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Diffstat (limited to 'private/ntos/nbt/vxd/client.asm')
| -rw-r--r-- | private/ntos/nbt/vxd/client.asm | 427 |
1 files changed, 427 insertions, 0 deletions
diff --git a/private/ntos/nbt/vxd/client.asm b/private/ntos/nbt/vxd/client.asm new file mode 100644 index 000000000..0c44bbf79 --- /dev/null +++ b/private/ntos/nbt/vxd/client.asm @@ -0,0 +1,427 @@ + page ,132 + title client16.asm - 16-bit client support routines + + +;********************************************************************** +;** Microsoft Windows ** +;** Copyright(c) Microsoft Corp., 1993-1994 ** +;********************************************************************** +; +; +; client16.asm +; +; VXDLIB routines for dealing with 16-bit clients. +; +; The following functions are exported by this module: +; +; VxdMapSegmentOffsetToFlat +; +; +; FILE HISTORY: +; Koti 14-Jun-1994 Stole from KeithMo +; +; + +.386p +include vmm.inc +include shell.inc +include vwin32.inc +include netvxd.inc +include debug.inc + + +;;; +;;; Flag to _LinPage[Un]Lock. +;;; + +ifdef CHICAGO +VxdLinPageFlag equ PAGEMAPGLOBAL +else ; !CHICAGO +VxdLinPageFlag equ 0 +endif ; CHICAGO + + +;*** +;*** Locked code segment. +;*** + +VXD_LOCKED_CODE_SEG + +;;; +;;; Public functions. +;;; + +;******************************************************************* +; +; NAME: VxdMapSegmentOffsetToFlat +; +; SYNOPSIS: Maps a segment/offset pair to the corresponding flat +; pointer. +; +; ENTRY: VirtualHandle - VM handle. +; +; UserSegment - Segment value. +; +; UserOffset - Offset value +; +; RETURNS: LPVOID - The flat pointer, -1 if unsuccessful. +; +; NOTES: This routine was more-or-less stolen from the Map_Flat +; source in dos386\vmm\vmmutil.asm. +; +; HISTORY: +; KeithMo 27-Jan-1994 Created. +; +;******************************************************************** +BeginProc _VxdMapSegmentOffsetToFlat, PUBLIC, CCALL, ESP + +ArgVar VirtualHandle, DWORD +ArgVar UserSegment, DWORD +ArgVar UserOffset, DWORD + + EnterProc + SaveReg <ebx, ecx, edx, esi> + +;;; +;;; Capture the parameters. +;;; + + mov ebx, VirtualHandle ; (EBX) = VM handle + movzx eax, word ptr UserSegment ; (EAX) = segment + movzx esi, word ptr UserOffset ; (ESI) = offset + +;;; +;;; Short-circuit for NULL pointer. This is OK. +;;; + + or eax, eax + jz vmsotf_Exit + +;;; +;;; Determine if the current virtual machine is running in V86 +;;; mode or protected mode. +;;; + + test [ebx.CB_VM_Status], VMStat_PM_Exec + jz vmsotf_V86Mode + +;;; +;;; The target virtual machine is in protected mode. Map the +;;; selector to a flat pointer, then add the offset. +;;; + + VMMCall _SelectorMapFlat <ebx, eax, 0> + cmp eax, 0FFFFFFFFh + je vmsotf_Exit + + add eax, esi + +;;; +;;; If the pointer is within the first 1Meg+64K, add in the +;;; high-linear offset. +;;; + + cmp eax, 00110000h + jae short vmsotf_Exit + +vmsotf_AddHighLinear: + + add eax, [ebx.CB_High_Linear] + +;;; +;;; Cleanup stack & return. +;;; + +vmsotf_Exit: + + RestoreReg <esi, edx, ecx, ebx> + LeaveProc + Return + +;;; +;;; The target virtual machine is in V86 mode. Map the segment/offset +;;; pair to a linear address. +;;; + +vmsotf_V86Mode: + + shl eax, 4 + add eax, esi + jmp vmsotf_AddHighLinear + +EndProc _VxdMapSegmentOffsetToFlat + + +;******************************************************************* +; +; NAME: VxdLockBuffer +; +; SYNOPSIS: Locks a user-mode buffer so it may be safely accessed +; from ring 0. +; +; ENTRY: Buffer - Starting virtual address of user-mode buffer. +; +; BufferLength - Length (in BYTEs) of user-mode buffer. +; +; RETURN: LPVOID - Global locked address if successful, +; NULL if not. +; +; HISTORY: +; KeithMo 10-Nov-1993 Created. +; +;******************************************************************** +BeginProc _VxdLockBuffer, PUBLIC, CCALL, ESP + +ArgVar Buffer, DWORD +ArgVar BufferLength, DWORD + + EnterProc + SaveReg <ebx, edi, esi> + +;;; +;;; Grab parameters from stack. +;;; + + mov eax, Buffer ; User-mode buffer address. + mov ebx, BufferLength ; Buffer length. + +;;; +;;; Short-circuit for NULL buffer or zero length. +;;; + + or eax, eax + jz lub_Exit + or ebx, ebx + jz lub_Exit + +;;; +;;; Calculate