osfmk/ppc/misc.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 /*
  23  * @OSF_COPYRIGHT@
  24  */
  25 #if 0  // dead code
  26 #include <debug.h>
  27 #include <mach_debug.h>
  28
  29 #include <mach/ppc/thread_status.h>
  30 #include <mach/vm_types.h>
  31 #include <kern/thread.h>
  32 #include <kern/misc_protos.h>
  33 #include <ppc/proc_reg.h>
  34 #include <ppc/pmap.h>
  35 #include <ppc/misc_protos.h>
  36 #include <ppc/exception.h>
  37
  38 /*
  39  * copyin/out_multiple - the assembler copyin/out functions jump to C for
  40  * help when the copyin lies over a segment boundary. The C breaks
  41  * down the copy into two sub-copies and re-calls the assembler with
  42  * these sub-copies. Very rare occurrance. Warning: These functions are
  43  * called whilst active_thread->thread_recover is still set.
  44  */
  45
  46 extern boolean_t copyin_multiple(const char *src,
  47                                  char *dst,
  48                                  vm_size_t count);
  49
  50 boolean_t copyin_multiple(const char *src,
  51                           char *dst,
  52                           vm_size_t count)
  53 {
  54         const char *midpoint;
  55         vm_size_t first_count;
  56         boolean_t first_result;
  57
  58         /* Assert that we've been called because of a segment boundary,
  59          * this function is more expensive than the assembler, and should
  60          * only be called in this difficult case.
  61          */
  62         assert(((vm_offset_t)src & 0xF0000000) !=
  63                ((vm_offset_t)(src + count -1) & 0xF0000000));
  64
  65         /* TODO NMGS define sensible constants for segments, and apply
  66          * to C and assembler (assembler is much harder)
  67          */
  68         midpoint = (const char*) ((vm_offset_t)(src + count) & 0xF0000000);
  69         first_count = (midpoint - src);
  70
  71         first_result = copyin(CAST_USER_ADDR_T(src), dst, first_count);
  72
  73         /* If there was an error, stop now and return error */
  74         if (first_result != 0)
  75                 return first_result;
  76
  77         /* otherwise finish the job and return result */
  78         return copyin(CAST_USER_ADDR_T(midpoint), dst + first_count, count-first_count);
  79 }
  80
  81 extern int copyout_multiple(const char *src, char *dst, vm_size_t count);
  82
  83 int copyout_multiple(const char *src, char *dst, vm_size_t count)
  84 {
  85         char *midpoint;
  86         vm_size_t first_count;
  87         boolean_t first_result;
  88
  89         /* Assert that we've been called because of a segment boundary,
  90          * this function is more expensive than the assembler, and should
  91          * only be called in this difficult case. For copyout, the
  92          * segment boundary is on the dst
  93          */
  94         assert(((vm_offset_t)dst & 0xF0000000) !=
  95                ((vm_offset_t)(dst + count - 1) & 0xF0000000));
  96
  97         /* TODO NMGS define sensible constants for segments, and apply
  98          * to C and assembler (assembler is much harder)
  99          */
 100         midpoint = (char *) ((vm_offset_t)(dst + count) & 0xF0000000);
 101         first_count = (midpoint - dst);
 102
 103         first_result = copyout(src, CAST_USER_ADDR_T(dst), first_count);
 104
 105         /* If there was an error, stop now and return error */
 106         if (first_result != 0)
 107                 return first_result;
 108
 109         /* otherwise finish the job and return result */
 110
 111         return copyout(src + first_count, CAST_USER_ADDR_T(midpoint), count-first_count);
 112 }
 113 #endif // dead code
 114