sysdeps/unix/sysv/linux/sys/mount.h

   1 /* Header file for mounting/unmount Linux filesystems.
   2    Copyright (C) 1996-2022 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 <features.h>
  25 #include <sys/ioctl.h>
  26
  27 #define BLOCK_SIZE      1024
  28 #define BLOCK_SIZE_BITS 10
  29
  30
  31 /* These are the fs-independent mount-flags: up to 16 flags are
  32    supported  */
  33 enum
  34 {
  35   MS_RDONLY = 1,                /* Mount read-only.  */
  36 #define MS_RDONLY       MS_RDONLY
  37   MS_NOSUID = 2,                /* Ignore suid and sgid bits.  */
  38 #define MS_NOSUID       MS_NOSUID
  39   MS_NODEV = 4,                 /* Disallow access to device special files.  */
  40 #define MS_NODEV        MS_NODEV
  41   MS_NOEXEC = 8,                /* Disallow program execution.  */
  42 #define MS_NOEXEC       MS_NOEXEC
  43   MS_SYNCHRONOUS = 16,          /* Writes are synced at once.  */
  44 #define MS_SYNCHRONOUS  MS_SYNCHRONOUS
  45   MS_REMOUNT = 32,              /* Alter flags of a mounted FS.  */
  46 #define MS_REMOUNT      MS_REMOUNT
  47   MS_MANDLOCK = 64,             /* Allow mandatory locks on an FS.  */
  48 #define MS_MANDLOCK     MS_MANDLOCK
  49   MS_DIRSYNC = 128,             /* Directory modifications are synchronous.  */
  50 #define MS_DIRSYNC      MS_DIRSYNC
  51   MS_NOSYMFOLLOW = 256,         /* Do not follow symlinks.  */
  52 #define MS_NOSYMFOLLOW  MS_NOSYMFOLLOW
  53   MS_NOATIME = 1024,            /* Do not update access times.  */
  54 #define MS_NOATIME      MS_NOATIME
  55   MS_NODIRATIME = 2048,         /* Do not update directory access times.  */
  56 #define MS_NODIRATIME   MS_NODIRATIME
  57   MS_BIND = 4096,               /* Bind directory at different place.  */
  58 #define MS_BIND         MS_BIND
  59   MS_MOVE = 8192,
  60 #define MS_MOVE         MS_MOVE
  61   MS_REC = 16384,
  62 #define MS_REC          MS_REC
  63   MS_SILENT = 32768,
  64 #define MS_SILENT       MS_SILENT
  65   MS_POSIXACL = 1 << 16,        /* VFS does not apply the umask.  */
  66 #define MS_POSIXACL     MS_POSIXACL
  67   MS_UNBINDABLE = 1 << 17,      /* Change to unbindable.  */
  68 #define MS_UNBINDABLE   MS_UNBINDABLE
  69   MS_PRIVATE = 1 << 18,         /* Change to private.  */
  70 #define MS_PRIVATE      MS_PRIVATE
  71   MS_SLAVE = 1 << 19,           /* Change to slave.  */
  72 #define MS_SLAVE        MS_SLAVE
  73   MS_SHARED = 1 << 20,          /* Change to shared.  */
  74 #define MS_SHARED       MS_SHARED
  75   MS_RELATIME = 1 << 21,        /* Update atime relative to mtime/ctime.  */
  76 #define MS_RELATIME     MS_RELATIME
  77   MS_KERNMOUNT = 1 << 22,       /* This is a kern_mount call.  */
  78 #define MS_KERNMOUNT    MS_KERNMOUNT
  79   MS_I_VERSION =  1 << 23,      /* Update inode I_version field.  */
  80 #define MS_I_VERSION    MS_I_VERSION
  81   MS_STRICTATIME = 1 << 24,     /* Always perform atime updates.  */
  82 #define MS_STRICTATIME  MS_STRICTATIME
  83   MS_LAZYTIME = 1 << 25,        /* Update the on-disk [acm]times lazily.  */
  84 #define MS_LAZYTIME     MS_LAZYTIME
  85   MS_ACTIVE = 1 << 30,
  86 #define MS_ACTIVE       MS_ACTIVE
  87   MS_NOUSER = 1 << 31
  88 #define MS_NOUSER       MS_NOUSER
  89 };
  90
  91 /* Flags that can be altered by MS_REMOUNT  */
  92 #define MS_RMT_MASK (MS_RDONLY|MS_SYNCHRONOUS|MS_MANDLOCK|MS_I_VERSION \
