man5/filesystems.5

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  24 .\" 2007-12-14 mtk Added Reiserfs, XFS, JFS.
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  26 .TH FILESYSTEMS 5 2018-04-30 "Linux" "Linux Programmer's Manual"
  27 .nh
  28 .SH NAME
  29 filesystems \- Linux filesystem types: ext, ext2, ext3, ext4, hpfs, iso9660,
  30 JFS, minix, msdos, ncpfs nfs, ntfs, proc, Reiserfs, smb, sysv, umsdos, vfat,
  31 XFS, xiafs,
  32 .SH DESCRIPTION
  33 When, as is customary, the
  34 .B proc
  35 filesystem is mounted on
  36 .IR /proc ,
  37 you can find in the file
  38 .I /proc/filesystems
  39 which filesystems your kernel currently supports;
  40 see
  41 .BR proc (5)
  42 for more details.
  43 There is also a legacy
  44 .BR sysfs (2)
  45 system call (whose availability is controlled by the
  46 .\" commit: 6af9f7bf3c399e0ab1eee048e13572c6d4e15fe9
  47 .B CONFIG_SYSFS_SYSCALL
  48 kernel build configuration option since Linux 3.15)
  49 that enables enumeration of the currently available filesystem types
  50 regardless of
  51 .I /proc
  52 availability and/or sanity.
  53 .PP
  54 If you need a currently unsupported filesystem, insert the corresponding
  55 module or recompile the kernel.
  56 .PP
  57 In order to use a filesystem, you have to
  58 .I mount
  59 it; see
  60 .BR mount (2)
  61 and
  62 .BR mount (8).
  63 .PP
  64 Below a short description of the available or historically available
  65 filesystems in the Linux kernel.
  66 See kernel documentation for a comprehensive
  67 description of all options and limitations.
  68 .TP 10
  69 .B ext
  70 is an elaborate extension of the
  71 .B minix
  72 filesystem.
  73 It has been completely superseded by the second version
  74 of the extended filesystem
  75 .RB ( ext2 )
  76 and has been removed from the kernel (in 2.1.21).
  77 .TP
  78 .B ext2
  79 is the high performance disk filesystem used by Linux for fixed disks
  80 as well as removable media.
  81 The second extended filesystem was designed as an extension of the
  82 extended filesystem
  83 .RB ( ext ).
  84 See
  85 .BR ext2 (5).
  86 .TP
  87 .B ext3
  88 is a journaling version of the
  89 .B ext2
  90 filesystem.
  91 It is easy to
  92 switch back and forth between
  93 .B ext2
  94 and
  95 .BR ext3 .
  96 See
  97 .BR ext3 (5).
  98 .TP
  99 .B ext4
 100 is a set of upgrades to
 101 .B ext3
 102 including substantial performance and
 103 reliability enhancements,
 104 plus large increases in volume, file, and directory size limits.
 105 See
 106 .BR ext4 (5).
 107 .TP
 108 .B hpfs
 109 is the High Performance Filesystem, used in OS/2.
 110 This filesystem is
 111 read-only under Linux due to the lack of available documentation.
 112 .TP
 113 .B iso9660
 114 is a CD-ROM filesystem type conforming to the ISO 9660 standard.
 115 .RS
 116 .TP
 117 .B "High Sierra"
 118 Linux supports High Sierra, the precursor to the ISO 9660 standard for
 119 CD-ROM filesystems.
 120 It is automatically recognized within the
 121 .B iso9660
 122 filesystem support under Linux.
 123 .TP
 124 .B "Rock Ridge"
 125 Linux also supports the System Use Sharing Protocol records specified
 126 by the Rock Ridge Interchange Protocol.
 127 They are used to further describe the files in the
 128 .B iso9660
 129 filesystem to a UNIX host, and provide information such as long
 130 filenames, UID/GID, POSIX permissions, and devices.
 131 It is automatically recognized within the
 132 .B iso9660
 133 filesystem support under Linux.
