1 | /* Set flags signalling availability of kernel features based on given |
2 | kernel version number. |
3 | Copyright (C) 1999-2019 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 statfs64 syscalls are available in 2.5.74 (but not for alpha). */ |
41 | #define __ASSUME_STATFS64 1 |
42 | |
43 | /* pselect/ppoll were introduced just after 2.6.16-rc1. On x86_64 and |
44 | SH this appeared first in 2.6.19-rc1, on ia64 in 2.6.22-rc1. */ |
45 | #define __ASSUME_PSELECT 1 |
46 | |
47 | /* The *at syscalls were introduced just after 2.6.16-rc1. On PPC |
48 | they were introduced in 2.6.17-rc1, on SH in 2.6.19-rc1. */ |
49 | #define __ASSUME_ATFCTS 1 |
50 | |
51 | /* Support for inter-process robust mutexes was added in 2.6.17 (but |
52 | some architectures lack futex_atomic_cmpxchg_inatomic in some |
53 | configurations). */ |
54 | #define __ASSUME_SET_ROBUST_LIST 1 |
55 | |
56 | /* Support for various CLOEXEC and NONBLOCK flags was added in |
57 | 2.6.27. */ |
58 | #define __ASSUME_IN_NONBLOCK 1 |
59 | |
60 | /* Support for preadv and pwritev was added in 2.6.30. */ |
61 | #define __ASSUME_PREADV 1 |
62 | #define __ASSUME_PWRITEV 1 |
63 | |
64 | /* Support for sendmmsg functionality was added in 3.0. */ |
65 | #define __ASSUME_SENDMMSG 1 |
66 | |
67 | /* On most architectures, most socket syscalls are supported for all |
68 | supported kernel versions, but on some socketcall architectures |
69 | separate syscalls were only added later. */ |
70 | #define __ASSUME_SENDMSG_SYSCALL 1 |
71 | #define __ASSUME_RECVMSG_SYSCALL 1 |
72 | #define __ASSUME_ACCEPT_SYSCALL 1 |
73 | #define __ASSUME_CONNECT_SYSCALL 1 |
74 | #define __ASSUME_RECVFROM_SYSCALL 1 |
75 | #define __ASSUME_SENDTO_SYSCALL 1 |
76 | #define __ASSUME_ACCEPT4_SYSCALL 1 |
77 | #define __ASSUME_RECVMMSG_SYSCALL 1 |
78 | #define __ASSUME_SENDMMSG_SYSCALL 1 |
79 | |
80 | /* Support for SysV IPC through wired syscalls. All supported architectures |
81 | either support ipc syscall and/or all the ipc correspondent syscalls. */ |
82 | #define __ASSUME_DIRECT_SYSVIPC_SYSCALLS 1 |
83 | |
84 | /* Support for p{read,write}v2 was added in 4.6. However Linux default |
85 | implementation does not assume the __ASSUME_* and instead use a fallback |
86 | implementation based on p{read,write}v and returning an error for |
87 | non supported flags. */ |
88 | |
89 | /* Support for the renameat2 system call was added in kernel 3.15. */ |
90 | #if __LINUX_KERNEL_VERSION >= 0x030F00 |
91 | # define __ASSUME_RENAMEAT2 |
92 | #endif |
93 | |
94 | /* Support for the execveat syscall was added in 3.19. */ |
95 | #if __LINUX_KERNEL_VERSION >= 0x031300 |
96 | # define __ASSUME_EXECVEAT 1 |
97 | #endif |
98 | |
99 | #if __LINUX_KERNEL_VERSION >= 0x040400 |
100 | # define __ASSUME_MLOCK2 1 |
101 | #endif |
102 | |
103 | /* Support for statx was added in kernel 4.11. */ |
104 | #if __LINUX_KERNEL_VERSION >= 0x040B00 |
105 | # define __ASSUME_STATX 1 |
106 | #endif |
107 | |
108 | /* Support for clone call used on fork. The signature varies across the |
109 | architectures with current 4 different variants: |
110 | |
111 | 1. long int clone (unsigned long flags, unsigned long newsp, |
112 | int *parent_tidptr, unsigned long tls, |
113 | int *child_tidptr) |
114 | |
115 | 2. long int clone (unsigned long newsp, unsigned long clone_flags, |
116 | int *parent_tidptr, int * child_tidptr, |
117 | unsigned long tls) |
118 | |
119 | 3. long int clone (unsigned long flags, unsigned long newsp, |
120 | int stack_size, int *parent_tidptr, |
121 | int *child_tidptr, unsigned long tls) |
122 | |
123 | 4. long int clone (unsigned long flags, unsigned long newsp, |
124 | int *parent_tidptr, int *child_tidptr, |
125 | unsigned long tls) |
126 | |
127 | The fourth variant is intended to be used as the default for newer ports, |
128 | Also IA64 uses the third variant but with __NR_clone2 instead of |
129 | __NR_clone. |
130 | |
131 | The macros names to define the variant used for the architecture is |
132 | similar to kernel: |
133 | |
134 | - __ASSUME_CLONE_BACKWARDS: for variant 1. |
135 | - __ASSUME_CLONE_BACKWARDS2: for variant 2 (s390). |
136 | - __ASSUME_CLONE_BACKWARDS3: for variant 3 (microblaze). |
137 | - __ASSUME_CLONE_DEFAULT: for variant 4. |
138 | - __ASSUME_CLONE2: for clone2 with variant 3 (ia64). |
139 | */ |
140 | |
141 | #define __ASSUME_CLONE_DEFAULT 1 |
142 | |