libsyscall/custom/custom.s

   1 /*
   2  * Copyright (c) 1999-2015 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_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. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /* Copyright (c) 1992 NeXT Computer, Inc.  All rights reserved.
  29  */
  30
  31 #include "SYS.h"
  32
  33 #if defined(__i386__)
  34
  35 /*
  36  * i386 needs custom assembly to transform the return from syscalls
  37  * into a proper stack for a function call out to cerror{,_nocancel}.
  38  */
  39
  40 LABEL(tramp_cerror)
  41         mov             %esp, %edx
  42         andl    $0xfffffff0, %esp
  43         subl    $16, %esp
  44         movl    %edx, 4(%esp)
  45         movl    %eax, (%esp)
  46         CALL_EXTERN(_cerror)
  47         movl    4(%esp), %esp
  48         ret
  49
  50 LABEL(tramp_cerror_nocancel)
  51         mov             %esp, %edx
  52         andl    $0xfffffff0, %esp
  53         subl    $16, %esp
  54         movl    %edx, 4(%esp)
  55         movl    %eax, (%esp)
  56         CALL_EXTERN(_cerror_nocancel)
  57         movl    4(%esp), %esp
  58         ret
  59
  60 LABEL(__sysenter_trap)
  61         popl %edx
  62         movl %esp, %ecx
  63         sysenter
  64
  65         .globl _i386_get_ldt
  66         ALIGN
  67 _i386_get_ldt:
  68         movl    $6,%eax
  69         MACHDEP_SYSCALL_TRAP
  70         jnb             2f
  71         jmp             tramp_cerror
  72 2:      ret
  73
  74
  75         .globl _i386_set_ldt
  76         ALIGN
  77 _i386_set_ldt:
  78         movl    $5,%eax
  79         MACHDEP_SYSCALL_TRAP
  80         jnb             2f
  81         jmp             tramp_cerror
  82 2:      ret
  83
  84         ALIGN
  85         .globl __thread_set_tsd_base
  86 __thread_set_tsd_base:
  87         pushl   4(%esp)
  88         pushl   $0
  89         movl    $3,%eax
  90         MACHDEP_SYSCALL_TRAP
  91         addl    $8,%esp
  92         ret
  93
  94 #elif defined(__x86_64__)
  95
  96         .globl _i386_get_ldt
  97         ALIGN
  98 _i386_get_ldt:
  99         movl    $6,%eax
 100         MACHDEP_SYSCALL_TRAP
 101         jnb             2f
 102         movq    %rax, %rdi
 103         jmp             _cerror
 104 2:      ret
 105
 106
 107         .globl _i386_set_ldt
 108         ALIGN
 109 _i386_set_ldt:
 110         movl    $5,%eax
 111         MACHDEP_SYSCALL_TRAP
 112         jnb             2f
 113         movq    %rax, %rdi
 114         jmp             _cerror
 115 2:      ret
 116
 117         ALIGN
 118         .globl __thread_set_tsd_base
 119 __thread_set_tsd_base:
 120         movl    $0, %esi        // 0 as the second argument
 121         movl    $ SYSCALL_CONSTRUCT_MDEP(3), %eax       // Machine-dependent syscall number 3
 122         MACHDEP_SYSCALL_TRAP
 123         ret
 124
 125 #else
 126 #error unknown architecture
 127 #endif
 128
 129 .subsections_via_symbols