mount.h (8939B) - Raw
1 #ifndef _LINUX_MOUNT_H 2 #define _LINUX_MOUNT_H 3 4 #include <linux/types.h> 5 6 /* 7 * These are the fs-independent mount-flags: up to 32 flags are supported 8 * 9 * Usage of these is restricted within the kernel to core mount(2) code and 10 * callers of sys_mount() only. Filesystems should be using the SB_* 11 * equivalent instead. 12 */ 13 #define MS_RDONLY 1 /* Mount read-only */ 14 #define MS_NOSUID 2 /* Ignore suid and sgid bits */ 15 #define MS_NODEV 4 /* Disallow access to device special files */ 16 #define MS_NOEXEC 8 /* Disallow program execution */ 17 #define MS_SYNCHRONOUS 16 /* Writes are synced at once */ 18 #define MS_REMOUNT 32 /* Alter flags of a mounted FS */ 19 #define MS_MANDLOCK 64 /* Allow mandatory locks on an FS */ 20 #define MS_DIRSYNC 128 /* Directory modifications are synchronous */ 21 #define MS_NOSYMFOLLOW 256 /* Do not follow symlinks */ 22 #define MS_NOATIME 1024 /* Do not update access times. */ 23 #define MS_NODIRATIME 2048 /* Do not update directory access times */ 24 #define MS_BIND 4096 25 #define MS_MOVE 8192 26 #define MS_REC 16384 27 #define MS_VERBOSE 32768 /* War is peace. Verbosity is silence. 28 MS_VERBOSE is deprecated. */ 29 #define MS_SILENT 32768 30 #define MS_POSIXACL (1<<16) /* VFS does not apply the umask */ 31 #define MS_UNBINDABLE (1<<17) /* change to unbindable */ 32 #define MS_PRIVATE (1<<18) /* change to private */ 33 #define MS_SLAVE (1<<19) /* change to slave */ 34 #define MS_SHARED (1<<20) /* change to shared */ 35 #define MS_RELATIME (1<<21) /* Update atime relative to mtime/ctime. */ 36 #define MS_KERNMOUNT (1<<22) /* this is a kern_mount call */ 37 #define MS_I_VERSION (1<<23) /* Update inode I_version field */ 38 #define MS_STRICTATIME (1<<24) /* Always perform atime updates */ 39 #define MS_LAZYTIME (1<<25) /* Update the on-disk [acm]times lazily */ 40 41 /* These sb flags are internal to the kernel */ 42 #define MS_SUBMOUNT (1<<26) 43 #define MS_NOREMOTELOCK (1<<27) 44 #define MS_NOSEC (1<<28) 45 #define MS_BORN (1<<29) 46 #define MS_ACTIVE (1<<30) 47 #define MS_NOUSER (1<<31) 48 49 /* 50 * Superblock flags that can be altered by MS_REMOUNT 51 */ 52 #define MS_RMT_MASK (MS_RDONLY|MS_SYNCHRONOUS|MS_MANDLOCK|MS_I_VERSION|\ 53 MS_LAZYTIME) 54 55 /* 56 * Old magic mount flag and mask 57 */ 58 #define MS_MGC_VAL 0xC0ED0000 59 #define MS_MGC_MSK 0xffff0000 60 61 /* 62 * open_tree() flags. 63 */ 64 #define OPEN_TREE_CLONE 1 /* Clone the target tree and attach the clone */ 65 #define OPEN_TREE_CLOEXEC O_CLOEXEC /* Close the file on execve() */ 66 67 /* 68 * move_mount() flags. 69 */ 70 #define MOVE_MOUNT_F_SYMLINKS 0x00000001 /* Follow symlinks on from path */ 71 #define MOVE_MOUNT_F_AUTOMOUNTS 0x00000002 /* Follow automounts on from path */ 72 #define MOVE_MOUNT_F_EMPTY_PATH 0x00000004 /* Empty from path permitted */ 73 #define MOVE_MOUNT_T_SYMLINKS 0x00000010 /* Follow symlinks on to path */ 74 #define MOVE_MOUNT_T_AUTOMOUNTS 0x00000020 /* Follow automounts on to path */ 75 #define MOVE_MOUNT_T_EMPTY_PATH 0x00000040 /* Empty to path permitted */ 76 #define MOVE_MOUNT_SET_GROUP 0x00000100 /* Set sharing group instead */ 77 #define MOVE_MOUNT_BENEATH 0x00000200 /* Mount beneath top mount */ 78 #define MOVE_MOUNT__MASK 0x00000377 79 80 /* 81 * fsopen() flags. 