v4.0/src/MEMM/EMM/EMMDISP.ASM

   1 page    58,132
   2 ;******************************************************************************
   3         title   EMMDISP - EMM dispatcher
   4 ;******************************************************************************
   5 ;
   6 ;   (C) Copyright MICROSOFT Corp. 1986
   7 ;
   8 ;   Title:      CEMM.EXE - COMPAQ Expanded Memory Manager 386 Driver
   9 ;               EMMLIB.LIB - Expanded Memory Manager Functions Library
  10 ;
  11 ;   Module:     EMM Dispatcher
  12 ;
  13 ;   Version:    0.04
  14 ;
  15 ;   Date:       May 17, 1986
  16 ;
  17 ;******************************************************************************
  18 ;
  19 ;   Change log:
  20 ;
  21 ;     DATE    REVISION                  DESCRIPTION
  22 ;   --------  --------  -------------------------------------------------------
  23 ;   5/17/86     0       initial code
  24 ;   6/14/86             modified registers on stack for exit and removed call
  25 ;                       to _emm_init (SBP).
  26 ;   6/28/86    0.02     Name change from CEMM386 to CEMM (SBP).
  27 ;   7/06/86    0.04     Changed data assumes to DGROUP (SBP).
  28 ;   5/25/88             Changed function range check to cover LIM 4.0 (PC)
  29 ;******************************************************************************
  30 ;
  31 ;   Functional Description:
  32 ;       This module serves to trap Int 67h, place
  33 ;       arguments on the stack and call the associated
  34 ;       function
  35 ;
  36 ;
  37 ;******************************************************************************
  38 .lfcond                                 ; list false conditionals
  39 .386p
  40
  41 ;******************************************************************************
  42 ;       P U B L I C S
  43 ;******************************************************************************
  44         public  int67_Entry
  45         public  dispatch_vector
  46
  47 ;******************************************************************************
  48 ;       I N C L U D E S
  49 ;******************************************************************************
  50         include vdmseg.inc
  51         include vdmsel.inc
  52         include emmdef.inc
  53 ;
  54 ;******************************************************************************
  55 ;       D E F I N E S
  56 ;******************************************************************************
  57 ;
  58 FALSE           equ     0
  59 TRUE            equ     not FALSE
  60 CR              equ     0dh
  61 LF              equ     0ah
  62
  63 mkvect  MACRO   name
  64         extrn   _&name:near
  65         dw      offset _TEXT:_&name
  66 endm
  67
  68 ;******************************************************************************
  69 ;       E X T E R N A L S
  70 ;******************************************************************************
  71
  72 _DATA   SEGMENT
  73 extrn   _EMMstatus:word
  74 extrn   Active_Status:byte
  75 extrn   Auto_Mode:byte
  76 extrn   _regp:word
  77 _DATA   ENDS
  78
  79
  80 ;******************************************************************************
  81 ;       local data
  82 ;******************************************************************************
  83 ;
  84 ; remove duplicated variables (defined in emmdata.asm)
  85 ;
  86 ;_DATA  SEGMENT
  87 ;
  88 ;_regp  label   word
  89 ;       dw      0
  90 ;       dw      0
  91 ;
  92 ;_DATA  ENDS
  93
  94 _TEXT   SEGMENT
  95 assume  cs:_text,ds:DGROUP,ss:DGROUP,es:DGROUP
  96 ;
  97         db      'PxB'
  98 ;
  99
 100 dispatch_vector label word
 101         mkvect  GetStatus
 102         mkvect  GetPageFrameAddress
 103         mkvect  GetUnallocatedPageCount
 104         mkvect  AllocatePages
 105         mkvect  MapHandlePage
 106         mkvect  DeallocatePages
 107         mkvect  GetEMMVersion
 108         mkvect  SavePageMap
 109         mkvect  RestorePageMap
 110         mkvect  GetPageMappingRegisterIOArray
 111         mkvect  GetLogicalToPhysicalPageTrans
 112         mkvect  GetEMMHandleCount
 113         mkvect  GetEMMHandlePages
 114         mkvect  GetAllEMMHandlePages
 115         mkvect  GetSetPageMap
 116         mkvect  GetSetPartial                   ; AH = 4Fh
 117                                                 ; 4.0 Functions...
