1/* Set flags signalling availability of kernel features based on given
2 kernel version number.
3 Copyright (C) 1999-2016 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/* Some architectures use the socketcall multiplexer for some or all
44 socket-related operations instead of separate syscalls.
45 __ASSUME_SOCKETCALL is defined for such architectures. */
46
47/* The changed st_ino field appeared in 2.4.0-test6. However, SH is lame,
48 and still does not have a 64-bit inode field. */
49#define __ASSUME_ST_INO_64_BIT 1
50
51/* The getdents64 syscall was introduced in 2.4.0-test7 (but later for
52 MIPS n32). */
53#define __ASSUME_GETDENTS64_SYSCALL 1
54
55/* The statfs64 syscalls are available in 2.5.74 (but not for alpha). */
56#define __ASSUME_STATFS64 1
57
58/* pselect/ppoll were introduced just after 2.6.16-rc1. On x86_64 and
59 SH this appeared first in 2.6.19-rc1, on ia64 in 2.6.22-rc1. */
60#define __ASSUME_PSELECT 1
61#define __ASSUME_PPOLL 1
62
63/* The *at syscalls were introduced just after 2.6.16-rc1. On PPC
64 they were introduced in 2.6.17-rc1, on SH in 2.6.19-rc1. */
65#define __ASSUME_ATFCTS 1
66
67/* Support for inter-process robust mutexes was added in 2.6.17 (but
68 some architectures lack futex_atomic_cmpxchg_inatomic in some
69 configurations). */
70#define __ASSUME_SET_ROBUST_LIST 1
71
72/* Support for PI futexes was added in 2.6.18 (but some architectures
73 lack futex_atomic_cmpxchg_inatomic in some configurations). */
74#define __ASSUME_FUTEX_LOCK_PI 1
75
76/* Support for private futexes was added in 2.6.22. */
77#define __ASSUME_PRIVATE_FUTEX 1
78
79/* Support for fallocate was added in 2.6.23, on s390
80 only after 2.6.23-rc1. */
81#define __ASSUME_FALLOCATE 1
82
83/* Support for various CLOEXEC and NONBLOCK flags was added in
84 2.6.23. */
85#define __ASSUME_O_CLOEXEC 1
86
87/* Support for various CLOEXEC and NONBLOCK flags was added in
88 2.6.27. */
89#define __ASSUME_IN_NONBLOCK 1
90#define __ASSUME_PIPE2 1
91#define __ASSUME_EVENTFD2 1
92#define __ASSUME_SIGNALFD4 1
93#define __ASSUME_DUP3 1
94
95/* Support for accept4 functionality was added in 2.6.28, but for some
96 architectures using a separate syscall rather than socketcall that
97 syscall was only added later, and some architectures first had
98 socketcall support then a separate syscall. Define
99 __ASSUME_ACCEPT4_SOCKETCALL if glibc uses socketcall on this
100 architecture and accept4 is available through socketcall,
101 __ASSUME_ACCEPT4_SYSCALL if it is available through a separate
102 syscall, __ASSUME_ACCEPT4_SYSCALL_WITH_SOCKETCALL if it became
103 available through a separate syscall at the same time as through
104 socketcall, and __ASSUME_ACCEPT4 if the accept4 function is known
105 to work. */
106#ifdef __ASSUME_SOCKETCALL
107# define __ASSUME_ACCEPT4_SOCKETCALL 1
108#endif
109
110#if defined __ASSUME_ACCEPT4_SOCKETCALL || defined __ASSUME_ACCEPT4_SYSCALL
111# define __ASSUME_ACCEPT4 1
112#endif
113
114/* Support for the FUTEX_CLOCK_REALTIME flag was added in 2.6.29. */
115#define __ASSUME_FUTEX_CLOCK_REALTIME 1
116
117/* Support for preadv and pwritev was added in 2.6.30. */
118#define __ASSUME_PREADV 1
119#define __ASSUME_PWRITEV 1
120
121/* Support for FUTEX_*_REQUEUE_PI was added in 2.6.31 (but some
122 architectures lack futex_atomic_cmpxchg_inatomic in some
123 configurations). */
124#define __ASSUME_REQUEUE_PI 1
125
126/* Support for recvmmsg functionality was added in 2.6.33. The macros
127 defined correspond to those for accept4. */
128#if __LINUX_KERNEL_VERSION >= 0x020621 && defined __ASSUME_SOCKETCALL
129# define __ASSUME_RECVMMSG_SOCKETCALL 1
130#endif
131
132#if defined __ASSUME_RECVMMSG_SOCKETCALL || defined __ASSUME_RECVMMSG_SYSCALL
133# define __ASSUME_RECVMMSG 1
134#endif
135
136/* Support for /proc/self/task/$tid/comm and /proc/$pid/task/$tid/comm was
137 added in 2.6.33. */
138#if __LINUX_KERNEL_VERSION >= 0x020621
139# define __ASSUME_PROC_PID_TASK_COMM 1
140#endif
141
142/* statfs fills in f_flags since 2.6.36. */
143#if __LINUX_KERNEL_VERSION >= 0x020624
144# define __ASSUME_STATFS_F_FLAGS 1
145#endif
146
147/* prlimit64 is available in 2.6.36. */
148#if __LINUX_KERNEL_VERSION >= 0x020624
149# define __ASSUME_PRLIMIT64 1
150#endif
151
152/* Support for sendmmsg functionality was added in 3.0. The macros
153 defined correspond to those for accept4 and recvmmsg. */
154#if __LINUX_KERNEL_VERSION >= 0x030000 && defined __ASSUME_SOCKETCALL
155# define __ASSUME_SENDMMSG_SOCKETCALL 1
156#endif
157
158#if defined __ASSUME_SENDMMSG_SOCKETCALL || defined __ASSUME_SENDMMSG_SYSCALL
159# define __ASSUME_SENDMMSG 1
160#endif
161