blob: f9489ddbb76759d4dee11541434132e70a9b59fb [file] [log] [blame]
Mauro Carvalho Chehabc9817ad2020-02-17 17:12:29 +01001.. SPDX-License-Identifier: GPL-2.0
2
3===============
4UDF file system
5===============
Linus Torvalds1da177e2005-04-16 15:20:36 -07006
7If you encounter problems with reading UDF discs using this driver,
Jan Kara503c3112017-10-16 11:55:52 +02008please report them according to MAINTAINERS file.
Linus Torvalds1da177e2005-04-16 15:20:36 -07009
Phillip Susi55aa6012006-11-16 01:19:23 -080010Write support requires a block driver which supports writing. Currently
11dvd+rw drives and media support true random sector writes, and so a udf
12filesystem on such devices can be directly mounted read/write. CD-RW
13media however, does not support this. Instead the media can be formatted
14for packet mode using the utility cdrwtool, then the pktcdvd driver can
15be bound to the underlying cd device to provide the required buffering
16and read-modify-write cycles to allow the filesystem random sector writes
17while providing the hardware with only full packet writes. While not
18required for dvd+rw media, use of the pktcdvd driver often enhances
19performance due to very poor read-modify-write support supplied internally
20by drive firmware.
Linus Torvalds1da177e2005-04-16 15:20:36 -070021
22-------------------------------------------------------------------------------
Mauro Carvalho Chehabc9817ad2020-02-17 17:12:29 +010023
Linus Torvalds1da177e2005-04-16 15:20:36 -070024The following mount options are supported:
25
Mauro Carvalho Chehabc9817ad2020-02-17 17:12:29 +010026 =========== ======================================
Linus Torvalds1da177e2005-04-16 15:20:36 -070027 gid= Set the default group.
28 umask= Set the default umask.
Marcin Slusarz7ac9bcd52008-11-16 20:52:19 +010029 mode= Set the default file permissions.
30 dmode= Set the default directory permissions.
Linus Torvalds1da177e2005-04-16 15:20:36 -070031 uid= Set the default user.
32 bs= Set the block size.
33 unhide Show otherwise hidden files.
34 undelete Show deleted files in lists.
35 adinicb Embed data in the inode (default)
36 noadinicb Don't embed data in the inode
37 shortad Use short ad's
38 longad Use long ad's (default)
39 nostrict Unset strict conformance
40 iocharset= Set the NLS character set
Mauro Carvalho Chehabc9817ad2020-02-17 17:12:29 +010041 =========== ======================================
Linus Torvalds1da177e2005-04-16 15:20:36 -070042
Phillip Susi0e6b3e52006-03-25 03:08:14 -080043The uid= and gid= options need a bit more explaining. They will accept a
Jan Kara6ccd5192018-02-22 10:52:34 +010044decimal numeric value and all inodes on that mount will then appear as
45belonging to that uid and gid. Mount options also accept the string "forget".
46The forget option causes all IDs to be written to disk as -1 which is a way
47of UDF standard to indicate that IDs are not supported for these files .
Phillip Susi0e6b3e52006-03-25 03:08:14 -080048
Jan Kara6ccd5192018-02-22 10:52:34 +010049For typical desktop use of removable media, you should set the ID to that of
50the interactively logged on user, and also specify the forget option. This way
51the interactive user will always see the files on the disk as belonging to him.
Phillip Susi0e6b3e52006-03-25 03:08:14 -080052
Linus Torvalds1da177e2005-04-16 15:20:36 -070053The remaining are for debugging and disaster recovery:
54
Mauro Carvalho Chehabc9817ad2020-02-17 17:12:29 +010055 ===== ================================
56 novrs Skip volume sequence recognition
57 ===== ================================
Linus Torvalds1da177e2005-04-16 15:20:36 -070058
59The following expect a offset from 0.
60
Mauro Carvalho Chehabc9817ad2020-02-17 17:12:29 +010061 ========== =================================================
Linus Torvalds1da177e2005-04-16 15:20:36 -070062 session= Set the CDROM session (default= last session)
63 anchor= Override standard anchor location. (default= 256)
Linus Torvalds1da177e2005-04-16 15:20:36 -070064 lastblock= Set the last block of the filesystem/
Mauro Carvalho Chehabc9817ad2020-02-17 17:12:29 +010065 ========== =================================================
Linus Torvalds1da177e2005-04-16 15:20:36 -070066
Linus Torvalds1da177e2005-04-16 15:20:36 -070067-------------------------------------------------------------------------------
68
69
70For the latest version and toolset see:
Jan Kara503c3112017-10-16 11:55:52 +020071 https://github.com/pali/udftools
Linus Torvalds1da177e2005-04-16 15:20:36 -070072
73Documentation on UDF and ECMA 167 is available FREE from:
Mauro Carvalho Chehabc9817ad2020-02-17 17:12:29 +010074 - http://www.osta.org/
Alexander A. Klimov248727a2020-07-13 22:07:38 +020075 - https://www.ecma-international.org/