bsd/kern/mach_fat.c

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25 /* Copyright (c) 1991 NeXT Computer, Inc.  All rights reserved.
  26  *
  27  *      File:   kern/mach_fat.c
  28  *      Author: Peter King
  29  *
  30  *      Fat file support routines.
  31  *
  32  */
  33
  34 #include <sys/param.h>
  35 #include <sys/types.h>
  36 #include <sys/uio.h>
  37 #include <sys/vnode.h>
  38 #include <vm/vm_kern.h>
  39 #include <mach/kern_return.h>
  40 #include <mach/vm_param.h>
  41 #include <kern/cpu_number.h>
  42 #include <mach-o/fat.h>
  43 #include <kern/mach_loader.h>
  44 #include <architecture/byte_order.h>
  45
  46
  47 /**********************************************************************
  48  * Routine:     fatfile_getarch()
  49  *
  50  * Function:    Locate the architecture-dependant contents of a fat
  51  *              file that match this CPU.
  52  *
  53  * Args:        vp:             The vnode for the fat file.
  54  *              header:         A pointer to the fat file header.
  55  *              archret (out):  Pointer to fat_arch structure to hold
  56  *                              the results.
  57  *
  58  * Returns:     KERN_SUCCESS:   Valid architecture found.
  59  *              KERN_FAILURE:   No valid architecture found.
  60  **********************************************************************/
  61 load_return_t
  62 fatfile_getarch(
  63         struct vnode            *vp,
  64         vm_offset_t     data_ptr,
  65         struct fat_arch         *archret)
  66 {
  67         /* vm_pager_t           pager; */
  68         vm_offset_t             addr;
  69         vm_size_t               size;
  70         kern_return_t           kret;
  71         load_return_t           lret;
  72         struct machine_slot     *ms;
  73         struct fat_arch         *arch;
  74         struct fat_arch         *best_arch;
  75         int                     grade;
  76         int                     best_grade;
  77         int                     nfat_arch;
  78         int                     end_of_archs;
  79         struct fat_header       *header;
  80         off_t filesize;
  81
  82         /*
  83          *      Get the pager for the file.
  84          */
  85
  86         header = (struct fat_header *)data_ptr;
  87
  88         /*
  89          *      Map portion that must be accessible directly into
  90          *      kernel's map.
  91          */
  92         nfat_arch = NXSwapBigLongToHost(header->nfat_arch);
  93
  94         end_of_archs = sizeof(struct fat_header)
  95                 + nfat_arch * sizeof(struct fat_arch);
  96 #if 0
  97         filesize = ubc_getsize(vp);
  98         if (end_of_archs > (int)filesize) {
  99                 return(LOAD_BADMACHO);
 100         }
 101 #endif
 102
 103         /* This is beacuse we are reading only 512 bytes */
 104
 105         if (end_of_archs > 512)
 106                 return(LOAD_BADMACHO);
 107         /*
 108          *      Round size of fat_arch structures up to page boundry.
 109          */
 110         size = round_page_32(end_of_archs);
 111         if (size <= 0)
 112                 return(LOAD_BADMACHO);
 113
 114         /*
 115          * Scan the fat_arch's looking for the best one.
 116          */
 117         addr = data_ptr;
 118         ms = &machine_slot[cpu_number()];
 119         best_arch = NULL;
 120         best_grade = 0;
 121         arch = (struct fat_arch *) (addr + sizeof(struct fat_header));
 122         for (; nfat_arch-- > 0; arch++) {
 123
 124                 /*
 125                  *      Check to see if right cpu type.
 126                  */
 127                 if(NXSwapBigIntToHost(arch->cputype) != ms->cpu_type)
 128                         continue;
 129
 130                 /*
 131                  *      Get the grade of the cpu subtype.
 132                  */
 133                 grade = grade_cpu_subtype(
 134                             NXSwapBigIntToHost(arch->cpusubtype));
 135
 136                 /*
 137                  *      Remember it if it's the best we've seen.
 138                  */
 139                 if (grade > best_grade) {
 140                         best_grade = grade;
 141                         best_arch = arch;
 142                 }
 143         }
 144
 145         /*
 146          *      Return our results.
 147          */
 148         if (best_arch == NULL) {
 149                 lret = LOAD_BADARCH;
 150         } else {
 151                 archret->cputype        =
 152                             NXSwapBigIntToHost(best_arch->cputype);
 153                 archret->cpusubtype     =
 154                             NXSwapBigIntToHost(best_arch->cpusubtype);
 155                 archret->offset         =
 156                             NXSwapBigLongToHost(best_arch->offset);
 157                 archret->size           =
 158                             NXSwapBigLongToHost(best_arch->size);
 159                 archret->align          =
 160                             NXSwapBigLongToHost(best_arch->align);
 161
 162                 lret = LOAD_SUCCESS;
 163         }
 164
 165         /*
 166          * Free the memory we allocated and return.
 167          */
 168         return(lret);
 169 }
 170
 171