 134 .RE
 135 .TP
 136 .B JFS
 137 is a journaling filesystem, developed by IBM,
 138 that was integrated into Linux in kernel 2.4.24.
 139 .TP
 140 .B minix
 141 is the filesystem used in the Minix operating system, the first to run
 142 under Linux.
 143 It has a number of shortcomings, including a 64\ MB partition size
 144 limit, short filenames, and a single timestamp.
 145 It remains useful for floppies and RAM disks.
 146 .TP
 147 .B msdos
 148 is the filesystem used by DOS, Windows, and some OS/2 computers.
 149 .B msdos
 150 filenames can be no longer than 8 characters, followed by an
 151 optional period and 3 character extension.
 152 .TP
 153 .B ncpfs
 154 is a network filesystem that supports the NCP protocol, used by
 155 Novell NetWare.
 156 .IP
 157 To use
 158 .BR ncpfs ,
 159 you need special programs, which can be found at
 160 .UR ftp://linux01.gwdg.de\:/pub\:/ncpfs
 161 .UE .
 162 .TP
 163 .B nfs
 164 is the network filesystem used to access disks located on remote computers.
 165 .TP
 166 .B ntfs
 167 replaces Microsoft Window's FAT filesystems (VFAT, FAT32).
 168 It has reliability, performance, and space-utilization enhancements
 169 plus features like ACLs, journaling, encryption, and so on.
 170 .TP
 171 .B proc
 172 is a pseudo filesystem which is used as an interface to kernel data
 173 structures rather than reading and interpreting
 174 .IR /dev/kmem .
 175 In particular, its files do not take disk space.
 176 See
 177 .BR proc (5).
 178 .TP
 179 .B Reiserfs
 180 is a journaling filesystem, designed by Hans Reiser,
 181 that was integrated into Linux in kernel 2.4.1.
 182 .TP
 183 .B smb
 184 is a network filesystem that supports the SMB protocol, used by
 185 Windows for Workgroups, Windows NT, and Lan Manager.
 186 See
 187 .UR https://www.samba.org\:/samba\:/smbfs/
 188 .UE .
 189 .TP
 190 .B sysv
 191 is an implementation of the SystemV/Coherent filesystem for Linux.
 192 It implements all of Xenix FS, SystemV/386 FS, and Coherent FS.
 193 .TP
 194 .B umsdos
 195 is an extended DOS filesystem used by Linux.
 196 It adds capability for
 197 long filenames, UID/GID, POSIX permissions, and special files
 198 (devices, named pipes, etc.) under the DOS filesystem, without
 199 sacrificing compatibility with DOS.
 200 .TP
 201 .B tmpfs
 202 is a filesystem whose contents reside in virtual memory.
 203 Since the files on such filesystems typically reside in RAM,
 204 file access is extremely fast.
 205 See
 206 .BR tmpfs (5).
 207 .TP
 208 .B vfat
 209 is an extended FAT filesystem used by Microsoft Windows95 and Windows NT.
 210 .B vfat
 211 adds the capability to use long filenames under the MSDOS filesystem.
 212 .TP
 213 .B XFS
 214 is a journaling filesystem, developed by SGI,
 215 that was integrated into Linux in kernel 2.4.20.
 216 .TP
 217 .B xiafs
 218 was designed and implemented to be a stable, safe filesystem by
 219 extending the Minix filesystem code.
 220 It provides the basic most
 221 requested features without undue complexity.
 222 The
 223 .B xiafs
 224 filesystem is no longer actively developed or maintained.
 225 It was removed from the kernel in 2.1.21.
 226 .SH SEE ALSO
 227 .BR fuse (4),
 228 .BR btrfs (5),
 229 .BR ext2 (5),
 230 .BR ext3 (5),
 231 .BR ext4 (5),
 232 .BR nfs (5),
 233 .BR proc (5),
 234 .BR tmpfs (5),
 235 .BR fsck (8),
 236 .BR mkfs (8),
 237 .BR mount (8)