osfmk/ppc/misc.c

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23 /*
  24  * @OSF_COPYRIGHT@
  25  */
  26 #if 0  // dead code
  27 #include <debug.h>
  28 #include <mach_debug.h>
  29
  30 #include <mach/ppc/thread_status.h>
  31 #include <mach/vm_types.h>
  32 #include <kern/thread.h>
  33 #include <kern/misc_protos.h>
  34 #include <ppc/proc_reg.h>
  35 #include <ppc/pmap.h>
  36 #include <ppc/misc_protos.h>
  37 #include <ppc/exception.h>
  38
  39 /*
  40  * copyin/out_multiple - the assembler copyin/out functions jump to C for
  41  * help when the copyin lies over a segment boundary. The C breaks
  42  * down the copy into two sub-copies and re-calls the assembler with
  43  * these sub-copies. Very rare occurrance. Warning: These functions are
  44  * called whilst active_thread->thread_recover is still set.
  45  */
  46
  47 extern boolean_t copyin_multiple(const char *src,
  48                                  char *dst,
  49                                  vm_size_t count);
  50
  51 boolean_t copyin_multiple(const char *src,
  52                           char *dst,
  53                           vm_size_t count)
  54 {
  55         const char *midpoint;
  56         vm_size_t first_count;
  57         boolean_t first_result;
  58
  59         /* Assert that we've been called because of a segment boundary,
  60          * this function is more expensive than the assembler, and should
  61          * only be called in this difficult case.
  62          */
  63         assert(((vm_offset_t)src & 0xF0000000) !=
  64                ((vm_offset_t)(src + count -1) & 0xF0000000));
  65
  66         /* TODO NMGS define sensible constants for segments, and apply
  67          * to C and assembler (assembler is much harder)
  68          */
  69         midpoint = (const char*) ((vm_offset_t)(src + count) & 0xF0000000);
  70         first_count = (midpoint - src);
  71
  72         first_result = copyin(CAST_USER_ADDR_T(src), dst, first_count);
  73
  74         /* If there was an error, stop now and return error */
  75         if (first_result != 0)
  76                 return first_result;
  77
  78         /* otherwise finish the job and return result */
  79         return copyin(CAST_USER_ADDR_T(midpoint), dst + first_count, count-first_count);
  80 }
  81
  82 extern int copyout_multiple(const char *src, char *dst, vm_size_t count);
  83
  84 int copyout_multiple(const char *src, char *dst, vm_size_t count)
  85 {
  86         char *midpoint;
  87         vm_size_t first_count;
  88         boolean_t first_result;
  89
  90         /* Assert that we've been called because of a segment boundary,
  91          * this function is more expensive than the assembler, and should
  92          * only be called in this difficult case. For copyout, the
  93          * segment boundary is on the dst
  94          */
  95         assert(((vm_offset_t)dst & 0xF0000000) !=
  96                ((vm_offset_t)(dst + count - 1) & 0xF0000000));
  97
  98         /* TODO NMGS define sensible constants for segments, and apply
  99          * to C and assembler (assembler is much harder)
 100          */
 101         midpoint = (char *) ((vm_offset_t)(dst + count) & 0xF0000000);
 102         first_count = (midpoint - dst);
 103
 104         first_result = copyout(src, CAST_USER_ADDR_T(dst), first_count);
 105
 106         /* If there was an error, stop now and return error */
 107         if (first_result != 0)
 108                 return first_result;
 109
 110         /* otherwise finish the job and return result */
 111
 112         return copyout(src + first_count, CAST_USER_ADDR_T(midpoint), count-first_count);
 113 }
 114 #endif // dead code
 115