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The C and C++ Include Header Files
cat -n /usr/include/x86_64-linux-gnu/sys/mount.h
1 /* Header file for mounting/unmount Linux filesystems. 2 Copyright (C) 1996-2026 Free Software Foundation, Inc. 3 This file is part of the GNU C Library. 4 5 The GNU C Library is free software; you can redistribute it and/or 6 modify it under the terms of the GNU Lesser General Public 7 License as published by the Free Software Foundation; either 8 version 2.1 of the License, or (at your option) any later version. 9 10 The GNU C Library is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public 16 License along with the GNU C Library; if not, see 17 <https://www.gnu.org/licenses/>. */ 18 19 /* This is taken from /usr/include/linux/fs.h. */ 20 21 #ifndef _SYS_MOUNT_H 22 #define _SYS_MOUNT_H 1 23 24 #include <fcntl.h> 25 #include <features.h> 26 #include <stdint.h> 27 #include <stddef.h> 28 #include <sys/ioctl.h> 29 30 #ifdef __has_include 31 # if __has_include ("linux/mount.h") 32 # include "linux/mount.h" 33 # endif 34 #endif 35 36 37 #define BLOCK_SIZE_BITS 10 38 #define BLOCK_SIZE (1<<BLOCK_SIZE_BITS) 39 40 41 /* These are the fs-independent mount-flags: up to 16 flags are 42 supported */ 43 enum 44 { 45 #undef MS_RDONLY 46 MS_RDONLY = 1, /* Mount read-only. */ 47 #define MS_RDONLY MS_RDONLY 48 #undef MS_NOSUID 49 MS_NOSUID = 2, /* Ignore suid and sgid bits. */ 50 #define MS_NOSUID MS_NOSUID 51 #undef MS_NODEV 52 MS_NODEV = 4, /* Disallow access to device special files. */ 53 #define MS_NODEV MS_NODEV 54 #undef MS_NOEXEC 55 MS_NOEXEC = 8, /* Disallow program execution. */ 56 #define MS_NOEXEC MS_NOEXEC 57 #undef MS_SYNCHRONOUS 58 MS_SYNCHRONOUS = 16, /* Writes are synced at once. */ 59 #define MS_SYNCHRONOUS MS_SYNCHRONOUS 60 #undef MS_REMOUNT 61 MS_REMOUNT = 32, /* Alter flags of a mounted FS. */ 62 #define MS_REMOUNT MS_REMOUNT 63 #undef MS_MANDLOCK 64 MS_MANDLOCK = 64, /* Allow mandatory locks on an FS. */ 65 #define MS_MANDLOCK MS_MANDLOCK 66 #undef MS_DIRSYNC 67 MS_DIRSYNC = 128, /* Directory modifications are synchronous. */ 68 #define MS_DIRSYNC MS_DIRSYNC 69 #undef MS_NOSYMFOLLOW 70 MS_NOSYMFOLLOW = 256, /* Do not follow symlinks. */ 71 #define MS_NOSYMFOLLOW MS_NOSYMFOLLOW 72 #undef MS_NOATIME 73 MS_NOATIME = 1024, /* Do not update access times. */ 74 #define MS_NOATIME MS_NOATIME 75 #undef MS_NODIRATIME 76 MS_NODIRATIME = 2048, /* Do not update directory access times. */ 77 #define MS_NODIRATIME MS_NODIRATIME 78 #undef MS_BIND 79 MS_BIND = 4096, /* Bind directory at different place. */ 80 #define MS_BIND MS_BIND 81 #undef MS_MOVE 82 MS_MOVE = 8192, 83 #define MS_MOVE MS_MOVE 84 #undef MS_REC 85 MS_REC = 16384, 86 #define MS_REC MS_REC 87 #undef MS_SILENT 88 MS_SILENT = 32768, 89 #define MS_SILENT MS_SILENT 90 #undef MS_POSIXACL 91 MS_POSIXACL = 1 << 16, /* VFS does not apply the umask. */ 92 #define MS_POSIXACL MS_POSIXACL 93 #undef MS_UNBINDABLE 94 MS_UNBINDABLE = 1 << 17, /* Change to unbindable. */ 95 #define MS_UNBINDABLE MS_UNBINDABLE 96 #undef MS_PRIVATE 97 MS_PRIVATE = 1 << 18, /* Change to private. */ 98 #define MS_PRIVATE MS_PRIVATE 99 #undef MS_SLAVE 