the starting page number & number of pages to lock. +;;; + + movzx ecx, ax + and ch, 0Fh ; ecx = offset within first page. + mov esi, ecx ; save it for later + add ebx, ecx + add ebx, 0FFFh + shr ebx, 12 ; ebx = number of pages to lock. + shr eax, 12 ; eax = starting page number. + +;;; +;;; Ask VMM to lock the buffer. +;;; + + VMMCall _LinPageLock, <eax, ebx, VxdLinPageFlag> + or eax, eax + jz lub_Failure + +ifdef CHICAGO + add eax, esi ; add offset into first page. +else ; !CHICAGO + mov eax, Buffer ; retrieve original address. +endif ; CHICAGO + +;;; +;;; Common exit path. Cleanup stack & return. +;;; + +lub_Exit: + + RestoreReg <esi, edi, ebx> + LeaveProc + Return + +;;; +;;; LinPageLock failure. +;;; + +lub_Failure: + + Trace_Out "VxdLockBuffer: _LinPageLock failed" + xor eax, eax + jmp lub_Exit + +EndProc _VxdLockBuffer + + +;******************************************************************* +; +; NAME: VxdUnlockBuffer +; +; SYNOPSIS: Unlocks a user-mode buffer locked with LockUserBuffer. +; +; ENTRY: Buffer - Starting virtual address of user-mode buffer. +; +; BufferLength - Length (in BYTEs) of user-mode buffer. +; +; RETURN: DWORD - !0 if successful, 0 if not. +; +; HISTORY: +; KeithMo 10-Nov-1993 Created. +; +;******************************************************************** +BeginProc _VxdUnlockBuffer, PUBLIC, CCALL, ESP + +ArgVar Buffer, DWORD +ArgVar BufferLength, DWORD + + EnterProc + SaveReg <ebx, edi, esi> + +;;; +;;; Grab parameters from stack. +;;; + + mov eax, Buffer ; User-mode buffer address. + mov ebx, BufferLength ; Buffer length. + +;;; +;;; Short-circuit for NULL buffer or zero length. +;;; + + or eax, eax + jz uub_Success + or ebx, ebx + jz uub_Success + +;;; +;;; Calculate the starting page number & number of pages to unlock. +;;; + + movzx ecx, ax + and ch, 0Fh ; ecx = offset within first page. + add ebx, ecx + add ebx, 0FFFh + shr ebx, 12 ; ebx = number of pages to lock. + shr eax, 12 ; eax = starting page number. + +;;; +;;; Ask VMM to unlock the buffer. +;;; + + VMMCall _LinPageUnLock, <eax, ebx, VxdLinPageFlag> + or eax, eax + jz uub_Failure + +uub_Success: + + mov eax, 1 ; !0 == success + +;;; +;;; Common exit path. Cleanup stack & return. +;;; + +uub_Exit: + + RestoreReg <esi, edi, ebx> + LeaveProc + Return + +;;; +;;; LinPageUnLock failure. +;;; + +uub_Failure: + + Trace_Out "VxdUnlockBuffer: _LinPageUnlock failed" + xor eax, eax + jmp uub_Exit + +EndProc _VxdUnlockBuffer + + +; +; BUGBUG: VxdValidateBuffer is currently not used. Unifdef it if needed +; + + +;******************************************************************* +; +; NAME: VxdValidateBuffer +; +; SYNOPSIS: Validates that all pages within the given buffer are +; valid. +; +; ENTRY: Buffer - Starting virtual address of user-mode buffer. +; +; BufferLength - Length (in BYTEs) of user-mode buffer. +; +; RETURN: BOOL - TRUE if all pages in buffer are valid, FALSE +; otherwise. +; +; HISTORY: +; KeithMo 20-May-1994 Created. +; +;******************************************************************** +BeginProc _VxdValidateBuffer, PUBLIC, CCALL, ESP + +ArgVar Buffer, DWORD +ArgVar BufferLength, DWORD + + EnterProc + SaveReg <ebx, edi, esi> + +;;; +;;; Grab parameters from stack. +;;; + + mov eax, Buffer ; User-mode buffer address. + mov ebx, BufferLength ; Buffer length. + +;;; +;;; Short-circuit for NULL buffer or zero length. +;;; + + or eax, eax + jz vub_Success + or ebx, ebx + jz vub_Success + +;;; +;;; Calculate the starting page number & number of pages to validate. +;;; + + movzx ecx, ax + and ch, 0Fh ; ecx = offset within first page. + add ebx, ecx + add ebx, 0FFFh + shr ebx, 12 ; ebx = number of pages to check. + shr eax, 12 ; eax = starting page number. + mov ecx, ebx ; save page count + +;;; +;;; Ask VMM to validate the buffer. +;;; + + VMMCall _PageCheckLinRange, <eax, ebx, 0> + cmp eax, ecx + jne vub_Failure + +vub_Success: + + mov eax, 1 ; TRUE == success. + +;;; +;;; Common exit path. Cleanup stack & return. +;;; + +vub_Exit: + + RestoreReg <esi, edi, ebx> + LeaveProc + Return + +;;; +;;; _PageCheckLinRange failure. +;;; + +vub_Failure: + + xor eax, eax + jmp vub_Exit + +EndProc _VxdValidateBuffer + +VXD_LOCKED_CODE_ENDS + + +END |