memdisk/memdisk.h

   1 /* ----------------------------------------------------------------------- *
   2  *
   3  *   Copyright 2001-2008 H. Peter Anvin - All Rights Reserved
   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, Inc., 53 Temple Place Ste 330,
   8  *   Boston MA 02111-1307, USA; either version 2 of the License, or
   9  *   (at your option) any later version; incorporated herein by reference.
  10  *
  11  * ----------------------------------------------------------------------- */
  12
  13 /*
  14  * memdisk.h
  15  *
  16  * Miscellaneous header definitions
  17  */
  18
  19 #ifndef MEMDISK_H
  20 #define MEMDISK_H
  21
  22 #include <stddef.h>
  23
  24 /* We use the com32 interface for calling 16-bit code */
  25 #include <com32.h>
  26
  27 /* define it only for i386 */
  28 #if __SIZEOF_POINTER__ == 4
  29 #define __cdecl __attribute__((cdecl,regparm(0)))
  30 #endif
  31
  32 void __cdecl intcall(uint8_t, com32sys_t *, com32sys_t *);
  33
  34 /* Structure passed in from the real-mode code */
  35 struct real_mode_args {
  36     uint32_t rm_return;
  37     uint32_t rm_intcall;
  38     uint32_t rm_bounce;
  39     uint32_t rm_base;
  40     uint32_t rm_handle_interrupt;
  41     uint32_t rm_gdt;
  42     uint32_t rm_size;
  43     uint32_t rm_pmjmp;
  44     uint32_t rm_rmjmp;
  45 };
  46 extern struct real_mode_args rm_args;
  47 #define sys_bounce ((void *)rm_args.rm_bounce)
  48
  49 /* This is the header in the boot sector/setup area */
  50 struct setup_header {
  51     char cmdline[0x1f1];
  52     uint8_t setup_secs;
  53     uint16_t syssize;
  54     uint16_t swap_dev;
  55     uint16_t ram_size;
  56     uint16_t vid_mode;
  57     uint16_t root_dev;
  58     uint16_t boot_flag;
  59     uint16_t jump;
  60     char header[4];
  61     uint16_t version;
  62     uint32_t realmode_swtch;
  63     uint32_t start_sys;
  64     uint8_t type_of_loader;
  65     uint8_t loadflags;
  66     uint16_t setup_move_size;
  67     uint32_t code32_start;
  68     uint32_t ramdisk_image;
  69     uint32_t ramdisk_size;
  70     uint32_t bootsect_kludge;
  71     uint16_t head_end_ptr;
  72     uint16_t pad1;
  73     uint32_t cmd_line_ptr;
  74     uint32_t initrd_addr_max;
  75     uint32_t esdi;
  76     uint32_t edx;
  77     uint32_t sssp;
  78     uint32_t csip;
  79 };
  80 #define shdr ((struct setup_header *)rm_args.rm_base)
  81
  82 /* Standard routines */
  83 void *memcpy(void *, const void *, size_t);
  84 void *memset(void *, int, size_t);
  85 void *memmove(void *, const void *, size_t);
  86
  87 #define strcpy(a,b)   __builtin_strcpy(a,b)
  88
  89 static inline size_t strlen(const char *__a)
  90 {
  91     const char *__D;
  92     size_t __c;
  93
  94 asm("repne;scasb":"=D"(__D), "=c"(__c)
  95 :       "D"(__a), "c"(-1), "a"(0), "m"(*__a));
  96
  97     return __D - __a - 1;
  98 }
  99
 100 /* memcpy() but returns a pointer to end of buffer */
 101 static inline void *mempcpy(void *__d, const void *__s, unsigned int __n)
 102 {
 103     memcpy(__d, __s, __n);
 104     return (void *)((char *)__d + __n);
 105 }
 106
 107 /* memcmp() */
 108 static inline int memcmp(const void *__a, const void *__b, unsigned int __n)
 109 {
 110     const unsigned char *__aa = __a;
 111     const unsigned char *__bb = __b;
 112     int __d;
 113
 114     while (__n--) {
 115         __d = *__bb++ - *__aa++;
 116         if (__d)
 117             return __d;
 118     }
 119
 120     return 0;
 121 }
 122
 123 static inline void sti(void)
 124 {
 125     asm volatile("sti");
 126 }
 127
 128 static inline void cli(void)
 129 {
 130     asm volatile("cli");
 131 }
 132
 133 /* Decompression */
 134 extern int check_zip(void *indata, uint32_t size, uint32_t * zbytes_p,
 135                      uint32_t * dbytes_p, uint32_t * orig_crc,
 136                      uint32_t * offset_p);
 137 extern void *unzip(void *indata, uint32_t zbytes, uint32_t dbytes,
 138                    uint32_t orig_crc, void *target);
 139
 140 #endif