sysdeps/unix/sysv/linux/kernel-features.h

   1 /* Set flags signalling availability of kernel features based on given
   2    kernel version number.
   3    Copyright (C) 1999-2009, 2010, 2011, 2012 Free Software Foundation, Inc.
   4    This file is part of the GNU C Library.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, see
  18    <http://www.gnu.org/licenses/>.  */
  19
  20 /* This file must not contain any C code.  At least it must be protected
  21    to allow using the file also in assembler files.  */
  22
  23 #ifndef __LINUX_KERNEL_VERSION
  24 /* We assume the worst; all kernels should be supported.  */
  25 # define __LINUX_KERNEL_VERSION 0
  26 #endif
  27
  28 /* We assume for __LINUX_KERNEL_VERSION the same encoding used in
  29    linux/version.h.  I.e., the major, minor, and subminor all get a
  30    byte with the major number being in the highest byte.  This means
  31    we can do numeric comparisons.
  32
  33    In the following we will define certain symbols depending on
  34    whether the describes kernel feature is available in the kernel
  35    version given by __LINUX_KERNEL_VERSION.  We are not always exactly
  36    recording the correct versions in which the features were
  37    introduced.  If somebody cares these values can afterwards be
  38    corrected.  */
  39
  40 /* The sendfile syscall was introduced in 2.2.0.  */
  41 #define __ASSUME_SENDFILE               1
  42
  43 /* Linux 2.3.39 introduced IPC64.  Except for powerpc.  Linux 2.4.0 on
  44    PPC introduced a correct IPC64.  But PowerPC64 does not support a
  45    separate 64-bit syscall, already 64-bit.  */
  46 #ifndef __powerpc64__
  47 # define __ASSUME_IPC64         1
  48 #endif
  49
  50 /* The changed st_ino field appeared in 2.4.0-test6.  However, SH is lame,
  51    and still does not have a 64-bit inode field.  */
  52 #ifndef __sh__
  53 # define __ASSUME_ST_INO_64_BIT         1
  54 #endif
  55
  56 /* The getdents64 syscall was introduced in 2.4.0-test7 (but later for
  57    MIPS n32).  */
  58 #define __ASSUME_GETDENTS64_SYSCALL     1
  59
  60 /* Beginning with 2.6.12 the clock and timer supports CPU clocks.  */
  61 #define __ASSUME_POSIX_CPU_TIMERS       1
  62
  63 /* The statfs64 syscalls are available in 2.5.74 (but not for alpha).  */
  64 #define __ASSUME_STATFS64       1
  65
  66 /* The utimes syscall has been available for some architectures
  67    forever.  For x86 it was introduced after 2.5.75, for x86-64,
  68    ppc, and ppc64 it was introduced in 2.6.0-test3, for s390 it was
  69    introduced in 2.6.21-rc5.  */
  70 #if defined __sparc__ \
  71     || defined __i386__ \
  72     || defined __x86_64__ \
  73     || defined __powerpc__ \
  74     || defined __sh__ \
  75     || (defined __s390__ && __LINUX_KERNEL_VERSION >= 0x020616)
  76 # define __ASSUME_UTIMES        1
  77 #endif
  78
  79 /* pselect/ppoll were introduced just after 2.6.16-rc1.  Due to the way
  80    the kernel versions are advertised we can only rely on 2.6.17 to have
  81    the code.  On x86_64 and SH this appeared first in 2.6.19-rc1,
  82    on ia64 in 2.6.22-rc1.  */
  83 #if __LINUX_KERNEL_VERSION >= 0x020611 \
  84     && ((!defined __x86_64__ && !defined __sh__) \
  85         || (__LINUX_KERNEL_VERSION >= 0x020613 \
  86             && (defined __x86_64__ || defined __sh__)))
  87 # define __ASSUME_PSELECT       1
  88 # define __ASSUME_PPOLL         1
  89 #endif
  90
  91 /* The *at syscalls were introduced just after 2.6.16-rc1.  Due to the way the
  92    kernel versions are advertised we can only rely on 2.6.17 to have
  93    the code.  On PPC they were introduced in 2.6.17-rc1,
  94    on SH in 2.6.19-rc1.  */
  95 #if __LINUX_KERNEL_VERSION >= 0x020611 \
  96     && (!defined __sh__ || __LINUX_KERNEL_VERSION >= 0x020613)
  97 # define __ASSUME_ATFCTS        1
  98 #endif
  99
 100 /* Support for inter-process robust mutexes was added in 2.6.17.  */
 101 #if __LINUX_KERNEL_VERSION >= 0x020611 \
 102     && (!defined __sh__ || __LINUX_KERNEL_VERSION >= 0x020613)
 103 # define __ASSUME_SET_ROBUST_LIST       1
 104 #endif
 105
 106 /* Pessimistically assume that 2.6.18 introduced real handling of
 107    large numbers of requests to readv and writev and that we don't
 108    need a fallback.  It likely worked for much longer.  */
 109 #if __LINUX_KERNEL_VERSION >= 0x020612
 110 # define __ASSUME_COMPLETE_READV_WRITEV 1
 111 #endif
 112
 113 /* Support for PI futexes was added in 2.6.18.  */
 114 #if __LINUX_KERNEL_VERSION >= 0x020612
 115 # define __ASSUME_FUTEX_LOCK_PI 1
 116 #endif
 117
 118 /* Support for utimensat syscall was added in 2.6.22, on SH
 119    only after 2.6.22-rc1.  */
 120 #if __LINUX_KERNEL_VERSION >= 0x020616 \
 121     && (!defined __sh__ || __LINUX_KERNEL_VERSION >= 0x020617)
 122 # define __ASSUME_UTIMENSAT     1
 123 #endif
 124
 125 /* Support for private futexes was added in 2.6.22.  */
 126 #if __LINUX_KERNEL_VERSION >= 0x020616
 127 # define __ASSUME_PRIVATE_FUTEX 1
 128 #endif
 129
 130 /* Support for fallocate was added in 2.6.23, on s390
 131    only after 2.6.23-rc1.  */
 132 #if __LINUX_KERNEL_VERSION >= 0x020617 \
 133     && (!defined __s390__ || __LINUX_KERNEL_VERSION >= 0x020618)
 134 # define __ASSUME_FALLOCATE     1
 135 #endif
 136
 137 /* Support for various CLOEXEC and NONBLOCK flags was added for x86,
 138    x86-64, PPC, IA-64, SPARC< and S390 in 2.6.23.  */
 139 #if __LINUX_KERNEL_VERSION >= 0x020617 \
 140     && (defined __i386__ || defined __x86_64__ || defined __powerpc__ \
 141         || defined __sparc__ || defined __s390__)
 142 # define __ASSUME_O_CLOEXEC     1
 143 #endif
 144
 145 /* From 2.6.23 onwards the value of ARG_MAX depends on the stack
 146    size.  */
 147 #define __LINUX_ARG_MAX_STACK_BASED_MIN_KERNEL  0x020617
 148 #if __LINUX_KERNEL_VERSION >= __LINUX_ARG_MAX_STACK_BASED_MIN_KERNEL
 149 # define __ASSUME_ARG_MAX_STACK_BASED   1
 150 #endif
 151
 152 /* Support for ADJ_OFFSET_SS_READ was added in 2.6.24.  */
 153 #if __LINUX_KERNEL_VERSION >= 0x020618
 154 # define __ASSUME_ADJ_OFFSET_SS_READ    1
 155 #endif
 156
 157 /* Support for various CLOEXEC and NONBLOCK flags was added for x86,
 158    x86-64, PPC, IA-64, and SPARC in 2.6.27.  */
 159 #if __LINUX_KERNEL_VERSION >= 0x02061b \
 160     && (defined __i386__ || defined __x86_64__ || defined __powerpc__ \
 161         || defined __sparc__ || defined __s390__)
 162 # define __ASSUME_SOCK_CLOEXEC  1
 163 # define __ASSUME_IN_NONBLOCK   1
 164 # define __ASSUME_PIPE2         1
 165 # define __ASSUME_EVENTFD2      1
 166 # define __ASSUME_SIGNALFD4     1
 167 # define __ASSUME_DUP3          1
 168 #endif
 169
 170 /* Support for the accept4 syscall was added in 2.6.28.  */
 171 #if __LINUX_KERNEL_VERSION >= 0x02061c \
 172     && (defined __i386__ || defined __x86_64__ || defined __powerpc__ \
 173         || defined __sparc__ || defined __s390__)
 174 # define __ASSUME_ACCEPT4       1
 175 #endif
 176
 177 /* Support for the FUTEX_CLOCK_REALTIME flag was added in 2.6.29.  */
 178 #if __LINUX_KERNEL_VERSION >= 0x02061d
 179 # define __ASSUME_FUTEX_CLOCK_REALTIME  1
 180 #endif
 181
 182 /* Support for the AT_RANDOM auxiliary vector entry was added in 2.6.29.  */
 183 #if __LINUX_KERNEL_VERSION >= 0x02061d
 184 # define __ASSUME_AT_RANDOM     1
 185 #endif
 186
 187 /* Support for preadv and pwritev was added in 2.6.30.  */
 188 #if __LINUX_KERNEL_VERSION >= 0x02061e
 189 # define __ASSUME_PREADV        1
 190 # define __ASSUME_PWRITEV       1
 191 #endif
 192
 193 /* Support for F_GETOWN_EX was introduced in 2.6.32.  */
 194 #if __LINUX_KERNEL_VERSION >= 0x020620
 195 # define __ASSUME_F_GETOWN_EX   1
 196 #endif
 197
 198 /* Support for the recvmmsg syscall was added in 2.6.33.  */
 199 #if __LINUX_KERNEL_VERSION >= 0x020621
 200 # define __ASSUME_RECVMMSG      1
 201 #endif
 202
 203 /* statfs fills in f_flags since 2.6.36.  */
 204 #if __LINUX_KERNEL_VERSION >= 0x020624
 205 # define __ASSUME_STATFS_F_FLAGS        1
 206 #endif
 207
 208 /* prlimit64 is available in 2.6.36.  */
 209 #if __LINUX_KERNEL_VERSION >= 0x020624
 210 # define __ASSUME_PRLIMIT64     1
 211 #endif
 212
 213 /* sendmmsg is available in 2.6.39.  */
 214 #if __LINUX_KERNEL_VERSION >= 0x020627
 215 # define __ASSUME_SENDMMSG      1
 216 #endif
 217
 218 /* getcpu is a syscall for x86-64 since 3.1.  */
 219 #if defined __x86_64__ && __LINUX_KERNEL_VERSION >= 0x030100
 220 # define __ASSUME_GETCPU_SYSCALL        1
 221 #endif