82 */ 83 #define FSOPEN_CLOEXEC 0x00000001 84 85 /* 86 * fspick() flags. 87 */ 88 #define FSPICK_CLOEXEC 0x00000001 89 #define FSPICK_SYMLINK_NOFOLLOW 0x00000002 90 #define FSPICK_NO_AUTOMOUNT 0x00000004 91 #define FSPICK_EMPTY_PATH 0x00000008 92 93 /* 94 * The type of fsconfig() call made. 95 */ 96 enum fsconfig_command { 97 FSCONFIG_SET_FLAG = 0, /* Set parameter, supplying no value */ 98 FSCONFIG_SET_STRING = 1, /* Set parameter, supplying a string value */ 99 FSCONFIG_SET_BINARY = 2, /* Set parameter, supplying a binary blob value */ 100 FSCONFIG_SET_PATH = 3, /* Set parameter, supplying an object by path */ 101 FSCONFIG_SET_PATH_EMPTY = 4, /* Set parameter, supplying an object by (empty) path */ 102 FSCONFIG_SET_FD = 5, /* Set parameter, supplying an object by fd */ 103 FSCONFIG_CMD_CREATE = 6, /* Create new or reuse existing superblock */ 104 FSCONFIG_CMD_RECONFIGURE = 7, /* Invoke superblock reconfiguration */ 105 FSCONFIG_CMD_CREATE_EXCL = 8, /* Create new superblock, fail if reusing existing superblock */ 106 }; 107 108 /* 109 * fsmount() flags. 110 */ 111 #define FSMOUNT_CLOEXEC 0x00000001 112 113 /* 114 * Mount attributes. 115 */ 116 #define MOUNT_ATTR_RDONLY 0x00000001 /* Mount read-only */ 117 #define MOUNT_ATTR_NOSUID 0x00000002 /* Ignore suid and sgid bits */ 118 #define MOUNT_ATTR_NODEV 0x00000004 /* Disallow access to device special files */ 119 #define MOUNT_ATTR_NOEXEC 0x00000008 /* Disallow program execution */ 120 #define MOUNT_ATTR__ATIME 0x00000070 /* Setting on how atime should be updated */ 121 #define MOUNT_ATTR_RELATIME 0x00000000 /* - Update atime relative to mtime/ctime. */ 122 #define MOUNT_ATTR_NOATIME 0x00000010 /* - Do not update access times. */ 123 #define MOUNT_ATTR_STRICTATIME 0x00000020 /* - Always perform atime updates */ 124 #define MOUNT_ATTR_NODIRATIME 0x00000080 /* Do not update directory access times */ 125 #define MOUNT_ATTR_IDMAP 0x00100000 /* Idmap mount to @userns_fd in struct mount_attr. */ 126 #define MOUNT_ATTR_NOSYMFOLLOW 0x00200000 /* Do not follow symlinks */ 127 128 /* 129 * mount_setattr() 130 */ 131 struct mount_attr { 132 __u64 attr_set; 133 __u64 attr_clr; 134 __u64 propagation; 135 __u64 userns_fd; 136 }; 137 138 /* List of all mount_attr versions. */ 139 #define MOUNT_ATTR_SIZE_VER0 32 /* sizeof first published struct */ 140 141 142 /* 143 * Structure for getting mount/superblock/filesystem info with statmount(2). 144 * 145 * The interface is similar to statx(2): individual fields or groups can be 146 * selected with the @mask argument of statmount(). Kernel will set the @mask 147 * field according to the supported fields. 148 * 149 * If string fields are selected, then the caller needs to pass a buffer that 150 * has space after the fixed part of the structure. Nul terminated strings are 151 * copied there and offsets relative to @str are stored in the relevant fields. 