  93                      |MS_LAZYTIME)
  94
  95
  96 /* Magic mount flag number. Has to be or-ed to the flag values.  */
  97
  98 #define MS_MGC_VAL 0xc0ed0000   /* Magic flag number to indicate "new" flags */
  99 #define MS_MGC_MSK 0xffff0000   /* Magic flag number mask */
 100
 101
 102 /* The read-only stuff doesn't really belong here, but any other place
 103    is probably as bad and I don't want to create yet another include
 104    file.  */
 105
 106 #define BLKROSET   _IO(0x12, 93) /* Set device read-only (0 = read-write).  */
 107 #define BLKROGET   _IO(0x12, 94) /* Get read-only status (0 = read_write).  */
 108 #define BLKRRPART  _IO(0x12, 95) /* Re-read partition table.  */
 109 #define BLKGETSIZE _IO(0x12, 96) /* Return device size.  */
 110 #define BLKFLSBUF  _IO(0x12, 97) /* Flush buffer cache.  */
 111 #define BLKRASET   _IO(0x12, 98) /* Set read ahead for block device.  */
 112 #define BLKRAGET   _IO(0x12, 99) /* Get current read ahead setting.  */
 113 #define BLKFRASET  _IO(0x12,100) /* Set filesystem read-ahead.  */
 114 #define BLKFRAGET  _IO(0x12,101) /* Get filesystem read-ahead.  */
 115 #define BLKSECTSET _IO(0x12,102) /* Set max sectors per request.  */
 116 #define BLKSECTGET _IO(0x12,103) /* Get max sectors per request.  */
 117 #define BLKSSZGET  _IO(0x12,104) /* Get block device sector size.  */
 118 #define BLKBSZGET  _IOR(0x12,112,size_t)
 119 #define BLKBSZSET  _IOW(0x12,113,size_t)
 120 #define BLKGETSIZE64 _IOR(0x12,114,size_t) /* return device size.  */
 121
 122
 123 /* Possible value for FLAGS parameter of `umount2'.  */
 124 enum
 125 {
 126   MNT_FORCE = 1,                /* Force unmounting.  */
 127 #define MNT_FORCE MNT_FORCE
 128   MNT_DETACH = 2,               /* Just detach from the tree.  */
 129 #define MNT_DETACH MNT_DETACH
 130   MNT_EXPIRE = 4,               /* Mark for expiry.  */
 131 #define MNT_EXPIRE MNT_EXPIRE
 132   UMOUNT_NOFOLLOW = 8           /* Don't follow symlink on umount.  */
 133 #define UMOUNT_NOFOLLOW UMOUNT_NOFOLLOW
 134 };
 135
 136
 137 /* fsopen flags.  */
 138 #define FSOPEN_CLOEXEC          0x00000001
 139
 140 /* fsmount flags.  */
 141 #define FSMOUNT_CLOEXEC         0x00000001
 142
 143 /* mount attributes used on fsmount.  */
 144 #define MOUNT_ATTR_RDONLY       0x00000001 /* Mount read-only.  */
 145 #define MOUNT_ATTR_NOSUID       0x00000002 /* Ignore suid and sgid bits.  */
 146 #define MOUNT_ATTR_NODEV        0x00000004 /* Disallow access to device special files.  */
 147 #define MOUNT_ATTR_NOEXEC       0x00000008 /* Disallow program execution.  */
 148 #define MOUNT_ATTR__ATIME       0x00000070 /* Setting on how atime should be updated.  */
 149 #define MOUNT_ATTR_RELATIME     0x00000000 /* - Update atime relative to mtime/ctime.  */
 150 #define MOUNT_ATTR_NOATIME      0x00000010 /* - Do not update access times.  */
 151 #define MOUNT_ATTR_STRICTATIME  0x00000020 /* - Always perform atime updates  */
 152 #define MOUNT_ATTR_NODIRATIME   0x00000080 /* Do not update directory access times.  */
 153 #define MOUNT_ATTR_IDMAP        0x00100000 /* Idmap mount to @userns_fd in struct mount_attr.  */
 154 #define MOUNT_ATTR_NOSYMFOLLOW  0x00200000 /* Do not follow symlinks.  */
 155
 156
 157 /* move_mount flags.  */
 158 #define MOVE_MOUNT_F_SYMLINKS   0x00000001 /* Follow symlinks on from path */
 159 #define MOVE_MOUNT_F_AUTOMOUNTS 0x00000002 /* Follow automounts on from path */
 160 #define MOVE_MOUNT_F_EMPTY_PATH 0x00000004 /* Empty from path permitted */
 161 #define MOVE_MOUNT_T_SYMLINKS   0x00000010 /* Follow symlinks on to path */
 162 #define MOVE_MOUNT_T_AUTOMOUNTS 0x00000020 /* Follow automounts on to path */
 163 #define MOVE_MOUNT_T_EMPTY_PATH 0x00000040 /* Empty to path permitted */
 164 #define MOVE_MOUNT_SET_GROUP    0x00000100 /* Set sharing group instead */
 165
 166 /* The type of fsconfig call made.   */
 167 enum fsconfig_command
 168 {
 169   FSCONFIG_SET_FLAG       = 0,    /* Set parameter, supplying no value */
 170 #define FSCONFIG_SET_FLAG FSCONFIG_SET_FLAG
 171   FSCONFIG_SET_STRING     = 1,    /* Set parameter, supplying a string value */
 172 #define FSCONFIG_SET_STRING FSCONFIG_SET_STRING
 173   FSCONFIG_SET_BINARY     = 2,    /* Set parameter, supplying a binary blob value */
 174 #define FSCONFIG_SET_BINARY FSCONFIG_SET_BINARY
 175   FSCONFIG_SET_PATH       = 3,    /* Set parameter, supplying an object by path */
 176 #define FSCONFIG_SET_PATH FSCONFIG_SET_PATH
 177   FSCONFIG_SET_PATH_EMPTY = 4,    /* Set parameter, supplying an object by (empty) path */
 178 #define FSCONFIG_SET_PATH_EMPTY FSCONFIG_SET_PATH_EMPTY
 179   FSCONFIG_SET_FD         = 5,    /* Set parameter, supplying an object by fd */
 180 #define FSCONFIG_SET_FD FSCONFIG_SET_FD
 181   FSCONFIG_CMD_CREATE     = 6,    /* Invoke superblock creation */
 182 #define FSCONFIG_CMD_CREATE FSCONFIG_CMD_CREATE
 183   FSCONFIG_CMD_RECONFIGURE = 7,   /* Invoke superblock reconfiguration */
 184 #define FSCONFIG_CMD_RECONFIGURE FSCONFIG_CMD_RECONFIGURE
 185 };
 186
 187
 188 __BEGIN_DECLS
 189
 190 /* Mount a filesystem.  */
 191 extern int mount (const char *__special_file, const char *__dir,
 192                   const char *__fstype, unsigned long int __rwflag,
 193                   const void *__data) __THROW;
 194
 195 /* Unmount a filesystem.  */
 196 extern int umount (const char *__special_file) __THROW;
 197
 198 /* Unmount a filesystem.  Force unmounting if FLAGS is set to MNT_FORCE.  */
 199 extern int umount2 (const char *__special_file, int __flags) __THROW;
 200
 201 /* Open the filesystem referenced by FS_NAME so it can be configured for
 202    mouting.  */
 203 extern int fsopen (const char *__fs_name, unsigned int __flags) __THROW;
 204
 205 /* Create a mount representation for the FD created by fsopen using
 206    FLAGS with ATTR_FLAGS describing how the mount is to be performed.  */
 207 extern int fsmount (int __fd, unsigned int __flags,
 208                     unsigned int __ms_flags) __THROW;
 209
 210 /* Add the mounted FROM_DFD referenced by FROM_PATHNAME filesystem returned
 211    by fsmount in the hierarchy in the place TO_DFD reference by TO_PATHNAME
 212    using FLAGS.  */
 213 extern int move_mount (int __from_dfd, const char *__from_pathname,
 214                        int __to_dfd, const char *__to_pathname,
 215                        unsigned int flags) __THROW;
 216
 217 /* Set parameters and trigger CMD action on the FD context.  KEY, VALUE,
 218    and AUX are used depending ng of the CMD.  */
 219 extern int fsconfig (int __fd, unsigned int __cmd, const char *__key,
 220                      const void *__value, int __aux) __THROW;
 221
 222 __END_DECLS
 223
 224 #endif /* _SYS_MOUNT_H */