100 MS_SLAVE = 1 << 19, /* Change to slave. */ 101 #define MS_SLAVE MS_SLAVE 102 #undef MS_SHARED 103 MS_SHARED = 1 << 20, /* Change to shared. */ 104 #define MS_SHARED MS_SHARED 105 #undef MS_RELATIME 106 MS_RELATIME = 1 << 21, /* Update atime relative to mtime/ctime. */ 107 #define MS_RELATIME MS_RELATIME 108 #undef MS_KERNMOUNT 109 MS_KERNMOUNT = 1 << 22, /* This is a kern_mount call. */ 110 #define MS_KERNMOUNT MS_KERNMOUNT 111 #undef MS_I_VERSION 112 MS_I_VERSION = 1 << 23, /* Update inode I_version field. */ 113 #define MS_I_VERSION MS_I_VERSION 114 #undef MS_STRICTATIME 115 MS_STRICTATIME = 1 << 24, /* Always perform atime updates. */ 116 #define MS_STRICTATIME MS_STRICTATIME 117 #undef MS_LAZYTIME 118 MS_LAZYTIME = 1 << 25, /* Update the on-disk [acm]times lazily. */ 119 #define MS_LAZYTIME MS_LAZYTIME 120 #undef MS_ACTIVE 121 MS_ACTIVE = 1 << 30, 122 #define MS_ACTIVE MS_ACTIVE 123 #undef MS_NOUSER 124 MS_NOUSER = 1U << 31 125 #define MS_NOUSER MS_NOUSER 126 }; 127 128 /* Flags that can be altered by MS_REMOUNT */ 129 #undef MS_RMT_MASK 130 #define MS_RMT_MASK (MS_RDONLY|MS_SYNCHRONOUS|MS_MANDLOCK|MS_I_VERSION \ 131 |MS_LAZYTIME) 132 133 134 /* Magic mount flag number. Has to be or-ed to the flag values. */ 135 136 #undef MS_MGC_VAL 137 #define MS_MGC_VAL 0xc0ed0000 /* Magic flag number to indicate "new" flags */ 138 #define MS_MGC_MSK 0xffff0000 /* Magic flag number mask */ 139 140 141 /* The read-only stuff doesn't really belong here, but any other place 142 is probably as bad and I don't want to create yet another include 143 file. */ 144 145 #undef BLKROSET 146 #define BLKROSET _IO(0x12, 93) /* Set device read-only (0 = read-write). */ 147 #undef BLKROGET 148 #define BLKROGET _IO(0x12, 94) /* Get read-only status (0 = read_write). */ 149 #undef BLKRRPART 150 #define BLKRRPART _IO(0x12, 95) /* Re-read partition table. */ 151 #undef BLKGETSIZE 152 #define BLKGETSIZE _IO(0x12, 96) /* Return device size. */ 153 #undef BLKFLSBUF 154 #define BLKFLSBUF _IO(0x12, 97) /* Flush buffer cache. */ 155 #undef BLKRASET 156 #define BLKRASET _IO(0x12, 98) /* Set read ahead for block device. */ 157 #undef BLKRAGET 158 #define BLKRAGET _IO(0x12, 99) /* Get current read ahead setting. */ 159 #undef BLKFRASET 160 #define BLKFRASET _IO(0x12,100) /* Set filesystem read-ahead. */ 161 #undef BLKFRAGET 162 #define BLKFRAGET _IO(0x12,101) /* Get filesystem read-ahead. */ 163 #undef BLKSECTSET 164 #define BLKSECTSET _IO(0x12,102) /* Set max sectors per request. */ 165 #undef BLKSECTGET 166 #define BLKSECTGET _IO(0x12,103) /* Get max sectors per request. */ 167 #undef BLKSSZGET 168 #define BLKSSZGET _IO(0x12,104) /* Get block device sector size. */ 169 #undef BLKBSZGET 170 #define BLKBSZGET _IOR(0x12,112,size_t) 171 #undef BLKBSZSET 172 #define BLKBSZSET _IOW(0x12,113,size_t) 173 #undef BLKGETSIZE64 174 #define BLKGETSIZE64 _IOR(0x12,114,size_t) /* return device size. */ 175 176 177 /* Possible value for FLAGS parameter of `umount2'. */ 178 enum 179 { 180 MNT_FORCE = 1, /* Force unmounting. */ 181 #define MNT_FORCE MNT_FORCE 182 MNT_DETACH = 2, /* Just detach from the tree. */ 183 #define MNT_DETACH MNT_DETACH 184 