152 * If the buffer is too small, then EOVERFLOW is returned. The actually used 153 * size is returned in @size. 154 */ 155 struct statmount { 156 __u32 size; /* Total size, including strings */ 157 __u32 mnt_opts; /* [str] Options (comma separated, escaped) */ 158 __u64 mask; /* What results were written */ 159 __u32 sb_dev_major; /* Device ID */ 160 __u32 sb_dev_minor; 161 __u64 sb_magic; /* ..._SUPER_MAGIC */ 162 __u32 sb_flags; /* SB_{RDONLY,SYNCHRONOUS,DIRSYNC,LAZYTIME} */ 163 __u32 fs_type; /* [str] Filesystem type */ 164 __u64 mnt_id; /* Unique ID of mount */ 165 __u64 mnt_parent_id; /* Unique ID of parent (for root == mnt_id) */ 166 __u32 mnt_id_old; /* Reused IDs used in proc/.../mountinfo */ 167 __u32 mnt_parent_id_old; 168 __u64 mnt_attr; /* MOUNT_ATTR_... */ 169 __u64 mnt_propagation; /* MS_{SHARED,SLAVE,PRIVATE,UNBINDABLE} */ 170 __u64 mnt_peer_group; /* ID of shared peer group */ 171 __u64 mnt_master; /* Mount receives propagation from this ID */ 172 __u64 propagate_from; /* Propagation from in current namespace */ 173 __u32 mnt_root; /* [str] Root of mount relative to root of fs */ 174 __u32 mnt_point; /* [str] Mountpoint relative to current root */ 175 __u64 mnt_ns_id; /* ID of the mount namespace */ 176 __u32 fs_subtype; /* [str] Subtype of fs_type (if any) */ 177 __u32 sb_source; /* [str] Source string of the mount */ 178 __u32 opt_num; /* Number of fs options */ 179 __u32 opt_array; /* [str] Array of nul terminated fs options */ 180 __u32 opt_sec_num; /* Number of security options */ 181 __u32 opt_sec_array; /* [str] Array of nul terminated security options */ 182 __u64 __spare2[46]; 183 char str[]; /* Variable size part containing strings */ 184 }; 185 186 /* 187 * Structure for passing mount ID and miscellaneous parameters to statmount(2) 188 * and listmount(2). 189 * 190 * For statmount(2) @param represents the request mask. 191 * For listmount(2) @param represents the last listed mount id (or zero). 192 */ 193 struct mnt_id_req { 194 __u32 size; 195 __u32 spare; 196 __u64 mnt_id; 197 __u64 param; 198 __u64 mnt_ns_id; 199 }; 200 201 /* List of all mnt_id_req versions. */ 202 #define MNT_ID_REQ_SIZE_VER0 24 /* sizeof first published struct */ 203 #define MNT_ID_REQ_SIZE_VER1 32 /* sizeof second published struct */ 204 205 /* 206 * @mask bits for statmount(2) 207 */ 208 #define STATMOUNT_SB_BASIC 0x00000001U /* Want/got sb_... */ 209 #define STATMOUNT_MNT_BASIC 0x00000002U /* Want/got mnt_... */ 210 #define STATMOUNT_PROPAGATE_FROM 0x00000004U /* Want/got propagate_from */ 211 #define STATMOUNT_MNT_ROOT 0x00000008U /* Want/got mnt_root */ 212 #define STATMOUNT_MNT_POINT 0x00000010U /* Want/got mnt_point */ 213 #define STATMOUNT_FS_TYPE 0x00000020U /* Want/got fs_type */ 214 #define STATMOUNT_MNT_NS_ID 0x00000040U /* Want/got mnt_ns_id */ 215 #define STATMOUNT_MNT_OPTS 0x00000080U /* Want/got mnt_opts */ 216 #define STATMOUNT_FS_SUBTYPE 0x00000100U /* Want/got fs_subtype */ 217 #define STATMOUNT_SB_SOURCE 0x00000200U /* Want/got sb_source */ 218 #define STATMOUNT_OPT_ARRAY 0x00000400U /* Want/got opt_... */ 219 #define STATMOUNT_OPT_SEC_ARRAY 0x00000800U /* Want/got opt_sec... */ 220 221 /* 222 * Special @mnt_id values that can be passed to listmount 223 */ 224 #define LSMT_ROOT 0xffffffffffffffff /* root mount */ 225 #define LISTMOUNT_REVERSE (1 << 0) /* List later mounts first */ 226 227 #endif /* _LINUX_MOUNT_H */