->EbcEntryPoint = (UINT64)EbcEntryPoint; > + if ((Flags & FLAG_THUNK_ENTRY_POINT) != 0) { > + InstructionBuffer->EbcLlEntryPoint = (UINT64)EbcLLExecuteEbcImageEntryPoint; > + } else { > + InstructionBuffer->EbcLlEntryPoint = (UINT64)EbcLLEbcInterpret; > } > > // > // Add the thunk to the list for this image. Do this last since the add > // function flushes the cache for us. > // > - EbcAddImageThunk (ImageHandle, (VOID *) ThunkBase, ThunkSize); > + EbcAddImageThunk (ImageHandle, InstructionBuffer, > + sizeof (EBC_INSTRUCTION_BUFFER)); > > return EFI_SUCCESS; > } > @@ -500,40 +455,15 @@ EbcLLCALLEX ( > IN UINT8 Size > ) > { > - UINTN IsThunk; > - UINTN TargetEbcAddr; > - UINT8 InstructionBuffer[sizeof(mInstructionBufferTemplate)]; > - UINTN Index; > - UINTN IndexOfEbcEntrypoint; > - > - IsThunk = 1; > - TargetEbcAddr = 0; > - IndexOfEbcEntrypoint = 0; > + CONST EBC_INSTRUCTION_BUFFER *InstructionBuffer; > > // > // Processor specific code to check whether the callee is a thunk to EBC. > // > - CopyMem (InstructionBuffer, (VOID *)FuncAddr, sizeof(InstructionBuffer)); > - // > - // Fill the signature according to mInstructionBufferTemplate > - // > - for (Index = 0; Index < sizeof(mInstructionBufferTemplate) - sizeof(UINTN); Index++) { > - if (*(UINTN *)&mInstructionBufferTemplate[Index] == EBC_ENTRYPOINT_SIGNATURE) { > - *(UINTN *)&InstructionBuffer[Index] = EBC_ENTRYPOINT_SIGNATURE; > - IndexOfEbcEntrypoint = Index; > - } > - if (*(UINTN *)&mInstructionBufferTemplate[Index] == EBC_LL_EBC_ENTRYPOINT_SIGNATURE) { > - *(UINTN *)&InstructionBuffer[Index] = EBC_LL_EBC_ENTRYPOINT_SIGNATURE; > - } > - } > - // > - // Check if we need thunk to native > - // > - if (CompareMem (InstructionBuffer, mInstructionBufferTemplate, sizeof(mInstructionBufferTemplate)) != 0) { > - IsThunk = 0; > - } > + InstructionBuffer = (EBC_INSTRUCTION_BUFFER *)FuncAddr; > > - if (IsThunk == 1){ > + if (CompareMem (InstructionBuffer, &mEbcInstructionBufferTemplate, > + sizeof(EBC_INSTRUCTION_BUFFER) - 2 * sizeof (UINT64)) == 0) { > // > // The callee is a thunk to EBC, adjust the stack pointer down 16 bytes and > // put our return address and frame pointer on the VM stack. > @@ -545,8 +475,7 @@ EbcLLCALLEX ( > VmPtr->Gpr[0] -= 8; > VmWriteMem64 (VmPtr, (UINTN) VmPtr->Gpr[0], (UINT64) (UINTN) (VmPtr->Ip + Size)); > > - CopyMem (&TargetEbcAddr, (UINT8 *)FuncAddr + IndexOfEbcEntrypoint, sizeof(UINTN)); > - VmPtr->Ip = (VMIP) (UINTN) TargetEbcAddr; > + VmPtr->Ip = (VMIP) InstructionBuffer->EbcEntryPoint; > } else { > // > // The callee is not a thunk to EBC, call native code, > -- > 2.7.4 > _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel
diff --git a/MdeModulePkg/Universal/EbcDxe/AArch64/EbcLowLevel.S b/MdeModulePkg/Universal/EbcDxe/AArch64/EbcLowLevel.S index a9678432d549..cb7a70b5a4f8 100644 --- a/MdeModulePkg/Universal/EbcDxe/AArch64/EbcLowLevel.S +++ b/MdeModulePkg/Universal/EbcDxe/AArch64/EbcLowLevel.S @@ -3,8 +3,10 @@ // This code provides low level routines that support the Virtual Machine // for option ROMs. // -// Copyright (c) 2015, The Linux Foundation. All rights reserved. +// Copyright (c) 2016, Linaro, Ltd. All rights reserved.<BR> +// Copyright (c) 2015, The Linux Foundation. All rights reserved.<BR> // Copyright (c) 2007 - 2014, Intel Corporation. All rights reserved.