reactos/ntoskrnl/ke/i386/syscall.S

   1 /*
   2  *  ReactOS kernel
   3  *  Copyright (C) 2000  David Welch <welch@cwcom.net>
   4  *
   5  *  This program is free software; you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License as published by
   7  *  the Free Software Foundation; either version 2 of the License, or
   8  *  (at your option) any later version.
   9  *
  10  *  This program is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License
  16  *  along with this program; if not, write to the Free Software
  17  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  18  */
  19 /* $Id: syscall.S,v 1.16 2004/07/02 00:47:57 royce Exp $
  20  *
  21  * FILE:            ntoskrnl/hal/x86/syscall.s
  22  * PURPOSE:         2E trap handler
  23  * PROGRAMMER:      David Welch (david.welch@seh.ox.ac.uk)
  24  * UPDATE HISTORY:
  25  *                  ???
  26  */
  27
  28 #include <ddk/status.h>
  29 #include <internal/i386/segment.h>
  30 #include <internal/ps.h>
  31 #include <internal/i386/ke.h>
  32 #include <roscfg.h>
  33
  34 #define KernelMode  (0)
  35 #define UserMode    (1)
  36
  37 /*
  38  *
  39  */
  40 .globl KeReturnFromSystemCall
  41 .globl KeReturnFromSystemCallWithHook
  42 .globl _interrupt_handler2e
  43 _interrupt_handler2e:
  44
  45         /* Construct a trap frame on the stack */
  46
  47         /* Error code */
  48         pushl $0
  49         pushl %ebp
  50         pushl %ebx
  51         pushl %esi
  52         pushl %edi
  53         pushl %fs
  54         /* Load PCR selector into fs */
  55         movl  $PCR_SELECTOR, %ebx
  56         movl  %ebx, %fs
  57
  58         /* Save the old exception list */
  59         movl  %fs:KPCR_EXCEPTION_LIST, %ebx
  60         pushl %ebx
  61         /* Set the exception handler chain terminator */
  62         movl  $0xffffffff, %fs:KPCR_EXCEPTION_LIST
  63         /* Get a pointer to the current thread */
  64         movl  %fs:KPCR_CURRENT_THREAD, %esi
  65         /* Save the old previous mode */
  66         movl  $0, %ebx
  67         movb  %ss:KTHREAD_PREVIOUS_MODE(%esi), %bl
  68         pushl %ebx
  69         /* Set the new previous mode based on the saved CS selector */
  70         movl  0x24(%esp), %ebx
  71         andl  $0x0000FFFF, %ebx
  72         cmpl  $KERNEL_CS, %ebx
  73         jne   L1
  74         movb  $KernelMode, %ss:KTHREAD_PREVIOUS_MODE(%esi)
  75         jmp   L3
  76 L1:
  77         movb  $UserMode, %ss:KTHREAD_PREVIOUS_MODE(%esi)
  78 L3:
  79
  80         /* Save other registers */
  81         pushl %eax
  82         pushl %ecx
  83         pushl %edx
  84         pushl %ds
  85         pushl %es
  86         pushl %gs
  87         pushl $0     /* DR7 */
  88         pushl $0     /* DR6 */
  89         pushl $0     /* DR3 */
  90         pushl $0     /* DR2 */
  91         pushl $0     /* DR1 */
  92         pushl $0     /* DR0 */
  93         pushl $0     /* XXX: TempESP */
  94         pushl $0     /* XXX: TempCS */
  95         pushl $0     /* XXX: DebugPointer */
  96         pushl $0     /* XXX: DebugArgMark */
  97
  98 #ifdef DBG
  99         /* Trick gdb 6 into backtracing over the system call */
 100         movl  4(%ebp), %ebx
 101         pushl %ebx   /* DebugEIP */
 102         movl  (%ebp), %ebx
 103         pushl %ebx   /* DebugEBP */
 104 #else
 105         movl  0x60(%esp), %ebx
 106         pushl %ebx   /* DebugEIP */
 107         pushl %ebp   /* DebugEBP */
 108 #endif
 109
 110         /* Load the segment registers */
 111         movl  $KERNEL_DS, %ebx
 112         movl  %ebx, %ds
 113         movl  %ebx, %es
 114         movl  %ebx, %gs
 115
 116         /*
 117          * Save the old trap frame pointer over where we would save the EDX
 118          * register.