 118         mkvect  MapHandleArray                  ; AH = 50h
 119         mkvect  ReallocatePages
 120         mkvect  GetSetHandleAttribute
 121         mkvect  GetSetHandleName
 122         mkvect  GetHandleDirectory
 123         mkvect  AlterMapAndJump
 124         mkvect  AlterMapAndCall
 125         mkvect  MoveExchangeMemory
 126         mkvect  GetMappablePAddrArray
 127         mkvect  GetInformation
 128         mkvect  AllocateRawPages
 129         mkvect  AlternateMapRegisterSet
 130         mkvect  PrepareForWarmBoot
 131         mkvect  OSDisable
 132
 133 ;*************************************
 134 ;       int67_Entry(PFlag,DS,ES) - entry point for int 67 (EMM functions)
 135 ;
 136 ;       unsigned        PFlag;  /* non-zero = protected mode, else */
 137 ;                               /*    virtual or real mode */
 138 ;       unsigned        DS;     /* DS segment value on entry to int67 */
 139 ;       unsigned        ES;     /* ES segment value on entry to int67 */
 140 ;
 141 ;       ENTRY:
 142 ;           REAL or VIRTUAL mode
 143 ;               DS = DGROUP segment
 144 ;           PROTECTED mode
 145 ;               DS = VDMD_GSEL
 146 ;
 147 ; At the point of the indirect call,
 148 ; The stack looks as follows:
 149 ;
 150 ;
 151 ;       +-------+
 152 ;       |  FS   |               +2CH    <--- entry FS segment
 153 ;       +-------+
 154 ;       |  GS   |               +2AH    <--- entry GS segment
 155 ;       +-------+
 156 ;       |  ES   |               +28H    <--- entry ES segment
 157 ;       +-------+
 158 ;       |  DS   |               +26h    <--- entry DS segment
 159 ;       +-------+
 160 ;       | PFlag |               +24h    <--- protected mode flag
 161 ;       +-------+
 162 ;       |  CS   |               +22h    <--- from FAR call to int67_handler
 163 ;       +-------+
 164 ;       |  ret  |               +20h    <--- CS:ret
 165 ;       +-------+
 166 ;       | EAX   |               +1C     <-+- from PUSH ALL
 167 ;       +-------+                         |
 168 ;       | ECX   |               +18       V
 169 ;       +-------+
 170 ;       | EDX   |               +14
 171 ;       +-------+
 172 ;       | EBX   |               +10
 173 ;       +-------+
 174 ;       | ESP   |               +C
 175 ;       +-------+
 176 ;       | EBP   |               +8
 177 ;       +-------+
 178 ;       | ESI   |               +4
 179 ;       +-------+
 180 ;       | EDI   |               <--- regp
 181 ;       +-------+
 182 ;
 183 ;*************************************
 184 int67_Entry     proc    far
 185         pushad                  ; save all regs
 186         mov     bp,sp           ;  SS:[BP] points to stack frame
 187 ;
 188         mov     [_regp],sp      ; regp points to regs on stack
 189         mov     [_regp+2],ss    ; regp now has a far ptr to regs
 190
 191         ;
 192         ; validate function code
 193         ;
 194         sub     ah,40h          ; check if entry code too small
 195         jb      i67_inv_exit    ; if so, error exit
 196         cmp     ah,(5Dh-40h)    ; check if entry code too big
 197         ja      i67_inv_exit    ; if so, error exit
 198
 199         ;
 200         ; check for VDM off
 201         ;
 202         cmp     [Auto_Mode],0           ;Q: Auto mode on ?
 203         jne     i67_jump                ;  Y: go ahead
 204         cmp     [Active_Status],0       ;  N:Q: are we ON ?
 205         je      i67_off_err             ;      N: exit with error code
 206
 207         ;
 208         ; call through the jump table
 209         ;
 210 i67_jump:
 211         xchg    ah,al           ; AL = function code
 212         mov     si,ax
 213         xchg    ah,al           ; AH = function code again
 214         and     si,00FFh        ; SI = function #
 215         shl     si,1            ; SI = table offset
 216         call    CS:dispatch_vector[si] ; call function
 217
 218 ok_exit:
 219         popad                   ; restore all regs
 220         ret                     ; bye!
 221
 222 i67_off_err:                            ; set h/w error
 223         mov     byte ptr [bp.rAX+1],EMM_HW_MALFUNCTION
 224         jmp     ok_exit
 225
 226 i67_inv_exit:                           ; set invalid function code error
 227         mov     byte ptr [bp.rAX+1],INVALID_FUNCTION
 228         jmp     ok_exit
 229
 230 int67_entry     endp
 231
 232 _TEXT   ENDS
 233 END
 234 \1a