<BR> +// // This program and the accompanying materials // are licensed and made available under the terms and conditions of the BSD License // which accompanies this distribution. The full text of the license may be found at @@ -19,6 +21,8 @@ ASM_GLOBAL ASM_PFX(EbcLLCALLEXNative) ASM_GLOBAL ASM_PFX(EbcLLEbcInterpret) ASM_GLOBAL ASM_PFX(EbcLLExecuteEbcImageEntryPoint) +ASM_GLOBAL ASM_PFX(mEbcInstructionBufferTemplate) + //**************************************************************************** // EbcLLCALLEX // @@ -61,7 +65,7 @@ ASM_PFX(EbcLLCALLEXNative): // // This function is called by the thunk code to handle an Native to EBC call // This can handle up to 16 arguments (1-8 on in x0-x7, 9-16 are on the stack) -// x9 contains the Entry point that will be the first argument when +// x16 contains the Entry point that will be the first argument when // EBCInterpret is called. // //**************************************************************************** @@ -97,7 +101,7 @@ ASM_PFX(EbcLLEbcInterpret): mov x3, x2 mov x2, x1 mov x1, x0 - mov x0, x9 + mov x0, x16 // call C-code bl ASM_PFX(EbcInterpret) @@ -111,7 +115,7 @@ ASM_PFX(EbcLLEbcInterpret): // EbcLLExecuteEbcImageEntryPoint // // This function is called by the thunk code to handle the image entry point -// x9 contains the Entry point that will be the first argument when +// x16 contains the Entry point that will be the third argument when // ExecuteEbcImageEntryPoint is called. // //**************************************************************************** @@ -120,9 +124,27 @@ ASM_PFX(EbcLLExecuteEbcImageEntryPoint): // build new paramater calling convention mov x2, x1 mov x1, x0 - mov x0, x9 + mov x0, x16 // call C-code bl ASM_PFX(ExecuteEbcImageEntryPoint) ldp x29, x30, [sp], #16 ret + +//**************************************************************************** +// mEbcInstructionBufferTemplate +//**************************************************************************** + .section ".rodata", "a" + .align 3 +ASM_PFX(mEbcInstructionBufferTemplate): + adr x17, 0f + ldp x16, x17, [x17] + br x17 + + // + // Add a magic code here to help the VM recognize the thunk. + // + hlt #0xEBC + +0: .quad 0 // EBC_ENTRYPOINT_SIGNATURE + .quad 0 // EBC_LL_EBC_ENTRYPOINT_SIGNATURE diff --git a/MdeModulePkg/Universal/EbcDxe/AArch64/EbcSupport.c b/MdeModulePkg/Universal/EbcDxe/AArch64/EbcSupport.c index 23261a070143..a5f21f400274 100644 --- a/MdeModulePkg/Universal/EbcDxe/AArch64/EbcSupport.c +++ b/MdeModulePkg/Universal/EbcDxe/AArch64/EbcSupport.c @@ -2,8 +2,10 @@ This module contains EBC support routines that are customized based on the target AArch64 processor. -Copyright (c) 2015, The Linux Foundation. All rights reserved. +Copyright (c) 2016, Linaro, Ltd. All rights reserved.<BR> +Copyright (c) 2015, The Linux Foundation. All rights reserved.<BR> Copyright (c) 2006 - 2014, Intel Corporation. All rights reserved.