ppc/sys/fork.s

   1 /*
   2  * Copyright (c) 1999 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) 1992 NeXT Computer, Inc.  All rights reserved.
  26  *
  27  *      File:   libc/ppc/sys/fork.s
  28  *
  29  * HISTORY
  30  * 18-Nov-92  Ben Fathi (benf@next.com)
  31  *      Created from M88K sources
  32  *
  33  * 11-Jan-92  Peter King (king@next.com)
  34  *      Created from M68K sources
  35  */
  36
  37 #import <sys/syscall.h>
  38 #import <architecture/ppc/asm_help.h>
  39 #import <architecture/ppc/pseudo_inst.h>
  40 #import <mach/ppc/syscall_sw.h>
  41
  42 /* We use 8 bytes for LOCAL_VAR(1) and LOCAL_VAR(2) */
  43 NESTED(_fork, 8, 0, 0, 0)
  44         CALL_EXTERN(__cthread_fork_prepare)
  45 #if defined(__DYNAMIC__)
  46 .cstring
  47 LC1:
  48         .ascii  "__dyld_fork_prepare\0"
  49 .text
  50         .align 2
  51         mflr    r0
  52         bl      1f
  53 1:      mflr    r3
  54         mtlr    r0
  55         addis   r3,r3,ha16(LC1-1b)
  56         addi    r3,r3,lo16(LC1-1b)
  57         addi    r4,r1,LOCAL_VAR(1)
  58         bl      __dyld_func_lookup
  59         lwz     r3,LOCAL_VAR(1)(r1)
  60         mtspr   ctr,r3
  61         bctrl
  62 #endif
  63         li      r0,SYS_fork
  64         sc
  65         b       Lbotch                  // error return
  66
  67         cmpwi   r4,0
  68         beq     Lparent                 // parent, since a1 == 0 in parent,
  69                                         //                     1 in child
  70 #if defined(__DYNAMIC__)
  71 .cstring
  72 LC3:
  73         .ascii  "__dyld_fork_child\0"
  74 .text
  75         .align 2
  76         mflr    r0
  77         bl      1f
  78 1:      mflr    r3
  79         mtlr    r0
  80         addis   r3,r3,ha16(LC3-1b)
  81         addi    r3,r3,lo16(LC3-1b)
  82         addi    r4,r1,LOCAL_VAR(1)
  83         bl      __dyld_func_lookup
  84         lwz     r3,LOCAL_VAR(1)(r1)
  85         mtspr   ctr,r3
  86         bctrl
  87 #endif
  88         li      r3,0x0                  // clear cached pid in child
  89         REG_TO_EXTERN(r3,__current_pid)
  90         CALL_EXTERN(_fork_mach_init)
  91         CALL_EXTERN(__cthread_fork_child)
  92 #if defined(__DYNAMIC__)
  93 .cstring
  94 LC4:
  95         .ascii  "__dyld_fork_child_final\0"
  96 .text
  97         .align 2
  98         mflr    r0
  99         bl      1f
 100 1:      mflr    r3
 101         mtlr    r0
 102         addis   r3,r3,ha16(LC4-1b)
 103         addi    r3,r3,lo16(LC4-1b)
 104         addi    r4,r1,LOCAL_VAR(1)
 105         bl      __dyld_func_lookup
 106         lwz     r3,LOCAL_VAR(1)(r1)
 107         mtspr   ctr,r3
 108         bctrl
 109 #endif
 110
 111         li      r3,0
 112         b       Lreturn
 113
 114 Lparent:
 115 #if defined(__DYNAMIC__)
 116         stw     r3,LOCAL_VAR(2)(r1)     // save child pid
 117         mflr    r0
 118         bl      1f
 119 1:      mflr    r3
 120         mtlr    r0
 121         addis   r3,r3,ha16(LC2-1b)
 122         addi    r3,r3,lo16(LC2-1b)
 123         addi    r4,r1,LOCAL_VAR(1)
 124         bl      __dyld_func_lookup
 125         lwz     r3,LOCAL_VAR(1)(r1)
 126         mtspr   ctr,r3
 127         bctrl
 128 #endif
 129         CALL_EXTERN(__cthread_fork_parent)
 130 #if defined(__DYNAMIC__)
 131         lwz     r3,LOCAL_VAR(2)(r1)
 132 #endif
 133         b       Lreturn
 134
 135 Lbotch:
 136 #if defined(__DYNAMIC__)
 137 .cstring
 138 LC2:
 139         .ascii  "__dyld_fork_parent\0"
 140 .text
 141         .align 2
 142         stw     r3,LOCAL_VAR(2)(r1)     // save error value
 143         mflr    r0
 144         bl      1f
 145 1:      mflr    r3
 146         mtlr    r0
 147         addis   r3,r3,ha16(LC2-1b)
 148         addi    r3,r3,lo16(LC2-1b)
 149         addi    r4,r1,LOCAL_VAR(1)
 150         bl      __dyld_func_lookup
 151         lwz     r3,LOCAL_VAR(1)(r1)
 152         mtspr   ctr,r3
 153         bctrl
 154         lwz     r3,LOCAL_VAR(2)(r1)     // restore error value for cerror
 155
 156 #endif
 157         CALL_EXTERN(cerror)
 158         /*
 159          * We use cthread_fork_parent() to clean up after a fork error
 160          * (unlock cthreads and mailloc packages) so the parent
 161          * process can Malloc() after fork() errors without
 162          * deadlocking.
 163          */
 164         CALL_EXTERN_AGAIN(__cthread_fork_parent)
 165         li32    r3,-1                   // error return
 166 Lreturn:        RETURN
 167 END(_fork)
 168