osfmk/ppc/misc.c

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_OSREFERENCE_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.  The rights granted to you under the
  10  * License may not be used to create, or enable the creation or
  11  * redistribution of, unlawful or unlicensed copies of an Apple operating
  12  * system, or to circumvent, violate, or enable the circumvention or
  13  * violation of, any terms of an Apple operating system software license
  14  * agreement.
  15  *
  16  * Please obtain a copy of the License at
  17  * http://www.opensource.apple.com/apsl/ and read it before using this
  18  * file.
  19  *
  20  * The Original Code and all software distributed under the License are
  21  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  22  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  23  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  25  * Please see the License for the specific language governing rights and
  26  * limitations under the License.
  27  *
  28  * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
  29  */
  30 /*
  31  * @OSF_COPYRIGHT@
  32  */
  33 #if 0  // dead code
  34 #include <debug.h>
  35 #include <mach_debug.h>
  36
  37 #include <mach/ppc/thread_status.h>
  38 #include <mach/vm_types.h>
  39 #include <kern/thread.h>
  40 #include <kern/misc_protos.h>
  41 #include <ppc/proc_reg.h>
  42 #include <ppc/pmap.h>
  43 #include <ppc/misc_protos.h>
  44 #include <ppc/exception.h>
  45
  46 /*
  47  * copyin/out_multiple - the assembler copyin/out functions jump to C for
  48  * help when the copyin lies over a segment boundary. The C breaks
  49  * down the copy into two sub-copies and re-calls the assembler with
  50  * these sub-copies. Very rare occurrance. Warning: These functions are
  51  * called whilst active_thread->thread_recover is still set.
  52  */
  53
  54 extern boolean_t copyin_multiple(const char *src,
  55                                  char *dst,
  56                                  vm_size_t count);
  57
  58 boolean_t copyin_multiple(const char *src,
  59                           char *dst,
  60                           vm_size_t count)
  61 {
  62         const char *midpoint;
  63         vm_size_t first_count;
  64         boolean_t first_result;
  65
  66         /* Assert that we've been called because of a segment boundary,
  67          * this function is more expensive than the assembler, and should
  68          * only be called in this difficult case.
  69          */
  70         assert(((vm_offset_t)src & 0xF0000000) !=
  71                ((vm_offset_t)(src + count -1) & 0xF0000000));
  72
  73         /* TODO NMGS define sensible constants for segments, and apply
  74          * to C and assembler (assembler is much harder)
  75          */
  76         midpoint = (const char*) ((vm_offset_t)(src + count) & 0xF0000000);
  77         first_count = (midpoint - src);
  78
  79         first_result = copyin(CAST_USER_ADDR_T(src), dst, first_count);
  80
  81         /* If there was an error, stop now and return error */
  82         if (first_result != 0)
  83                 return first_result;
  84
  85         /* otherwise finish the job and return result */
  86         return copyin(CAST_USER_ADDR_T(midpoint), dst + first_count, count-first_count);
  87 }
  88
  89 extern int copyout_multiple(const char *src, char *dst, vm_size_t count);
  90
  91 int copyout_multiple(const char *src, char *dst, vm_size_t count)
  92 {
  93         char *midpoint;
  94         vm_size_t first_count;
  95         boolean_t first_result;
  96
  97         /* Assert that we've been called because of a segment boundary,
  98          * this function is more expensive than the assembler, and should
  99          * only be called in this difficult case. For copyout, the
 100          * segment boundary is on the dst
 101          */
 102         assert(((vm_offset_t)dst & 0xF0000000) !=
 103                ((vm_offset_t)(dst + count - 1) & 0xF0000000));
 104
 105         /* TODO NMGS define sensible constants for segments, and apply
 106          * to C and assembler (assembler is much harder)
 107          */
 108         midpoint = (char *) ((vm_offset_t)(dst + count) & 0xF0000000);
 109         first_count = (midpoint - dst);
 110
 111         first_result = copyout(src, CAST_USER_ADDR_T(dst), first_count);
 112
 113         /* If there was an error, stop now and return error */
 114         if (first_result != 0)
 115                 return first_result;
 116
 117         /* otherwise finish the job and return result */
 118
 119         return copyout(src + first_count, CAST_USER_ADDR_T(midpoint), count-first_count);
 120 }
 121 #endif // dead code
 122