kernel/asm.s

   1 /*   Yeah, i finally figure it out with a half day debugging.
   2  * when an interrupt happened with no pri changed, process wouldn't
   3  * push the OLD SS and OLD ESP in the following stack fragment. And
   4  * that also happened to WITH_ERROR_CODE interrupt.
   5  *
   6  *       So, if when we at pri ZERO, and do a var_a = var_b / 0 that ivoke
   7  * a divide_error interrupt, and it just push the the flag regsiter and
   8  * and cs register with eip where the interrupt happened. There is NO
   9  * OLD SS and OLD ESP, then the final handler die() will put wrong
  10  * information that the the value of SS:ESP is random and no rule.
  11  */
  12
  13
  14 /*
  15  * no ERROR_code fragment
  16 +--------+--------+
  17 |        | old ss |
  18 +--------+--------+
  19 |    old   esp    |
  20 +--------+--------+
  21 |    old  eflags  |
  22 +--------+--------+
  23 |        |  cs    |
  24 +--------+--------+
  25 |       eip       |0x34
  26 +--------+--------+
  27 |    c_fun_addr   |0x30
  28 +--------+--------+
  29 |       eax       |0x2c
  30 +--------+--------+
  31 |       ecx       |0x28
  32 +--------+--------+
  33 |       edx       |0x24
  34 +--------+--------+
  35 |       ebx       |0x20
  36 +--------+--------+
  37 |       esi       |0x1c
  38 +--------+--------+
  39 |       edi       |0x18
  40 +--------+--------+
  41 |       ebp       |0x14
  42 +--------+--------+
  43 |        |   ds   |0x10
  44 +--------+--------+
  45 |        |   es   |0x0c
  46 +--------+--------+
  47 |        |   fs   |0x08
  48 +--------+--------+
  49 | error_code(=0)  |0x04    that's the para needed to pass to handler function
  50 +--------+--------+
  51 |    ptr_to_eip   |0x00    the protype of handler is do_xxx(eip_addr, err_code)
  52 +--------+--------+
  53  *
  54  */
  55 .globl divide_error
  56 divide_error:
  57         pushl $do_divide_error
  58
  59 no_error_code:
  60         /* push all the reg first to protect data */
  61         pushl %eax
  62         pushl %ecx
  63         pushl %edx
  64         pushl %ebx
  65         pushl %edi
  66         pushl %esi
  67         pushl %ebp
  68         pushl %ds
  69         pushl %es
  70         pushl %fs
  71
  72         pushl $0                        # error code
  73         lea   0x30(%esp), %eax          # get the addr of eip as para ofdo_xx
  74         pushl %eax
  75         movl  0x30(%esp), %eax          # another para of do_xxx
  76         movl  $0x10,%edx
  77         movw %dx,%ds
  78         movw %dx,%es
  79         movw %dx,%fs
  80         call *%eax
  81         addl $8,%esp                    # pop the two para
  82
  83         popl %fs
  84         popl %es
  85         popl %ds
  86         popl %ebp
  87         popl %esi
  88         popl %edi
  89         popl %ebx
  90         popl %edx
  91         popl %ecx
  92         popl %eax
  93
  94         addl $4,%esp                    # pop the handler address
  95         iret
  96
  97 .globl debug
  98 debug:
  99         pushl $do_int3          # _do_debug
 100         jmp no_error_code
 101
 102 .globl nmi
 103 nmi:
 104         pushl $do_nmi
 105         jmp no_error_code
 106
 107 .globl int3
 108 int3:
 109         pushl $do_int3
 110         jmp no_error_code
 111
 112 .globl overflow
 113 overflow:
 114         pushl $do_overflow
 115         jmp no_error_code
 116
 117 .globl bounds
 118 bounds:
 119         pushl $do_bounds
 120         jmp no_error_code
 121
 122 .globl invalid_op
 123 invalid_op:
 124         pushl $do_invalid_op
 125         jmp no_error_code
 126
 127 .globl coprocessor_segment_overrun
 128 coprocessor_segment_overrun:
 129         pushl $do_coprocessor_segment_overrun
 130         jmp no_error_code
 131
 132 .globl reserved
 133 reserved:
 134         pushl $do_reserved
 135         jmp no_error_code
 136
 137 #irq13:
 138 #       pushl %eax
 139 #       xorb %al,%al
 140 #       outb %al,$0xF0
 141 #       movb $0x20,%al
 142 #       outb %al,$0x20
 143 #       jmp 1f
 144 #1:     jmp 1f
 145 #1:     outb %al,$0xA0
 146 #       popl %eax
 147 #       jmp coprocessor_error
 148
 149
 150
 151 /*
 152  * with ERROR_code fragment
 153 +--------+--------+
 154 |        | old ss |
 155 +--------+--------+
 156 |    old   eps    |
 157 +--------+--------+
 158 |    old  eflags  |
 159 +--------+--------+
 160 |        |  cs    |
 161 +--------+--------+
 162 |       eip       |0x38
 163 +--------+--------+
 164 |    error_code   |0x34
 165 +--------+--------+
 166 |    c_fun_addr   |0x30
 167 +--------+--------+
 168 |       eax       |0x2c
