.BR mke2fs (8).
It controls the default parameters used by
.BR mke2fs (8)
-when it is creating ext2, ext3, or ext4 filesystems.
+when it is creating ext2, ext3, or ext4 file systems.
.PP
The
.I mke2fs.conf
.BR mke2fs (8).
In general, these defaults may be overridden by a definition in the
.B fs_types
-stanza, or by an command-line option provided by the user.
+stanza, or by a command-line option provided by the user.
.TP
.I [fs_types]
Contains relations which define defaults that should be used for specific
options to
.BR mke2fs (8),
respectively.
+.TP
+.I [devices]
+Contains relations which define defaults for specific devices.
.SH THE [options] STANZA
The following relations are defined in the
.I [options]
stanza.
.TP
.I proceed_delay
-If this relation is set to a positive integer, then if mke2fs will
-proceed after waiting
+If this relation is set to a positive integer, then mke2fs will
+wait
.I proceed_delay
-seconds, after asking the user for permission to proceed, even if the
+seconds after asking the user for permission to proceed and
+then continue, even if the
user has not answered the question. Defaults to 0, which means to wait
until the user answers the question one way or another.
+.TP
+.I sync_kludge
+If this relation is set to a positive integer, then while writing the
+inode table, mke2fs will request the operating system flush out pending
+writes to initialize the inode table every
+.I sync_kludge
+block groups. This is needed to work around buggy kernels that don't
+handle writeback throttling correctly.
.SH THE [defaults] STANZA
The following relations are defined in the
.I [defaults]
stanza.
.TP
-.I base_features
-This relation specifies the filesystems features which are enabled in
-newly created filesystems. It may be overridden by the
-.I base_features
-relation found in the filesystem or usage type subsection of
-the
-.I [fs_types]
-stanza.
-.TP
-.I default_features
-This relation specifies a set of features that should be added or
-removed to the features listed in the
-.I base_features
-relation. It may be overridden by the filesystem-specific
-.I default_features
-in the filesystem or usage type subsection of
-.IR [fs_types] ,
-and by the
-.B -O
-command-line option
-to
-.BR mke2fs (8).
-.TP
-.I enable_periodic_fsck
-This boolean relation specifies whether periodic filesystem checks should be
-enforced at boot time. If set to true, checks will be forced every
-180 days, or after a random number of mounts. These values may
-be changed later via the
-.B -i
-and
-.B -c
-command-line options to
-.BR tune2fs (8).
-.TP
-.I force_undo
-This boolean relation, if set to a value of true, forces
+.I creator_os
+This relation specifies the "creator operating system" for the
+file system unless it is overridden on the command line.
+The default value is the OS for which the
.B mke2fs
-to always try to create an undo file, even if the undo file might be
-huge and it might extend the time to create the filesystem image
-because the inode table isn't being initialized lazily.
+executable was compiled.
.TP
.I fs_type
-This relation specifies the default filesystem type if the user does not
+This relation specifies the default file system type if the user does not
specify it via the
.B \-t
option, or if
.BI mkfs. fs-type\fR.
If both the user and the
.B mke2fs.conf
-file do not specify a default filesystem type, mke2fs will use a
-default filesystem type of
-.IR ext3
+file do not specify a default file system type, mke2fs will use a
+default file system type of
+.I ext3
if a journal was requested via a command-line option, or
.I ext2
if not.
etc.) can also be specified in the
.I defaults
stanza to specify the default value to be used if the user does not
-specify one on the command line, and the filesystem-type
+specify one on the command line, and the file system-type
specific section of the configuration file does not specify a default value.
.SH THE [fs_types] STANZA
Each tag in the
.I [fs_types]
-stanza names a filesystem type or usage type which can be specified via the
+stanza names a file system type or usage type which can be specified via the
.B \-t
or
.B \-T
.P
The
.B mke2fs
-program constructs a list of fs_types by concatenating the filesystem
+program constructs a list of fs_types by concatenating the file system
type (i.e., ext2, ext3, etc.) with the usage type list. For most
configuration options,
.B mke2fs
will look for a subsection in the
.I [fs_types]
stanza corresponding with each entry in the constructed list, with later
-entries overriding earlier filesystem or usage types.