MNT_EXPIRE = 4, /* Mark for expiry. */ 185 #define MNT_EXPIRE MNT_EXPIRE 186 UMOUNT_NOFOLLOW = 8 /* Don't follow symlink on umount. */ 187 #define UMOUNT_NOFOLLOW UMOUNT_NOFOLLOW 188 }; 189 190 191 /* fsmount flags. */ 192 #define FSMOUNT_CLOEXEC 0x00000001 193 194 /* mount attributes used on fsmount. */ 195 #define MOUNT_ATTR_RDONLY 0x00000001 /* Mount read-only. */ 196 #define MOUNT_ATTR_NOSUID 0x00000002 /* Ignore suid and sgid bits. */ 197 #define MOUNT_ATTR_NODEV 0x00000004 /* Disallow access to device special files. */ 198 #define MOUNT_ATTR_NOEXEC 0x00000008 /* Disallow program execution. */ 199 #define MOUNT_ATTR__ATIME 0x00000070 /* Setting on how atime should be updated. */ 200 #define MOUNT_ATTR_RELATIME 0x00000000 /* - Update atime relative to mtime/ctime. */ 201 #define MOUNT_ATTR_NOATIME 0x00000010 /* - Do not update access times. */ 202 #define MOUNT_ATTR_STRICTATIME 0x00000020 /* - Always perform atime updates */ 203 #define MOUNT_ATTR_NODIRATIME 0x00000080 /* Do not update directory access times. */ 204 #define MOUNT_ATTR_IDMAP 0x00100000 /* Idmap mount to @userns_fd in struct mount_attr. */ 205 #define MOUNT_ATTR_NOSYMFOLLOW 0x00200000 /* Do not follow symlinks. */ 206 207 208 #ifndef MOUNT_ATTR_SIZE_VER0 209 /* For mount_setattr. */ 210 struct mount_attr 211 { 212 uint64_t attr_set; 213 uint64_t attr_clr; 214 uint64_t propagation; 215 uint64_t userns_fd; 216 }; 217 #endif 218 219 #define MOUNT_ATTR_SIZE_VER0 32 /* sizeof first published struct */ 220 221 /* move_mount flags. */ 222 #define MOVE_MOUNT_F_SYMLINKS 0x00000001 /* Follow symlinks on from path */ 223 #define MOVE_MOUNT_F_AUTOMOUNTS 0x00000002 /* Follow automounts on from path */ 224 #define MOVE_MOUNT_F_EMPTY_PATH 0x00000004 /* Empty from path permitted */ 225 #define MOVE_MOUNT_T_SYMLINKS 0x00000010 /* Follow symlinks on to path */ 226 #define MOVE_MOUNT_T_AUTOMOUNTS 0x00000020 /* Follow automounts on to path */ 227 #define MOVE_MOUNT_T_EMPTY_PATH 0x00000040 /* Empty to path permitted */ 228 #define MOVE_MOUNT_SET_GROUP 0x00000100 /* Set sharing group instead */ 229 #define MOVE_MOUNT_BENEATH 0x00000200 /* Mount beneath top mount */ 230 231 232 /* fspick flags. */ 233 #define FSPICK_CLOEXEC 0x00000001 234 #define FSPICK_SYMLINK_NOFOLLOW 0x00000002 235 #define FSPICK_NO_AUTOMOUNT 0x00000004 236 #define FSPICK_EMPTY_PATH 0x00000008 237 238 239 #ifndef FSOPEN_CLOEXEC 240 /* The type of fsconfig call made. */ 241 enum fsconfig_command 242 { 243 FSCONFIG_SET_FLAG = 0, /* Set parameter, supplying no value */ 244 # define FSCONFIG_SET_FLAG FSCONFIG_SET_FLAG 245 FSCONFIG_SET_STRING = 1, /* Set parameter, supplying a string value */ 246 # define FSCONFIG_SET_STRING FSCONFIG_SET_STRING 247 FSCONFIG_SET_BINARY = 2, /* Set parameter, supplying a binary blob value */ 248 # define FSCONFIG_SET_BINARY FSCONFIG_SET_BINARY 249 FSCONFIG_SET_PATH = 3, /* Set parameter, supplying an object by path */ 250 # define FSCONFIG_SET_PATH FSCONFIG_SET_PATH 251 FSCONFIG_SET_PATH_EMPTY = 4, /* Set parameter, supplying an object by (empty) path */ 252 # define FSCONFIG_SET_PATH_EMPTY FSCONFIG_SET_PATH_EMPTY 253 FSCONFIG_SET_FD = 5, /* Set parameter, supplying an