v4.19.13 snapshot.
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+*
+* Documentation/filesystems/udf.txt
+*
+
+If you encounter problems with reading UDF discs using this driver,
+please report them according to MAINTAINERS file.
+
+Write support requires a block driver which supports writing. Currently
+dvd+rw drives and media support true random sector writes, and so a udf
+filesystem on such devices can be directly mounted read/write. CD-RW
+media however, does not support this. Instead the media can be formatted
+for packet mode using the utility cdrwtool, then the pktcdvd driver can
+be bound to the underlying cd device to provide the required buffering
+and read-modify-write cycles to allow the filesystem random sector writes
+while providing the hardware with only full packet writes. While not
+required for dvd+rw media, use of the pktcdvd driver often enhances
+performance due to very poor read-modify-write support supplied internally
+by drive firmware.
+
+-------------------------------------------------------------------------------
+The following mount options are supported:
+
+ gid= Set the default group.
+ umask= Set the default umask.
+ mode= Set the default file permissions.
+ dmode= Set the default directory permissions.
+ uid= Set the default user.
+ bs= Set the block size.
+ unhide Show otherwise hidden files.
+ undelete Show deleted files in lists.
+ adinicb Embed data in the inode (default)
+ noadinicb Don't embed data in the inode
+ shortad Use short ad's
+ longad Use long ad's (default)
+ nostrict Unset strict conformance
+ iocharset= Set the NLS character set
+
+The uid= and gid= options need a bit more explaining. They will accept a
+decimal numeric value and all inodes on that mount will then appear as
+belonging to that uid and gid. Mount options also accept the string "forget".
+The forget option causes all IDs to be written to disk as -1 which is a way
+of UDF standard to indicate that IDs are not supported for these files .
+
+For typical desktop use of removable media, you should set the ID to that of
+the interactively logged on user, and also specify the forget option. This way
+the interactive user will always see the files on the disk as belonging to him.
+
+The remaining are for debugging and disaster recovery:
+
+ novrs Skip volume sequence recognition
+
+The following expect a offset from 0.
+
+ session= Set the CDROM session (default= last session)
+ anchor= Override standard anchor location. (default= 256)
+ lastblock= Set the last block of the filesystem/
+
+-------------------------------------------------------------------------------
+
+
+For the latest version and toolset see:
+ https://github.com/pali/udftools
+
+Documentation on UDF and ECMA 167 is available FREE from:
+ http://www.osta.org/
+ http://www.ecma-international.org/