+entries overriding earlier file system or usage types.
For
example, consider the following
.B mke2fs.conf
.P
If mke2fs started with a program name of
.BR mke2fs.ext4 ,
-then the filesystem type of ext4 will be used. If the filesystem is
+then the file system type of ext4 will be used. If the file system is
smaller than 3 megabytes, and no usage type is specified, then
.B mke2fs
will use a default
.I inode_size
relation, but since the later entries in the fs_types list supersede
earlier ones, the configuration parameter for fs_types.floppy.inode_size
-will be used, so the filesystem will have an inode size of 128.
+will be used, so the file system will have an inode size of 128.
.P
The exception to this resolution is the
.I features
tag, which specifies a set of changes to the features used by the
-filesystem, and which is cumulative. So in the above example, first
+file system, and which is cumulative. So in the above example, first
the configuration relation defaults.base_features would enable an
initial feature set with the sparse_super, filetype, resize_inode, and
dir_index features enabled. Then configuration relation
fs_types.ext4.features would enable the extents and flex_bg
features, and finally the configuration relation
fs_types.floppy.features would remove
-the resize_inode feature, resulting in a filesystem feature set
+the resize_inode feature, resulting in a file system feature set
consisting of the sparse_super, filetype, dir_index,
extents_and flex_bg features.
.P
-For each filesystem type, the following tags may be used in that
+For each file system type, the following tags may be used in that
fs_type's subsection. These tags may also be used in the
.I default
section:
.TP
.I base_features
This relation specifies the features which are initially enabled for this
-filesystem type. Only one
+file system type. Only one
.I base_features
will be used, so if there are multiple entries in the fs_types list
whose subsections define the
relation, only the last will be used by
.BR mke2fs (8).
.TP
+.I enable_periodic_fsck
+This boolean relation specifies whether periodic file system checks should be
+enforced at boot time. If set to true, checks will be forced every
+180 days, or after a random number of mounts. These values may
+be changed later via the
+.B -i
+and
+.B -c
+command-line options to
+.BR tune2fs (8).
+.TP
.I errors
Change the behavior of the kernel code when errors are detected.
-In all cases, a filesystem error will cause
+In all cases, a file system error will cause
.BR e2fsck (8)
-to check the filesystem on the next boot.
+to check the file system on the next boot.
.I errors
can be one of the following:
.RS 1.2i
Continue normal execution.
.TP
.B remount-ro
-Remount filesystem read-only.
+Remount file system read-only.
.TP
.B panic
Cause a kernel panic.
.I features
This relation specifies a comma-separated list of features edit
requests which modify the feature set
-used by the newly constructed filesystem. The syntax is the same as the
+used by the newly constructed file system. The syntax is the same as the
.B -O
command-line option to
.BR mke2fs (8);
relation specified in the fs_types list will be applied in the order
found in the fs_types list.
.TP
+.I force_undo
+This boolean relation, if set to a value of true, forces
+.B mke2fs
+to always try to create an undo file, even if the undo file might be
+huge and it might extend the time to create the file system image
+because the inode table isn't being initialized lazily.
+.TP
.I default_features
This relation specifies set of features which should be enabled or
disabled after applying the features listed in the
enabled, the inode table will
not be fully initialized by
.BR mke2fs (8).
-This speeds up filesystem
+This speeds up file system
initialization noticeably, but it requires the kernel to finish
-initializing the filesystem in the background when the filesystem is
+initializing the file system in the background when the file system is
first mounted.
.TP
+.I lazy_journal_init
+This boolean relation specifies whether the journal inode should be
+lazily initialized. It only has meaning if the has_journal feature is
+enabled. If lazy_journal_init is true, the journal inode will not be
+fully zeroed out by
+.BR mke2fs .
+This speeds up file system initialization noticeably, but carries some
+small risk if the system crashes before the journal has been overwritten
+entirely one time.
+.TP
.I journal_location
This relation specifies the location of the journal.
.TP
feature enabled should be created with 0, 1, or 2 backup superblocks.
.TP
.I packed_meta_blocks
-This boolean relation specifes whether the allocation bitmaps, inode
+This boolean relation specifies whether the allocation bitmaps, inode
table, and journal should be located at the beginning of the file system.
.TP
.I inode_ratio
specify one on the command line.
.TP
.I reserved_ratio
-This relation specifies the default percentage of filesystem blocks
+This relation specifies the default percentage of file system blocks
reserved for the super-user, if the user does not specify one on the command
line.
.TP
.I hash_alg
This relation specifies the default hash algorithm used for the
-new filesystems with hashed b-tree directories. Valid algorithms
+new file systems with hashed b-tree directories. Valid algorithms
accepted are:
.IR legacy ,
.IR half_md4 ,
.TP
.I flex_bg_size
This relation specifies the number of block groups that will be packed
-together to create one large virtual block group on an ext4 filesystem.
+together to create one large virtual block group on an ext4 file system.
This improves meta-data locality and performance on meta-data heavy
workloads. The number of groups must be a power of 2 and may only be
-specified if the flex_bg filesystem feature is enabled.
+specified if the flex_bg file system feature is enabled.
.TP
.I options
This relation specifies additional extended options which should be
option. This can be used to configure the default extended options used
by
.BR mke2fs (8)
-on a per-filesystem type basis.
+on a per-file system type basis.
.TP
.I discard
This boolean relation specifies whether the
.BR mke2fs (8)
-should attempt to discard device prior to filesystem creation.
+should attempt to discard device prior to file system creation.
.TP
.I cluster_size
This relation specifies the default cluster size if the bigalloc file
.TP
.I make_hugefiles
This boolean relation enables the creation of pre-allocated files as
-part of formatting the file system.
+part of formatting the file system. The extent tree blocks for these
+pre-allocated files will be placed near the beginning of the file
+system, so that if all of the other metadata blocks are also configured
+to be placed near the beginning of the file system (by disabling the
+backup superblocks, using the packed_meta_blocks option, etc.), the data
+blocks of the pre-allocated files will be contiguous.
+.TP
+.I hugefiles_dir
+This relation specifies the directory where huge files are created,
+relative to the file system root.
.TP
.I hugefiles_uid
This relation controls the user ownership for all of the files and
This relation specifies the (zero-padded) width of the field for the
huge file number.
.TP
+.I warn_y2038_dates
+This boolean relation specifies whether mke2fs will issue a warning
+when creating a file system with 128 byte inodes (and so therefore will
+not support dates after January 19th, 2038). The default value is true,
+except for file systems created for the GNU Hurd since it only supports
+128-byte inodes.
+.TP
.I zero_hugefiles
This boolean relation specifies whether or not zero blocks will be
written to the hugefiles while
-.BR mke2fs(8)
+.BR mke2fs (8)
is creating them. By default, zero blocks will be written to the huge
files to avoid stale data from being made available to potentially
untrusted user programs, unless the device supports a discard/trim
known that the disk has been previously erased, or if the user programs
that will have access to the huge files are trusted to not reveal stale
data.
+.TP
+.I encoding
+This relation defines the file name encoding to be used if the casefold
+feature is enabled. Currently the only valid encoding is utf8-12.1 or
+utf8, which requests the most recent Unicode version; since 12.1 is the only
+available Unicode version, utf8 and utf8-12.1 have the same result.
+.I encoding_flags
+This relation defines encoding-specific flags. For utf8 encodings, the
+only available flag is strict, which will cause attempts to create file
+names containing invalid Unicode characters to be rejected by the
+kernel. Strict mode is not enabled by default.
.SH THE [devices] STANZA
Each tag in the
.I [devices]
projects / platform / upstream / e2fsprogs.git / blobdiff