object by fd */ 254 # define FSCONFIG_SET_FD FSCONFIG_SET_FD 255 FSCONFIG_CMD_CREATE = 6, /* Invoke superblock creation */ 256 # define FSCONFIG_CMD_CREATE FSCONFIG_CMD_CREATE 257 FSCONFIG_CMD_RECONFIGURE = 7, /* Invoke superblock reconfiguration */ 258 # define FSCONFIG_CMD_RECONFIGURE FSCONFIG_CMD_RECONFIGURE 259 FSCONFIG_CMD_CREATE_EXCL = 8, /* Create new superblock, fail if reusing existing superblock */ 260 # define FSCONFIG_CMD_CREATE_EXCL FSCONFIG_CMD_CREATE_EXCL 261 }; 262 #endif 263 264 /* fsopen flags. */ 265 #define FSOPEN_CLOEXEC 0x00000001 266 267 /* open_tree flags. */ 268 #ifndef OPEN_TREE_CLONE 269 # define OPEN_TREE_CLONE 1 /* Clone the target tree and attach the clone */ 270 #endif 271 #ifndef OPEN_TREE_CLOEXEC 272 # define OPEN_TREE_CLOEXEC O_CLOEXEC /* Close the file on execve() */ 273 #endif 274 275 276 __BEGIN_DECLS 277 278 /* Mount a filesystem. */ 279 extern int mount (const char *__special_file, const char *__dir, 280 const char *__fstype, unsigned long int __rwflag, 281 const void *__data) __THROW; 282 283 /* Unmount a filesystem. */ 284 extern int umount (const char *__special_file) __THROW; 285 286 /* Unmount a filesystem. Force unmounting if FLAGS is set to MNT_FORCE. */ 287 extern int umount2 (const char *__special_file, int __flags) __THROW; 288 289 /* Open the filesystem referenced by FS_NAME so it can be configured for 290 mouting. */ 291 extern int fsopen (const char *__fs_name, unsigned int __flags) __THROW; 292 293 /* Create a mount representation for the FD created by fsopen using 294 FLAGS with ATTR_FLAGS describing how the mount is to be performed. */ 295 extern int fsmount (int __fd, unsigned int __flags, 296 unsigned int __ms_flags) __THROW; 297 298 /* Add the mounted FROM_DFD referenced by FROM_PATHNAME filesystem returned 299 by fsmount in the hierarchy in the place TO_DFD reference by TO_PATHNAME 300 using FLAGS. */ 301 extern int move_mount (int __from_dfd, const char *__from_pathname, 302 int __to_dfd, const char *__to_pathname, 303 unsigned int flags) __THROW; 304 305 /* Set parameters and trigger CMD action on the FD context. KEY, VALUE, 306 and AUX are used depending ng of the CMD. */ 307 extern int fsconfig (int __fd, unsigned int __cmd, const char *__key, 308 const void *__value, int __aux) __THROW; 309 310 /* Equivalent of fopen for an existing mount point. */ 311 extern int fspick (int __dfd, const char *__path, unsigned int __flags) 312 __THROW; 313 314 /* Open the mount point FILENAME in directory DFD using FLAGS. */ 315 extern int open_tree (int __dfd, const char *__filename, unsigned int __flags) 316 __THROW; 317 318 /* Change the mount properties of the mount or an entire mount tree. If 319 PATH is a relative pathname, then it is interpreted relative to the 320 directory referred to by the file descriptor dirfd. Otherwise if DFD is 321 the special value AT_FDCWD then PATH is interpreted relative to the current 322 working directory of the calling process. */ 323 extern int mount_setattr (int __dfd, const char *__path, unsigned int __flags, 324 struct mount_attr *__uattr, size_t __usize) 325 __THROW; 326 327 __END_DECLS 328 329 #endif /* _SYS_MOUNT_H */