<BR> + This program and the accompanying materials are licensed and made available under the terms and conditions of the BSD License which accompanies this distribution. The full text of the license may be found at @@ -22,47 +24,16 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. // #define STACK_REMAIN_SIZE (1024 * 4) -// -// This is instruction buffer used to create EBC thunk -// -#define EBC_MAGIC_SIGNATURE 0xCA112EBCCA112EBCull -#define EBC_ENTRYPOINT_SIGNATURE 0xAFAFAFAFAFAFAFAFull -#define EBC_LL_EBC_ENTRYPOINT_SIGNATURE 0xFAFAFAFAFAFAFAFAull -UINT8 mInstructionBufferTemplate[] = { - 0x03, 0x00, 0x00, 0x14, //b pc+16 - // - // Add a magic code here to help the VM recognize the thunk.. - // - (UINT8)(EBC_MAGIC_SIGNATURE & 0xFF), - (UINT8)((EBC_MAGIC_SIGNATURE >> 8) & 0xFF), - (UINT8)((EBC_MAGIC_SIGNATURE >> 16) & 0xFF), - (UINT8)((EBC_MAGIC_SIGNATURE >> 24) & 0xFF), - (UINT8)((EBC_MAGIC_SIGNATURE >> 32) & 0xFF), - (UINT8)((EBC_MAGIC_SIGNATURE >> 40) & 0xFF), - (UINT8)((EBC_MAGIC_SIGNATURE >> 48) & 0xFF), - (UINT8)((EBC_MAGIC_SIGNATURE >> 56) & 0xFF), - 0x69, 0x00, 0x00, 0x58, //ldr x9, #32 - 0x8A, 0x00, 0x00, 0x58, //ldr x10, #40 - 0x05, 0x00, 0x00, 0x14, //b pc+32 - (UINT8)(EBC_ENTRYPOINT_SIGNATURE & 0xFF), - (UINT8)((EBC_ENTRYPOINT_SIGNATURE >> 8) & 0xFF), - (UINT8)((EBC_ENTRYPOINT_SIGNATURE >> 16) & 0xFF), - (UINT8)((EBC_ENTRYPOINT_SIGNATURE >> 24) & 0xFF), - (UINT8)((EBC_ENTRYPOINT_SIGNATURE >> 32) & 0xFF), - (UINT8)((EBC_ENTRYPOINT_SIGNATURE >> 40) & 0xFF), - (UINT8)((EBC_ENTRYPOINT_SIGNATURE >> 48) & 0xFF), - (UINT8)((EBC_ENTRYPOINT_SIGNATURE >> 56) & 0xFF), - (UINT8)(EBC_LL_EBC_ENTRYPOINT_SIGNATURE & 0xFF), - (UINT8)((EBC_LL_EBC_ENTRYPOINT_SIGNATURE >> 8) & 0xFF), - (UINT8)((EBC_LL_EBC_ENTRYPOINT_SIGNATURE >> 16) & 0xFF), - (UINT8)((EBC_LL_EBC_ENTRYPOINT_SIGNATURE >> 24) & 0xFF), - (UINT8)((EBC_LL_EBC_ENTRYPOINT_SIGNATURE >> 32) & 0xFF), - (UINT8)((EBC_LL_EBC_ENTRYPOINT_SIGNATURE >> 40) & 0xFF), - (UINT8)((EBC_LL_EBC_ENTRYPOINT_SIGNATURE >> 48) & 0xFF), - (UINT8)((EBC_LL_EBC_ENTRYPOINT_SIGNATURE >> 56) & 0xFF), - 0x40, 0x01, 0x1F, 0xD6 //br x10 - -}; +#pragma pack(1) +typedef struct { + UINT32 Instr[3]; + UINT32 Magic; + UINT64 EbcEntryPoint; + UINT64 EbcLlEntryPoint; +} EBC_INSTRUCTION_BUFFER; +#pragma pack() + +extern CONST EBC_INSTRUCTION_BUFFER mEbcInstructionBufferTemplate; /** Begin executing an EBC image. @@ -414,10 +385,7 @@ EbcCreateThunks ( IN UINT32 Flags ) { - UINT8 *Ptr; - UINT8 *ThunkBase; - UINT32 Index; - INT32 ThunkSize; + EBC_INSTRUCTION_BUFFER *InstructionBuffer; // // Check alignment of pointer to EBC code @@ -426,51 +394,38 @@ EbcCreateThunks ( return EFI_INVALID_PARAMETER; } - ThunkSize = sizeof(mInstructionBufferTemplate); - - Ptr = AllocatePool (sizeof(mInstructionBufferTemplate)); - - if (Ptr == NULL) { + InstructionBuffer = AllocatePool (sizeof (EBC_INSTRUCTION_BUFFER)); + if (InstructionBuffer == NULL) { return EFI_OUT_OF_RESOURCES; } - // - // Print(L"Allocate TH: 0x%X\n", (UINT32)Ptr); - // - // Save the start address so we can add a pointer to it to a list later. - // - ThunkBase = Ptr; // // Give them the address of our buffer we're going to fix up // - *Thunk = (VOID *) Ptr; + *Thunk = InstructionBuffer; // // Copy whole thunk instruction buffer template // - CopyMem (Ptr, mInstructionBufferTemplate, sizeof(mInstructionBufferTemplate)); + CopyMem (InstructionBuffer, &mEbcInstructionBufferTemplate, + sizeof (EBC_INSTRUCTION_BUFFER)); // // Patch EbcEntryPoint and EbcLLEbcInterpret // - for (Index = 0; Index < sizeof(mInstructionBufferTemplate) - sizeof(UINTN); Index++) { - if (*(UINTN *)&Ptr[Index] == EBC_ENTRYPOINT_SIGNATURE) { - *(UINTN *)&Ptr[Index] = (UINTN)EbcEntryPoint; - } - if (*(UINTN *)&Ptr[Index] == EBC_LL_EBC_ENTRYPOINT_SIGNATURE) { - if ((Flags & FLAG_THUNK_ENTRY_POINT) != 0) { - *(UINTN *)&Ptr[Index] = (UINTN)EbcLLExecuteEbcImageEntryPoint; - } else { - *(UINTN *)&Ptr[Index] = (UINTN)EbcLLEbcInterpret; - } - } + InstructionBuffer->EbcEntryPoint = (UINT64)EbcEntryPoint; + if ((Flags & FLAG_THUNK_ENTRY_POINT) != 0) { + InstructionBuffer->EbcLlEntryPoint = (UINT64)EbcLLExecuteEbcImageEntryPoint; + } else { + InstructionBuffer->EbcLlEntryPoint = (UINT64)EbcLLEbcInterpret; } // // Add the thunk to the list for this image. Do this last since the add // function flushes the cache for us. // - EbcAddImageThunk (ImageHandle, (VOID *) ThunkBase, ThunkSize); + EbcAddImageThunk (ImageHandle, InstructionBuffer, + sizeof (EBC_INSTRUCTION_BUFFER)); return EFI_SUCCESS; } @@ -500,40 +455,15 @@ EbcLLCALLEX ( IN UINT8 Size ) { - UINTN IsThunk; - UINTN TargetEbcAddr; - UINT8 InstructionBuffer[sizeof(mInstructionBufferTemplate)]; - UINTN Index; - UINTN IndexOfEbcEntrypoint; - - IsThunk = 1; - TargetEbcAddr = 0; - IndexOfEbcEntrypoint = 0; + CONST EBC_INSTRUCTION_BUFFER *InstructionBuffer; // // Processor specific code to check whether the callee is a thunk to EBC. // - CopyMem (InstructionBuffer, (VOID *)FuncAddr, sizeof(InstructionBuffer)); - // - // Fill the signature according to mInstructionBufferTemplate - // - for (Index = 0; Index < sizeof(mInstructionBufferTemplate) - sizeof(UINTN); Index++) { - if (*(UINTN *)&mInstructionBufferTemplate[Index] == EBC_ENTRYPOINT_SIGNATURE) { - *(UINTN *)&InstructionBuffer[Index] = EBC_ENTRYPOINT_SIGNATURE; - IndexOfEbcEntrypoint = Index; - } - if (*(UINTN *)&mInstructionBufferTemplate[Index] == EBC_LL_EBC_ENTRYPOINT_SIGNATURE) { - *(UINTN *)&InstructionBuffer[Index] = EBC_LL_EBC_ENTRYPOINT_SIGNATURE; - } - } - // - // Check if we need thunk to native - // - if (CompareMem (InstructionBuffer, mInstructionBufferTemplate, sizeof(mInstructionBufferTemplate)) != 0) { - IsThunk = 0; - } + InstructionBuffer = (EBC_INSTRUCTION_BUFFER *)FuncAddr; - if (IsThunk == 1){ + if (CompareMem (InstructionBuffer, &mEbcInstructionBufferTemplate, + sizeof(EBC_INSTRUCTION_BUFFER) - 2 * sizeof (UINT64)) == 0) { // // The callee is a thunk to EBC, adjust the stack pointer down 16 bytes and // put our return address and frame pointer on the VM stack. @@ -545,8 +475,7 @@ EbcLLCALLEX ( VmPtr->Gpr[0] -= 8; VmWriteMem64 (VmPtr, (UINTN) VmPtr->Gpr[0], (UINT64) (UINTN) (VmPtr->Ip + Size)); - CopyMem (&TargetEbcAddr, (UINT8 *)FuncAddr + IndexOfEbcEntrypoint, sizeof(UINTN)); - VmPtr->Ip = (VMIP) (UINTN) TargetEbcAddr; + VmPtr->Ip = (VMIP) InstructionBuffer->EbcEntryPoint; } else { // // The callee is not a thunk to EBC, call native code,
The thunk generation is needlessly complex, given that it attempts to deal with variable length instructions, which don't exist on AArch64. So replace it with a simple template coded in assembler, with a matching struct definition in C. That way, we can create and manipulate the thunks easily without looping over the instructions looking for 'magic' numbers. Also, use x16 rather than x9, since it is the architectural register to use for thunks/veneers. Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> --- MdeModulePkg/Universal/EbcDxe/AArch64/EbcLowLevel.S | 32 ++++- MdeModulePkg/Universal/EbcDxe/AArch64/EbcSupport.c | 133 +++++--------------- 2 files changed, 58 insertions(+), 107 deletions(-) -- 2.7.4 _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel