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.  Most of the numbers here are set corresponding to
  39    2.2.0.  */
  40
  41 /* `getcwd' system call.  */
  42 #if __LINUX_KERNEL_VERSION >= 131584
  43 # define __ASSUME_GETCWD_SYSCALL        1
  44 #endif
  45
  46 /* Real-time signal became usable in 2.1.70.  */
  47 #if __LINUX_KERNEL_VERSION >= 131398
  48 # define __ASSUME_REALTIME_SIGNALS      1
  49 #endif
  50
  51 /* When were the `pread'/`pwrite' syscalls introduced?  */
  52 #if __LINUX_KERNEL_VERSION >= 131584
  53 # define __ASSUME_PREAD_SYSCALL         1
  54 # define __ASSUME_PWRITE_SYSCALL        1
  55 #endif
  56
  57 /* When was `poll' introduced?  */
  58 #if __LINUX_KERNEL_VERSION >= 131584
  59 # define __ASSUME_POLL_SYSCALL          1
  60 #endif
  61
  62 /* The `lchown' syscall was introduced in 2.1.80.  */
  63 #if __LINUX_KERNEL_VERSION >= 131408
  64 # define __ASSUME_LCHOWN_SYSCALL        1
  65 #endif
  66
  67 /* When did the `setresuid' syscall became available?  */
  68 #if __LINUX_KERNEL_VERSION >= 131584 && !defined __sparc__
  69 # define __ASSUME_SETRESUID_SYSCALL     1
  70 #endif
  71
  72 /* The SIOCGIFNAME ioctl is available starting with 2.1.50.  */
  73 #if __LINUX_KERNEL_VERSION >= 131408
  74 # define __ASSUME_SIOCGIFNAME           1
  75 #endif
  76
  77 /* MSG_NOSIGNAL was at least available with Linux 2.2.0.  */
  78 #if __LINUX_KERNEL_VERSION >= 131584
  79 # define __ASSUME_MSG_NOSIGNAL          1
  80 #endif
  81
  82 /* The sendfile syscall was introduced in 2.2.0.  */
  83 #if __LINUX_KERNEL_VERSION >= 131584
  84 # define __ASSUME_SENDFILE              1
  85 #endif
  86
  87 /* Only very old kernels had no real symlinks for terminal descriptors
  88    in /proc/self/fd.  */
  89 #if __LINUX_KERNEL_VERSION >= 131584
  90 # define __ASSUME_PROC_SELF_FD_SYMLINK  1
  91 #endif
  92
  93 /* On x86 another `getrlimit' syscall was added in 2.3.25.  */
  94 #if __LINUX_KERNEL_VERSION >= 131865 && defined __i386__
  95 # define __ASSUME_NEW_GETRLIMIT_SYSCALL 1
  96 #endif
  97
  98 /* On x86 the truncate64/ftruncate64 syscalls were introduced in 2.3.31.  */
  99 #if __LINUX_KERNEL_VERSION >= 131871 && defined __i386__
 100 # define __ASSUME_TRUNCATE64_SYSCALL    1
 101 #endif
 102
 103 /* On x86 the mmap2 syscall was introduced in 2.3.31.  */
 104 #if __LINUX_KERNEL_VERSION >= 131871 && defined __i386__
 105 # define __ASSUME_MMAP2_SYSCALL 1
 106 #endif
 107
 108 /* On x86 the stat64/lstat64/fstat64 syscalls were introduced in 2.3.34.  */
 109 #if __LINUX_KERNEL_VERSION >= 131874 && defined __i386__
 110 # define __ASSUME_STAT64_SYSCALL        1
 111 #endif
 112
 113 /* On sparc the truncate64/ftruncate64/mmap2/stat64/lstat64/fstat64
 114    syscalls were introduced in 2.3.35.  */
 115 #if __LINUX_KERNEL_VERSION >= 131875 \
 116     && (defined __sparc__ && !defined __arch64__)
 117 # define __ASSUME_TRUNCATE64_SYSCALL    1
 118 # define __ASSUME_MMAP2_SYSCALL         1
 119 # define __ASSUME_STAT64_SYSCALL        1
 120 #endif
 121
 122 /* I know for sure that getrlimit are in 2.3.35 on powerpc.  */
 123 #if __LINUX_KERNEL_VERSION >= 131875 && defined __powerpc__
 124 # define __ASSUME_NEW_GETRLIMIT_SYSCALL 1
 125 #endif
 126
 127 /* I know for sure that these are in 2.3.35 on powerpc. But PowerPC64 does not
 128    support separate 64-bit syscalls, already 64-bit.  */
 129 #if __LINUX_KERNEL_VERSION >= 131875 && defined __powerpc__ \
 130     && !defined __powerpc64__
 131 # define __ASSUME_TRUNCATE64_SYSCALL    1
 132 # define __ASSUME_STAT64_SYSCALL        1
 133 #endif
 134
 135 /* Linux 2.3.39 introduced 32bit UID/GIDs.  Some platforms had 32
 136    bit type all along.  */
 137 #if __LINUX_KERNEL_VERSION >= 131879 || defined __powerpc__
 138 # define __ASSUME_32BITUIDS             1
 139 #endif
 140
 141 /* Linux 2.3.39 sparc added setresuid.  */
 142 #if __LINUX_KERNEL_VERSION >= 131879 && defined __sparc__
 143 # define __ASSUME_SETRESUID_SYSCALL     1
 144 #endif
 145
 146 #if __LINUX_KERNEL_VERSION >= 131879
 147 # define __ASSUME_SETRESGID_SYSCALL     1
 148 #endif
 149
 150 /* Linux 2.3.39 introduced IPC64.  Except for powerpc.  */
 151 #if __LINUX_KERNEL_VERSION >= 131879 && !defined __powerpc__
 152 # define __ASSUME_IPC64         1
 153 #endif
 154
 155 /* We can use the LDTs for threading with Linux 2.3.99 and newer.  */
 156 #if __LINUX_KERNEL_VERSION >= 131939
 157 # define __ASSUME_LDT_WORKS             1
 158 #endif
 159
 160 /* Linux 2.4.0 on PPC introduced a correct IPC64.  But PowerPC64 does not
 161    support a separate 64-bit syscall, already 64-bit.  */
 162 #if __LINUX_KERNEL_VERSION >= 132096 && defined __powerpc__ \
 163     && !defined __powerpc64__
 164 # define __ASSUME_IPC64                 1
 165 #endif
 166
 167 /* SH kernels got stat64, mmap2, and truncate64 during 2.4.0-test.  */
 168 #if __LINUX_KERNEL_VERSION >= 132096 && defined __sh__
 169 # define __ASSUME_TRUNCATE64_SYSCALL    1
 170 # define __ASSUME_MMAP2_SYSCALL         1
 171 # define __ASSUME_STAT64_SYSCALL        1
 172 #endif
 173
 174 /* The changed st_ino field appeared in 2.4.0-test6.  But we cannot
 175    distinguish this version from other 2.4.0 releases.  Therefore play
 176    save and assume it available is for 2.4.1 and up.  However, SH is lame,
 177    and still does not have a 64-bit inode field.  */
 178 #if __LINUX_KERNEL_VERSION >= 132097 && !defined __sh__
 179 # define __ASSUME_ST_INO_64_BIT         1
 180 #endif
 181
 182 /* To support locking of large files a new fcntl() syscall was introduced
 183    in 2.4.0-test7.  We test for 2.4.1 for the earliest version we know
 184    the syscall is available.  */
 185 #if __LINUX_KERNEL_VERSION >= 132097 && (defined __i386__ || defined __sparc__)
 186 # define __ASSUME_FCNTL64               1
 187 #endif
 188
 189 /* The AT_CLKTCK auxiliary vector entry was introduction in the 2.4.0
 190    series.  */
 191 #if __LINUX_KERNEL_VERSION >= 132097
 192 # define __ASSUME_AT_CLKTCK             1
 193 #endif
 194
 195 /* Arm got fcntl64 in 2.4.4, PowerPC and SH have it also in 2.4.4 (I
 196    don't know when it got introduced).  But PowerPC64 does not support
 197    separate FCNTL64 call, FCNTL is already 64-bit */
 198 #if __LINUX_KERNEL_VERSION >= 132100 \
 199     && (defined __powerpc__ || defined __sh__) \
 200     && !defined __powerpc64__
 201 # define __ASSUME_FCNTL64               1
 202 #endif
 203
 204 /* The getdents64 syscall was introduced in 2.4.0-test7.  We test for
 205    2.4.1 for the earliest version we know the syscall is available.  */
 206 #if __LINUX_KERNEL_VERSION >= 132097
 207 # define __ASSUME_GETDENTS64_SYSCALL    1
 208 #endif
 209
 210 /* When did O_DIRECTORY become available?  Early in 2.3 but when?
 211    Be safe, use 2.3.99.  */
 212 #if __LINUX_KERNEL_VERSION >= 131939
 213 # define __ASSUME_O_DIRECTORY           1
 214 #endif
 215
 216 /* Starting with one of the 2.4.0 pre-releases the Linux kernel passes
 217    up the page size information.  */
 218 #if __LINUX_KERNEL_VERSION >= 132097
 219 # define __ASSUME_AT_PAGESIZE           1
 220 #endif
 221
 222 /* Starting with at least 2.4.0 the kernel passes the uid/gid unconditionally
 223    up to the child.  */
 224 #if __LINUX_KERNEL_VERSION >= 132097
 225 # define __ASSUME_AT_XID                1
 226 #endif
 227
 228 /* Starting with 2.4.5 kernels PPC passes the AUXV in the standard way
 229    and the vfork syscall made it into the official kernel.  */
 230 #if __LINUX_KERNEL_VERSION >= (132096+5) && defined __powerpc__
 231 # define __ASSUME_STD_AUXV              1
 232 # define __ASSUME_VFORK_SYSCALL         1
 233 #endif
 234
 235 /* Starting with 2.4.5 kernels the mmap2 syscall made it into the official
 236    kernel.  But PowerPC64 does not support a separate MMAP2 call.  */
 237 #if __LINUX_KERNEL_VERSION >= (132096+5) && defined __powerpc__ \
 238     && !defined __powerpc64__
 239 # define __ASSUME_MMAP2_SYSCALL         1
 240 #endif
 241
 242 /* Starting with 2.4.21 PowerPC implements the new prctl syscall.
 243    This allows applications to get/set the Floating Point Exception Mode.  */
 244 #if __LINUX_KERNEL_VERSION >= (132096+21) && defined __powerpc__
 245 # define __ASSUME_NEW_PRCTL_SYSCALL             1
 246 #endif
 247
 248 /* Starting with 2.4.21 the PowerPC32 clone syscall works as expected.  */
 249 #if __LINUX_KERNEL_VERSION >= (132096+21) && defined __powerpc__ \
 250     && !defined __powerpc64__
 251 # define __ASSUME_FIXED_CLONE_SYSCALL           1
 252 #endif
 253
 254 /* Starting with 2.4.21 PowerPC64 implements the new rt_sigreturn syscall.
 255    The new rt_sigreturn takes an ucontext pointer allowing rt_sigreturn
 256    to be used in the set/swapcontext implementation.  */
 257 #if __LINUX_KERNEL_VERSION >= (132096+21) && defined __powerpc64__
 258 # define __ASSUME_NEW_RT_SIGRETURN_SYSCALL              1
 259 #endif
 260
 261 /* On x86, the set_thread_area syscall was introduced in 2.5.29, but its
 262    semantics was changed in 2.5.30, and again after 2.5.31.  */
 263 #if __LINUX_KERNEL_VERSION >= 132384 && defined __i386__
 264 # define __ASSUME_SET_THREAD_AREA_SYSCALL       1
 265 #endif
 266
 267 /* The vfork syscall on x86 and arm was definitely available in 2.4.  */
 268 #if __LINUX_KERNEL_VERSION >= 132097 && defined __i386__
 269 # define __ASSUME_VFORK_SYSCALL         1
 270 #endif
 271
 272 /* The late 2.5 kernels saw a lot of new CLONE_* flags.  Summarize
 273    their availability with one define.  The changes were made first
 274    for i386 and the have to be done separately for the other archs.
 275    For i386 we pick 2.5.50 as the first version with support.
 276    For s390*, PPC, x86-64, and SH we pick 2.5.64 as the first
 277    version with support.  */
 278 #if ((__LINUX_KERNEL_VERSION >= 132402 && defined __i386__)             \
 279      || (__LINUX_KERNEL_VERSION >= 132416                               \
 280          && (defined __s390__                   \
 281              || defined __powerpc__ || defined __x86_64__ || defined __sh__)))
 282 # define __ASSUME_CLONE_THREAD_FLAGS    1
 283 #endif
 284
 285 /* Beginning with 2.5.63 support for realtime and monotonic clocks and
 286    timers based on them is available.  */
 287 #if __LINUX_KERNEL_VERSION >= 132415
 288 # define __ASSUME_POSIX_TIMERS          1
 289 #endif
 290
 291 /* Beginning with 2.6.12 the clock and timer supports CPU clocks.  */
 292 #if __LINUX_KERNEL_VERSION >= 0x2060c
 293 # define __ASSUME_POSIX_CPU_TIMERS      1
 294 #endif
 295
 296 /* With kernel 2.4.17 we always have netlink support.  */
 297 #if __LINUX_KERNEL_VERSION >= (132096+17)
 298 # define __ASSUME_NETLINK_SUPPORT       1
 299 #endif
 300
 301 /* The requeue futex functionality was introduced in 2.5.70.  */
 302 #if __LINUX_KERNEL_VERSION >= 132422
 303 # define __ASSUME_FUTEX_REQUEUE 1
 304 #endif
 305
 306 /* The statfs64 syscalls are available in 2.5.74.  */
 307 #if __LINUX_KERNEL_VERSION >= 132426
 308 # define __ASSUME_STATFS64      1
 309 #endif
 310
 311 /* Starting with at least 2.5.74 the kernel passes the setuid-like exec
 312    flag unconditionally up to the child.  */
 313 #if __LINUX_KERNEL_VERSION >= 132426
 314 # define __ASSUME_AT_SECURE     1
 315 #endif
 316
 317 /* Starting with the 2.5.75 kernel the kernel fills in the correct value
 318    in the si_pid field passed as part of the siginfo_t struct to signal
 319    handlers.  */
 320 #if __LINUX_KERNEL_VERSION >= 132427
 321 # define __ASSUME_CORRECT_SI_PID        1
 322 #endif
 323
 324 /* The tgkill syscall was instroduced for i386 in 2.5.75.  On x86-64,
 325    ppc, and ppc64 it was introduced in 2.6.0-test3. */
 326 #if (__LINUX_KERNEL_VERSION >= 132427 && defined __i386__) \
 327     || (__LINUX_KERNEL_VERSION >= 132609 && defined __x86_64__) \
 328     || (__LINUX_KERNEL_VERSION >= 132609 && defined __powerpc__) \
 329     || (__LINUX_KERNEL_VERSION >= 132609 && defined __sh__)
 330 # define __ASSUME_TGKILL        1
 331 #endif
 332
 333 /* The utimes syscall has been available for some architectures
 334    forever.  For x86 it was introduced after 2.5.75, for x86-64,
 335    ppc, and ppc64 it was introduced in 2.6.0-test3.  */
 336 #if defined __sparc__ \
 337     || (__LINUX_KERNEL_VERSION > 132427 && defined __i386__) \
 338     || (__LINUX_KERNEL_VERSION > 132609 && defined __x86_64__) \
 339     || (__LINUX_KERNEL_VERSION >= 132609 && defined __powerpc__) \
 340     || (__LINUX_KERNEL_VERSION >= 132609 && defined __sh__)
 341 # define __ASSUME_UTIMES        1
 342 #endif
 343
 344 // XXX Disabled for now since the semantics we want is not achieved.
 345 #if 0
 346 /* The CLONE_STOPPED flag was introduced in the 2.6.0-test1 series.  */
 347 #if __LINUX_KERNEL_VERSION >= 132609
 348 # define __ASSUME_CLONE_STOPPED 1
 349 #endif
 350 #endif
 351
 352 /* The fixed version of the posix_fadvise64 syscall appeared in
 353    2.6.0-test3.  At least for x86.  Powerpc support appeared in
 354    2.6.2, but for 32-bit userspace only.  */
 355 #if (__LINUX_KERNEL_VERSION >= 132609 && defined __i386__) \
 356     || (__LINUX_KERNEL_VERSION >= 132610 && defined __powerpc__ \
 357        && !defined __powerpc64__)
 358 # define __ASSUME_FADVISE64_64_SYSCALL  1
 359 #endif
 360
 361 /* The PROT_GROWSDOWN/PROT_GROWSUP flags were introduced in the 2.6.0-test
 362    series.  */
 363 #if __LINUX_KERNEL_VERSION >= 132609
 364 # define __ASSUME_PROT_GROWSUPDOWN      1
 365 #endif
 366
 367 /* Starting with 2.6.0 PowerPC adds signal/swapcontext support for Vector
 368    SIMD (AKA Altivec, VMX) instructions and register state.  This changes
 369    the overall size of the sigcontext and adds the swapcontext syscall.  */
 370 #if __LINUX_KERNEL_VERSION >= 132608 && defined __powerpc__
 371 # define __ASSUME_SWAPCONTEXT_SYSCALL   1
 372 #endif
 373
 374 /* The CLONE_DETACHED flag is not necessary in 2.6.2 kernels, it is
 375    implied.  */
 376 #if __LINUX_KERNEL_VERSION >= 132610
 377 # define __ASSUME_NO_CLONE_DETACHED     1
 378 #endif
 379
 380 /* Starting with version 2.6.4-rc1 the getdents syscall returns d_type
 381    information as well and in between 2.6.5 and 2.6.8 most compat wrappers
 382    were fixed too.  Except s390{,x} which was fixed in 2.6.11.  */
 383 #if (__LINUX_KERNEL_VERSION >= 0x020608 && !defined __s390__) \
 384     || (__LINUX_KERNEL_VERSION >= 0x02060b && defined __s390__)
 385 # define __ASSUME_GETDENTS32_D_TYPE     1
 386 #endif
 387
 388 /* Starting with version 2.5.3, the initial location returned by `brk'
 389    after exec is always rounded up to the next page.  */
 390 #if __LINUX_KERNEL_VERSION >= 132355
 391 # define __ASSUME_BRK_PAGE_ROUNDED      1
 392 #endif
 393
 394 /* Starting with version 2.6.9, the waitid system call is available.
 395    Except for powerpc{,64} and s390{,x}, where it is available in 2.6.12.  */
 396 #if (__LINUX_KERNEL_VERSION >= 0x020609 \
 397      && !defined __powerpc__ && !defined __s390__) \
 398     || (__LINUX_KERNEL_VERSION >= 0x02060c \
 399         && (defined __powerpc__ || defined __s390__))
 400 # define __ASSUME_WAITID_SYSCALL        1
 401 #endif
 402
 403 /* On sparc64 stat64/lstat64/fstat64 syscalls were introduced in 2.6.12.  */
 404 #if __LINUX_KERNEL_VERSION >= 0x02060c && defined __sparc__ \
 405     && defined __arch64__
 406 # define __ASSUME_STAT64_SYSCALL        1
 407 #endif
 408
 409 /* Early kernel used "shm" as the filesystem name for the filesystem used
 410    for shm_open etc.  Later it is "tmpfs".  2.4.20 is a safe bet for the
 411    cutover.  */
 412 #if __LINUX_KERNEL_VERSION >= 0x02041a
 413 # define __ASSUME_TMPFS_NAME    1
 414 #endif
 415
 416 /* pselect/ppoll were introduced just after 2.6.16-rc1.  Due to the way
 417    the kernel versions are advertised we can only rely on 2.6.17 to have
 418    the code.  On x86_64 and SH this appeared first in 2.6.19-rc1,
 419    on ia64 in 2.6.22-rc1.  */
 420 #if __LINUX_KERNEL_VERSION >= 0x020611 \
 421     && ((!defined __x86_64__ && !defined __sh__) \
 422         || (__LINUX_KERNEL_VERSION >= 0x020613 \
 423             && (defined __x86_64__ || defined __sh__)))
 424 # define __ASSUME_PSELECT       1
 425 # define __ASSUME_PPOLL         1
 426 #endif
 427
 428 /* The *at syscalls were introduced just after 2.6.16-rc1.  Due to the way the
 429    kernel versions are advertised we can only rely on 2.6.17 to have
 430    the code.  On PPC they were introduced in 2.6.17-rc1,
 431    on SH in 2.6.19-rc1.  */
 432 #if __LINUX_KERNEL_VERSION >= 0x020611 \
 433     && (!defined __sh__ || __LINUX_KERNEL_VERSION >= 0x020613)
 434 # define __ASSUME_ATFCTS        1
 435 #endif
 436
 437 /* Support for inter-process robust mutexes was added in 2.6.17.  */
 438 #if __LINUX_KERNEL_VERSION >= 0x020611 \
 439     && (!defined __sh__ || __LINUX_KERNEL_VERSION >= 0x020613)
 440 # define __ASSUME_SET_ROBUST_LIST       1
 441 #endif
 442
 443 /* Pessimistically assume that 2.6.18 introduced real handling of
 444    large numbers of requests to readv and writev and that we don't
 445    need a fallback.  It likely worked for much longer.  */
 446 #if __LINUX_KERNEL_VERSION >= 0x020612
 447 # define __ASSUME_COMPLETE_READV_WRITEV 1
 448 #endif
 449
 450 /* Support for PI futexes was added in 2.6.18.  */
 451 #if __LINUX_KERNEL_VERSION >= 0x020612
 452 # define __ASSUME_FUTEX_LOCK_PI 1
 453 #endif
 454
 455 /* Support for utimensat syscall was added in 2.6.22, on SH
 456    only after 2.6.22-rc1.  */
 457 #if __LINUX_KERNEL_VERSION >= 0x020616 \
 458     && (!defined __sh__ || __LINUX_KERNEL_VERSION >= 0x020617)
 459 # define __ASSUME_UTIMENSAT     1
 460 #endif
 461
 462 /* Support for private futexes was added in 2.6.22.  */
 463 #if __LINUX_KERNEL_VERSION >= 0x020616
 464 # define __ASSUME_PRIVATE_FUTEX 1
 465 #endif
 466
 467 /* Support for fallocate was added in 2.6.23, on s390
 468    only after 2.6.23-rc1.  */
 469 #if __LINUX_KERNEL_VERSION >= 0x020617 \
 470     && (!defined __s390__ || __LINUX_KERNEL_VERSION >= 0x020618)
 471 # define __ASSUME_FALLOCATE     1
 472 #endif
 473
 474 /* Support for various CLOEXEC and NONBLOCK flags was added for x86,
 475    x86-64, PPC, IA-64, SPARC< and S390 in 2.6.23.  */
 476 #if __LINUX_KERNEL_VERSION >= 0x020617 \
 477     && (defined __i386__ || defined __x86_64__ || defined __powerpc__ \
 478         || defined __sparc__ || defined __s390__)
 479 # define __ASSUME_O_CLOEXEC     1
 480 #endif
 481
 482 /* Support for ADJ_OFFSET_SS_READ was added in 2.6.24.  */
 483 #if __LINUX_KERNEL_VERSION >= 0x020618
 484 # define __ASSUME_ADJ_OFFSET_SS_READ    1
 485 #endif
 486
 487 /* Support for various CLOEXEC and NONBLOCK flags was added for x86,
 488    x86-64, PPC, IA-64, and SPARC in 2.6.27.  */
 489 #if __LINUX_KERNEL_VERSION >= 0x02061b \
 490     && (defined __i386__ || defined __x86_64__ || defined __powerpc__ \
 491         || defined __sparc__ || defined __s390__)
 492 # define __ASSUME_SOCK_CLOEXEC  1
 493 # define __ASSUME_IN_NONBLOCK   1
 494 # define __ASSUME_PIPE2         1
 495 # define __ASSUME_EVENTFD2      1
 496 # define __ASSUME_SIGNALFD4     1
 497 # define __ASSUME_DUP3          1
 498 #endif
 499
 500 /* Support for the accept4 syscall was added in 2.6.28.  */
 501 #if __LINUX_KERNEL_VERSION >= 0x02061c \
 502     && (defined __i386__ || defined __x86_64__ || defined __powerpc__ \
 503         || defined __sparc__ || defined __s390__)
 504 # define __ASSUME_ACCEPT4       1
 505 #endif
 506
 507 /* Support for the FUTEX_CLOCK_REALTIME flag was added in 2.6.29.  */
 508 #if __LINUX_KERNEL_VERSION >= 0x02061d
 509 # define __ASSUME_FUTEX_CLOCK_REALTIME  1
 510 #endif
 511
 512 /* Support for the AT_RANDOM auxiliary vector entry was added in 2.6.29.  */
 513 #if __LINUX_KERNEL_VERSION >= 0x02061d
 514 # define __ASSUME_AT_RANDOM     1
 515 #endif
 516
 517 /* Support for preadv and pwritev was added in 2.6.30.  */
 518 #if __LINUX_KERNEL_VERSION >= 0x02061e
 519 # define __ASSUME_PREADV        1
 520 # define __ASSUME_PWRITEV       1
 521 #endif
 522
 523 /* Support for F_GETOWN_EX was introduced in 2.6.32.  */
 524 #if __LINUX_KERNEL_VERSION >= 0x020620
 525 # define __ASSUME_F_GETOWN_EX   1
 526 #endif
 527
 528 /* Support for the recvmmsg syscall was added in 2.6.33.  */
 529 #if __LINUX_KERNEL_VERSION >= 0x020621
 530 # define __ASSUME_RECVMMSG      1
 531 #endif
 532
 533 /* statfs fills in f_flags since 2.6.36.  */
 534 #if __LINUX_KERNEL_VERSION >= 0x020624
 535 # define __ASSUME_STATFS_F_FLAGS        1
 536 #endif
 537
 538 /* prlimit64 is available in 2.6.36.  */
 539 #if __LINUX_KERNEL_VERSION >= 0x020624
 540 # define __ASSUME_PRLIMIT64     1
 541 #endif
 542
 543 /* sendmmsg is available in 2.6.39.  */
 544 #if __LINUX_KERNEL_VERSION >= 0x020627
 545 # define __ASSUME_SENDMMSG      1
 546 #endif
 547
 548 /* getcpu is a syscall for x86-64 since 3.1.  */
 549 #if defined __x86_64__ && __LINUX_KERNEL_VERSION >= 0x030100
 550 # define __ASSUME_GETCPU_SYSCALL        1
 551 #endif