v4.0/src/DEV/SMARTDRV/AB_MACRO.ASM

   1 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
   2 ;
   3 ;       MACRO definitions for expanded memory manager
   4 ;
   5 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
   6 ;
   7 ;       1. MACRO to save mapping context in case somebody else has
   8 ;          mapped the page registers.
   9 ;
  10 save_mapping_context    macro
  11 local   save_agn_m,save_err_m,save_ok_m,save_exit_m
  12 ;
  13 ;       the save mapping call for the above board -->
  14 ;
  15 ;               mov     ah,47h
  16 ;               mov     dx,handle
  17 ;               int     67h
  18 ;
  19 ;       on return ax = 0 signifies success
  20 ;
  21 ;
  22         push    ax              ; save registers
  23         push    dx
  24 ;
  25 ;       set up emm registers and execute call to save mapping context
  26 ;
  27 save_agn_m:
  28         mov     dx,cs:[above_pid]               ; get emm handle
  29         mov     ah,above_save_map_pid   ; save map call
  30         int     67h                     ; call the manager
  31         or      ah,ah                   ; is there an error?
  32         jz      save_ok_m                       ; if not we are done
  33 ;
  34 ;       error in saving mapping context, check for error
  35 ;
  36         cmp     ah,above_error_busy     ; if the emm manager was busy
  37         jz      save_agn_m              ; we would like to try again
  38 ;
  39 ;       unrecoverable error, indicate error type in al
  40 ;
  41         pop     dx
  42         pop     dx                      ; pop the regs off the stack
  43 ;
  44         mov     al,0aah                 ; drive not ready
  45         cmp     ah,above_error_cntxt_no_stack   ;
  46         jz      save_err_m
  47         cmp     ah,above_error_second_save      ;
  48         ja      save_err_m
  49         mov     al,0bbh                 ; general failure
  50 save_err_m:
  51         stc
  52         jmp     short save_exit_m
  53 save_ok_m:
  54         clc
  55         pop     dx
  56         pop     ax                      ; restore registers
  57 save_exit_m:
  58         endm
  59 ;
  60 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
  61 ;
  62 ;       2. MACRO to restore the mapping context saved earlier
  63 ;
  64 restore_mapping_context macro
  65 local   rest_agn_m, rest_ok_m, rest_exit_m
  66 ;
  67 ;       the restore above map call -->
  68 ;
  69 ;               mov     ah,48h
  70 ;               mov     dx,handle
  71 ;               int     67h
  72 ;       ah = 0 is success
  73 ;
  74 ;
  75         push    ax
  76         pushf
  77 ;
  78 rest_agn_m:
  79         mov     dx,cs:[above_pid]       ; get emm handle
  80         mov     ah,above_restore_map_pid ; restore map call
  81         int     67h                     ; call manager
  82         or      ah,ah                   ; is there any error
  83         jz      rest_ok_m                       ; if not go to finish up
  84 ;
  85 ;       error condition, check for recoverable error
  86 ;
  87         cmp     ah,above_error_busy     ; if manager was busy
  88         jz      rest_agn_m              ; we sure can try again
  89         cmp     ah,above_error_no_cntxt ;
  90         jz      rest_ok_m                       ; ignore invalid pid error
  91 ;
  92 ;       unrecoverable error
  93 ;
  94         pop     dx
  95         pop     dx
  96         mov     al,0bbh                 ; general failure
  97         stc
  98         jmp     short rest_exit_m
  99 ;
 100 rest_ok_m:
 101         popf
 102         pop     ax
 103 rest_exit_m:
 104 ;
 105         endm
 106 ;
 107 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 108 ;
 109 ;       3. MACRO to map a page in the physical page map onto a logical
 110 ;          page.
 111 ;
 112 ;       the map above page requires
 113 ;               mov     ah,44h
 114 ;               mov     dx,handle
 115 ;               mov     al,physical_page# (0-3)
 116 ;               mov     bx,logical_page#
 117 ;               int     67H
 118 ;       ah = 0 success and this routine zaps ax,dx and bx
 119 ;
 120 map_page        macro
 121 local   map_agn_m,map_exit_m,map_fin_m
 122 ;
 123         mov     ah,above_map    ; function map page
 124         mov     dx,cs:[above_pid]       ; get emm handle
 125 ;
 126         push    ax
 127 ;
 128 map_agn_m:
 129         pop     ax
 130         push    ax
 131         push    bx
 132         push    dx              ; "damn call above_map zaps these registers"
 133 ;
 134         int     67h             ; map call
 135         pop     dx
 136         pop     bx
 137 ;
 138         or      ah,ah           ; is there an error?
 139         jz      map_fin_m               ; if not go to finish up
 140 ;
 141 ;       error condition - check for recoverable error
 142 ;
 143         cmp     ah,above_error_busy     ; if manager was busy
 144         jz      map_agn_m                       ; we sure can try again
 145 ;
 146 ;       unrecoverable error
 147 ;
 148         pop     ax
 149         mov     al,0aah                 ; device not ready error
 150         stc
 151         jmp     short map_exit_m
 152 ;
 153 ;       exit point
 154 ;
 155 map_fin_m:
 156         clc
 157         pop     ax
 158 map_exit_m:
 159 ;
 160         endm
 161 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 162 ;
 163 ;                       OTHER MACROS
 164 ;
 165 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 166 ;
 167 ;       1) MACRO to switch es:di with ds:si
 168 ;
 169 src_dest_switch macro
 170 ;
 171         push    ds
 172         push    es
 173         push    si
 174         mov     si,di
 175         pop     di
 176         pop     ds
 177         pop     es
 178 ;
 179         endm
 180 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;