 169 +--------+--------+
 170 |       ecx       |0x28
 171 +--------+--------+
 172 |       edx       |0x24
 173 +--------+--------+
 174 |       ebx       |0x20
 175 +--------+--------+
 176 |       edi       |0x1c
 177 +--------+--------+
 178 |       esi       |0x18
 179 +--------+--------+
 180 |       ebp       |0x14
 181 +--------+--------+
 182 |        |   ds   |0x10
 183 +--------+--------+
 184 |        |   es   |0x0c
 185 +--------+--------+
 186 |        |   fs   |0x08
 187 +--------+--------+
 188 |    error_code   |0x04    that's the para needed to pass to handler function
 189 +--------+--------+
 190 |    ptr_to_eip   |0x00    the protype of handler is do_xxx(eip_addr, err_code)
 191 +--------+--------+
 192  *
 193  */
 194
 195 .globl double_fault
 196 double_fault:
 197         pushl $do_double_fault
 198 error_code:
 199
 200         pushl %eax
 201         pushl %ecx
 202         pushl %edx
 203         pushl %ebx
 204         pushl %edi
 205         pushl %esi
 206         pushl %ebp
 207         pushl %ds
 208         pushl %es
 209         pushl %fs
 210
 211         movl  0x30(%esp), %eax         # erro code
 212         pushl %eax
 213         lea   0x34(%esp), %eax         # ptr to eip
 214         pushl %eax
 215
 216         movl $0x10,%eax
 217         movw %ax,%ds
 218         movw %ax,%es
 219         movw %ax,%fs
 220         movl 0x30(%esp), %eax
 221         call *%eax
 222         addl $8,%esp
 223         pop %fs
 224         pop %es
 225         pop %ds
 226         popl %ebp
 227         popl %esi
 228         popl %edi
 229         popl %ebx
 230         popl %edx
 231         popl %ecx
 232         popl %eax
 233
 234         addl $8, %esp
 235         iret
 236
 237 .globl invalid_TSS
 238 invalid_TSS:
 239         pushl $do_invalid_TSS
 240         jmp error_code
 241
 242 .globl segment_not_present
 243 segment_not_present:
 244         pushl $do_segment_not_present
 245         jmp error_code
 246
 247 .globl stack_segment
 248 stack_segment:
 249         pushl $do_stack_segment
 250         jmp error_code
 251
 252 .globl general_protection
 253 general_protection:
 254         pushl $do_general_protection
 255         jmp error_code
 256
 257
 258 .globl read_eip
 259 read_eip:
 260   pop %eax
 261   jmp *%eax
 262
 263
 264 /*   i'm tried to make the timer work correct, so i move the
 265    interrupt handle here. hope it works. :)
 266 */
 267
 268 .globl timer_interrupt
 269 timer_interrupt:
 270         pushl %eax
 271         pushl %ecx
 272         pushl %edx
 273         pushl %ebx
 274         pushl %edi
 275         pushl %esi
 276         pushl %ebp
 277         pushl %ds
 278         pushl %es
 279         pushl %fs
 280
 281         incl timer_ticks
 282         movb $0x20,%al          # EOI to interrupt controller #1
 283         outb %al,$0x20
 284
 285         call do_timer
 286
 287         pop %fs
 288         pop %es
 289         pop %ds
 290         popl %ebp
 291         popl %esi
 292         popl %edi
 293         popl %ebx
 294         popl %edx
 295         popl %ecx
 296         popl %eax
 297
 298         iret
 299
 300 .globl floppy_interrupt
 301 floppy_interrupt:
 302         pushl %eax
 303         pushl %ecx
 304         pushl %edx
 305         pushl %ebx
 306         pushl %edi
 307         pushl %esi
 308         pushl %ebp
 309         pushl %ds
 310         pushl %es
 311         pushl %fs
 312
 313         call do_floppy
 314
 315         pop %fs
 316         pop %es
 317         pop %ds
 318         popl %ebp
 319         popl %esi
 320         popl %edi
 321         popl %ebx
 322         popl %edx
 323         popl %ecx
 324         popl %eax
 325
 326         iret
 327
 328 __NR_syscall = 0x03
 329
 330 .globl syscall_interrupt
 331 syscall_interrupt:
 332         pushl %eax
 333         pushl %ecx
 334         pushl %edx
 335         pushl %ebx
 336         pushl %edi
 337         pushl %esi
 338         pushl %ebp
 339         pushl %ds
 340         pushl %es
 341         pushl %fs
 342
 343         cmpl $__NR_syscall, %eax
 344         ja   bad_syscall
 345
 346         pushl %edx
 347         pushl %ecx
 348         pushl %ebx
 349         call *syscall_table(,%eax,4)
 350         addl $12, %esp
 351
 352 syscall_ret:
 353         pop %fs
 354         pop %es
 355         pop %ds
 356         popl %ebp
 357         popl %esi
 358         popl %edi
 359         popl %ebx
 360         popl %edx
 361         popl %ecx
 362         popl %eax
 363
 364         iret
 365
 366 bad_syscall:
 367         movl $-38, %eax         # ENOSYS
 368         jmp syscall_ret