bsd/kern/mach_fat.c

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /* Copyright (c) 1991 NeXT Computer, Inc.  All rights reserved.
  23  *
  24  *      File:   kern/mach_fat.c
  25  *      Author: Peter King
  26  *
  27  *      Fat file support routines.
  28  *
  29  */
  30
  31 #include <sys/param.h>
  32 #include <sys/types.h>
  33 #include <sys/uio.h>
  34 #include <sys/vnode.h>
  35 #include <vm/vm_kern.h>
  36 #include <mach/kern_return.h>
  37 #include <mach/vm_param.h>
  38 #include <kern/cpu_number.h>
  39 #include <mach-o/fat.h>
  40 #include <kern/mach_loader.h>
  41 #include <architecture/byte_order.h>
  42
  43
  44 /**********************************************************************
  45  * Routine:     fatfile_getarch()
  46  *
  47  * Function:    Locate the architecture-dependant contents of a fat
  48  *              file that match this CPU.
  49  *
  50  * Args:        vp:             The vnode for the fat file.
  51  *              header:         A pointer to the fat file header.
  52  *              archret (out):  Pointer to fat_arch structure to hold
  53  *                              the results.
  54  *
  55  * Returns:     KERN_SUCCESS:   Valid architecture found.
  56  *              KERN_FAILURE:   No valid architecture found.
  57  **********************************************************************/
  58 load_return_t
  59 fatfile_getarch(
  60         struct vnode            *vp,
  61         vm_offset_t     data_ptr,
  62         struct fat_arch         *archret)
  63 {
  64         /* vm_pager_t           pager; */
  65         vm_offset_t             addr;
  66         vm_size_t               size;
  67         kern_return_t           kret;
  68         load_return_t           lret;
  69         struct machine_slot     *ms;
  70         struct fat_arch         *arch;
  71         struct fat_arch         *best_arch;
  72         int                     grade;
  73         int                     best_grade;
  74         int                     nfat_arch;
  75         int                     end_of_archs;
  76         struct proc *p = current_proc();                /* XXXX */
  77         struct fat_header       *header;
  78         off_t filesize;
  79
  80         /*
  81          *      Get the pager for the file.
  82          */
  83
  84         header = (struct fat_header *)data_ptr;
  85
  86         /*
  87          *      Map portion that must be accessible directly into
  88          *      kernel's map.
  89          */
  90         nfat_arch = NXSwapBigLongToHost(header->nfat_arch);
  91
  92         end_of_archs = sizeof(struct fat_header)
  93                 + nfat_arch * sizeof(struct fat_arch);
  94 #if 0
  95         filesize = ubc_getsize(vp);
  96         if (end_of_archs > (int)filesize)
  97                 return(LOAD_BADMACHO);
  98         }
  99 #endif
 100
 101         /* This is beacuse we are reading only 512 bytes */
 102
 103         if (end_of_archs > 512)
 104                 return(LOAD_BADMACHO);
 105         /*
 106          *      Round size of fat_arch structures up to page boundry.
 107          */
 108         size = round_page(end_of_archs);
 109         if (size <= 0)
 110                 return(LOAD_BADMACHO);
 111
 112         /*
 113          * Scan the fat_arch's looking for the best one.
 114          */
 115         addr = data_ptr;
 116         ms = &machine_slot[cpu_number()];
 117         best_arch = NULL;
 118         best_grade = 0;
 119         arch = (struct fat_arch *) (addr + sizeof(struct fat_header));
 120         for (; nfat_arch-- > 0; arch++) {
 121
 122                 /*
 123                  *      Check to see if right cpu type.
 124                  */
 125                 if(NXSwapBigIntToHost(arch->cputype) != ms->cpu_type)
 126                         continue;
 127
 128                 /*
 129                  *      Get the grade of the cpu subtype.
 130                  */
 131                 grade = grade_cpu_subtype(
 132                             NXSwapBigIntToHost(arch->cpusubtype));
 133
 134                 /*
 135                  *      Remember it if it's the best we've seen.
 136                  */
 137                 if (grade > best_grade) {
 138                         best_grade = grade;
 139                         best_arch = arch;
 140                 }
 141         }
 142
 143         /*
 144          *      Return our results.
 145          */
 146         if (best_arch == NULL) {
 147                 lret = LOAD_BADARCH;
 148         } else {
 149                 archret->cputype        =
 150                             NXSwapBigIntToHost(best_arch->cputype);
 151                 archret->cpusubtype     =
 152                             NXSwapBigIntToHost(best_arch->cpusubtype);
 153                 archret->offset         =
 154                             NXSwapBigLongToHost(best_arch->offset);
 155                 archret->size           =
 156                             NXSwapBigLongToHost(best_arch->size);
 157                 archret->align          =
 158                             NXSwapBigLongToHost(best_arch->align);
 159
 160                 lret = LOAD_SUCCESS;
 161         }
 162
 163         /*
 164          * Free the memory we allocated and return.
 165          */
 166         return(lret);
 167 }
 168
 169