libsyscall/os/tsd.h

   1 /*
   2  * Copyright (c) 2012 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
  29 #ifndef OS_TSD_H
  30 #define OS_TSD_H
  31
  32 #include <stdint.h>
  33
  34 /* The low nine slots of the TSD are reserved for libsyscall usage. */
  35 #define __TSD_RESERVED_BASE 0
  36 #define __TSD_RESERVED_MAX 9
  37
  38 #define __TSD_THREAD_SELF 0
  39 #define __TSD_ERRNO 1
  40 #define __TSD_MIG_REPLY 2
  41 #define __TSD_SEMAPHORE_CACHE 9
  42
  43
  44 __attribute__((always_inline))
  45 static __inline__ unsigned int
  46 _os_cpu_number(void)
  47 {
  48         /* Not yet implemented */
  49         return 0;
  50 }
  51
  52 #if defined(__i386__) || defined(__x86_64__)
  53
  54 #if defined(__has_attribute)
  55 #if __has_attribute(address_space)
  56 #define OS_GS_RELATIVE  __attribute__((address_space(256)))
  57 #endif
  58 #endif
  59
  60 #ifdef OS_GS_RELATIVE
  61 #define _os_tsd_get_base() ((void * OS_GS_RELATIVE *)0)
  62 #else
  63 __attribute__((always_inline))
  64 static __inline__ void*
  65 _os_tsd_get_direct(unsigned long slot)
  66 {
  67         void *ret;
  68         __asm__("mov %%gs:%1, %0" : "=r" (ret) : "m" (*(void **)(slot * sizeof(void *))));
  69         return ret;
  70 }
  71
  72 __attribute__((always_inline))
  73 static __inline__ int
  74 _os_tsd_set_direct(unsigned long slot, void *val)
  75 {
  76 #if defined(__i386__) && defined(__PIC__)
  77         __asm__("movl %1, %%gs:%0" : "=m" (*(void **)(slot * sizeof(void *))) : "rn" (val));
  78 #elif defined(__i386__) && !defined(__PIC__)
  79         __asm__("movl %1, %%gs:%0" : "=m" (*(void **)(slot * sizeof(void *))) : "ri" (val));
  80 #else
  81         __asm__("movq %1, %%gs:%0" : "=m" (*(void **)(slot * sizeof(void *))) : "rn" (val));
  82 #endif
  83         return 0;
  84 }
  85 #endif
  86
  87 #else
  88 #error _os_tsd_get_base not implemented on this architecture
  89 #endif
  90
  91 #ifdef _os_tsd_get_base
  92 __attribute__((always_inline))
  93 static __inline__ void*
  94 _os_tsd_get_direct(unsigned long slot)
  95 {
  96         return _os_tsd_get_base()[slot];
  97 }
  98
  99 __attribute__((always_inline))
 100 static __inline__ int
 101 _os_tsd_set_direct(unsigned long slot, void *val)
 102 {
 103         _os_tsd_get_base()[slot] = val;
 104         return 0;
 105 }
 106 #endif
 107
 108 extern void _thread_set_tsd_base(void *tsd_base);
 109
 110 #endif