kernel/arch/ia32/include/context.h

   1 /*
   2  * Copyright (c) 2001-2004 Jakub Jermar
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  * - Redistributions of source code must retain the above copyright
  10  *   notice, this list of conditions and the following disclaimer.
  11  * - Redistributions in binary form must reproduce the above copyright
  12  *   notice, this list of conditions and the following disclaimer in the
  13  *   documentation and/or other materials provided with the distribution.
  14  * - The name of the author may not be used to endorse or promote products
  15  *   derived from this software without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 /** @addtogroup ia32
  30  * @{
  31  */
  32 /** @file
  33  */
  34
  35 #ifndef KERN_ia32_CONTEXT_H_
  36 #define KERN_ia32_CONTEXT_H_
  37
  38 #include <arch/types.h>
  39
  40 #define STACK_ITEM_SIZE 4
  41
  42 /*
  43  * Both context_save() and context_restore() eat two doublewords from the stack.
  44  * First for pop of the saved register, second during ret instruction.
  45  *
  46  * One item is put onto stack to support get_stack_base().
  47  */
  48 #define SP_DELTA        (8+STACK_ITEM_SIZE)
  49
  50 /*
  51  * Only save registers that must be preserved across
  52  * function calls.
  53  */
  54 struct context {
  55         uintptr_t sp;
  56         uintptr_t pc;
  57         uint32_t ebx;
  58         uint32_t esi;
  59         uint32_t edi;
  60         uint32_t ebp;
  61         ipl_t ipl;
  62 } __attribute__ ((packed));
  63
  64 #endif
  65
  66 /** @}
  67  */