 119          */
 120         movl  KTHREAD_TRAP_FRAME(%esi), %ebx
 121         movl  %ebx, KTRAP_FRAME_EDX(%esp)
 122
 123         /*  Allocate new Kernel stack frame  */
 124         movl  %esp,%ebp
 125
 126         /* Save a pointer to the trap frame in the TCB */
 127         movl  %ebp, KTHREAD_TRAP_FRAME(%esi)
 128
 129         /*  Set ES to kernel segment  */
 130         movw  $KERNEL_DS,%bx
 131         movw  %bx,%es
 132
 133         /*  Users's current stack frame pointer is source  */
 134         movl  %edx,%esi
 135
 136         /*  Determine system service table to use  */
 137         cmpl  $0x0fff, %eax
 138         ja    new_useShadowTable
 139
 140         /*  Check to see if EAX is valid/inrange  */
 141         cmpl  %es:_KeServiceDescriptorTable + 8, %eax
 142         jbe   new_serviceInRange
 143         movl  $STATUS_INVALID_SYSTEM_SERVICE, %eax
 144         movl  %eax, KTRAP_FRAME_EAX(%ebp) /* save our return value in PKTRAP_FRAME->Eax */
 145         jmp   KeReturnFromSystemCall
 146
 147 new_serviceInRange:
 148
 149 #ifdef DBG
 150         /* GDB thinks the function starts here and
 151            wants a standard prolog, so let's give it */
 152         pushl %ebp
 153         movl  %esp,%ebp
 154         popl  %ebp
 155 #endif
 156
 157         /*  Allocate room for argument list from kernel stack  */
 158         movl  %es:_KeServiceDescriptorTable + 12, %ecx
 159         movb  %es:(%ecx, %eax), %cl
 160         movzx %cl, %ecx
 161         subl  %ecx, %esp
 162
 163         /*  Copy the arguments from the user stack to the kernel stack  */
 164         movl  %esp,%edi
 165         cld
 166         rep   movsb
 167
 168         /*  DS is now also kernel segment  */
 169         movw  %bx, %ds
 170
 171         /* Call system call hook */
 172         pushl %eax
 173         call  _KiSystemCallHook
 174         popl  %eax
 175
 176         /*  Make the system service call  */
 177         movl  %es:_KeServiceDescriptorTable, %ecx
 178         movl  %es:(%ecx, %eax, 4), %eax
 179         call  *%eax
 180         movl  %eax, KTRAP_FRAME_EAX(%ebp) /* save our return value in PKTRAP_FRAME->Eax */
 181
 182 #if CHECKED
 183         /*  Bump Service Counter  */
 184 #endif
 185
 186         jmp   KeDeallocateStackAndReturnFromSystemCallWithHook
 187
 188 new_useShadowTable:
 189
 190         subl  $0x1000, %eax
 191
 192         /*  Check to see if EAX is valid/inrange  */
 193         cmpl  %es:_KeServiceDescriptorTableShadow + 24, %eax
 194         jbe   new_shadowServiceInRange
 195         movl  $STATUS_INVALID_SYSTEM_SERVICE, %eax
 196         movl  %eax, KTRAP_FRAME_EAX(%ebp) /* save our return value in PKTRAP_FRAME->Eax */
 197         jmp   KeReturnFromSystemCall
 198
 199 new_shadowServiceInRange:
 200
 201 #ifdef DBG
 202         /* GDB thinks the function starts here and
 203            wants a standard prolog, so let's give it */
 204         pushl %ebp
 205         movl  %esp,%ebp
 206         popl  %ebp
 207 #endif
 208
 209         /*  Allocate room for argument list from kernel stack  */
 210         movl  %es:_KeServiceDescriptorTableShadow + 28, %ecx
 211         movb  %es:(%ecx, %eax), %cl
 212         movzx %cl, %ecx
 213         subl  %ecx, %esp
 214
 215         /*  Copy the arguments from the user stack to the kernel stack  */
 216         movl  %esp,%edi
 217         cld
 218         rep   movsb
 219
 220         /*  DS is now also kernel segment  */
 221         movw  %bx,%ds
 222
 223         /* Call system call hook */
 224 //      pushl %eax
 225 //      call  _KiSystemCallHook
 226 //      popl  %eax
 227
 228         /* Call service check routine */
 229         pushl %eax
 230         call  _KiServiceCheck
 231         popl  %eax
 232
 233         /*  Make the system service call  */
 234         movl  %es:_KeServiceDescriptorTableShadow + 16, %ecx
 235         movl  %es:(%ecx, %eax, 4), %eax
 236         call  *%eax
 237         movl  %eax, KTRAP_FRAME_EAX(%ebp) /* save our return value in PKTRAP_FRAME->Eax */
 238
 239 #if CHECKED
 240         /* Bump Service Counter  */
 241 #endif
 242
 243 KeDeallocateStackAndReturnFromSystemCallWithHook:
 244         /* Deallocate the kernel stack frame  */
 245         movl %ebp,%esp
 246
 247 KeReturnFromSystemCallWithHook:
 248         /* Call the post system call hook and deliver any pending APCs */
 249         pushl %esp
 250         call  _KiAfterSystemCallHook
 251         addl  $4,%esp
 252
 253 KeReturnFromSystemCall:
 254
 255         /* Restore the user context */
 256         /* Get a pointer to the current thread */
 257         movl  %fs:0x124, %esi
 258
 259         /* Restore the old trap frame pointer */
 260         movl  KTRAP_FRAME_EDX(%esp), %ebx
 261         movl  %ebx, KTHREAD_TRAP_FRAME(%esi)
 262
 263 KiRosTrapReturn:
 264
 265 #if 0
 266         mov   KTRAP_FRAME_RESERVED1(%ebp), %ax
 267         cmp   %ax, SSIDX_NTCONTINUE
 268         jnz   KeNoEpilogPrint
 269         movl  KTRAP_FRAME_ESP(%ebp), %ecx
 270         movl  KTRAP_FRAME_EBP(%ebp), %edx
 271         call  @KeRosPrintEspEbp@8
 272 KeNoEpilogPrint:
 273 #endif
 274
 275         /* Skip debug information and unsaved registers */
 276         addl  $0x30, %esp
 277         popl  %gs
 278         popl  %es
 279         popl  %ds
 280         popl  %edx
 281         popl  %ecx
 282         popl  %eax
 283
 284         /* Restore the old previous mode */
 285         popl  %ebx
 286         movb  %bl, %ss:KTHREAD_PREVIOUS_MODE(%esi)
 287
 288         /* Restore the old exception handler list */
 289         popl  %ebx
 290         movl  %ebx, %fs:KPCR_EXCEPTION_LIST
 291
 292         popl  %fs
 293         popl  %edi
 294         popl  %esi
 295         popl  %ebx
 296         popl  %ebp
 297         addl  $0x4, %esp  /* Ignore error code */
 298
 299         iret
 300
 301 /* R3: NOTE: This is part of my in-progress attempt at correcting NtContinue
 302  *           It is not being called, yet...
 303  */
 304 .globl @KeRosTrapReturn@8
 305 @KeRosTrapReturn@8:
 306
 307         /* point %esp to the trap frame to restore */
 308         movl  %ecx, %esp
 309         movl  %esp, %ebp
 310
 311         /* Call the post system call hook and deliver any pending APCs */
 312         pushl %esp
 313         call  _KiAfterSystemCallHook
 314         addl  $4,%esp
 315
 316         /* Restore the user context */
 317         /* Get a pointer to the current thread */
 318         movl  %fs:0x124, %esi
 319         /* Restore the old trap frame pointer */
 320         movl  %edx, KTHREAD_TRAP_FRAME(%esi)
 321
 322         jmp   KiRosTrapReturn;