buildroot/fs/ext2/Config.in

config BR2_TARGET_ROOTFS_EXT2
	bool "ext2/3/4 root filesystem"
	select BR2_PACKAGE_HOST_E2FSPROGS
	help
	  Build an ext2/3/4 root filesystem

if BR2_TARGET_ROOTFS_EXT2

config BR2_TARGET_ROOTFS_EXT2_2
	bool

choice
	bool "ext2/3/4 variant"
	default BR2_TARGET_ROOTFS_EXT2_2r1

config BR2_TARGET_ROOTFS_EXT2_2r1
	bool "ext2 (rev1)"
	select BR2_TARGET_ROOTFS_EXT2_2

config BR2_TARGET_ROOTFS_EXT2_3
	bool "ext3"

config BR2_TARGET_ROOTFS_EXT2_4
	bool "ext4"

endchoice

config BR2_TARGET_ROOTFS_EXT2_GEN
	int
	default 2 if BR2_TARGET_ROOTFS_EXT2_2
	default 3 if BR2_TARGET_ROOTFS_EXT2_3
	default 4 if BR2_TARGET_ROOTFS_EXT2_4

config BR2_TARGET_ROOTFS_EXT2_LABEL
	string "filesystem label"
	default "rootfs"

config BR2_TARGET_ROOTFS_EXT2_SIZE
	string "exact size"
	default BR2_TARGET_ROOTFS_EXT2_BLOCKS if BR2_TARGET_ROOTFS_EXT2_BLOCKS_WRAP # legacy 2017.08
	default "60M"
	help
	  The size of the filesystem image. If it does not have a
	  suffix, it is interpreted as power-of-two kilobytes. If it is
	  suffixed by 'k', 'm', 'g', 't' (either upper-case or
	  lower-case), then it is interpreted in power-of-two kilobytes,
	  megabytes, gigabytes, terabytes, etc.

config BR2_TARGET_ROOTFS_EXT2_INODES
	int "exact number of inodes (leave at 0 for auto calculation)"
	default 0

config BR2_TARGET_ROOTFS_EXT2_INODE_SIZE
	int "inode size"
	default 256
	help
	  Set the size of inodes, in bytes, as a power of 2 larger or
	  equal to 128.

	  Set to 0 to let the filesystem generator decide based on the
	  file system size. If unsure, keep the default, 256.

	  Note: 128-byte inodes suffer of the Y2K38 problem, and can't
	  store timestamps beyond 2038-01-19 03:14:07Z.

config BR2_TARGET_ROOTFS_EXT2_RESBLKS
	int "reserved blocks percentage"
	default 5
	help
	  The number of blocks on the filesystem (as a percentage of the
	  total number of blocks), that are reserved for use by root.
	  Traditionally, this has been 5%, and all ext-related tools
	  still default to reserving 5% when creating a new ext
	  filesystem.

config BR2_TARGET_ROOTFS_EXT2_MKFS_OPTIONS
	string "additional mke2fs options"
	default "-O ^64bit"
	help
	  Specify a space-separated list of mke2fs options, including
	  any ext2/3/4 filesystem features.

	  For more information about the mke2fs options, see the manual
	  page mke2fs(8).

	  For more information about the ext2/3/4 features which can be
	  set, see the manual page ext4(5).

	  The default is "-O ^64bit", i.e. disable 64-bit filesystem
	  support. This default value has been chosen because U-Boot
	  versions before 2017.02 don't support this filesystem
	  option: using it may make the filesystem unreadable by
	  U-Boot.

choice
	prompt "Compression method"
	default BR2_TARGET_ROOTFS_EXT2_NONE
	help
	  Select compressor for ext2/3/4 filesystem of the root
	  filesystem

config BR2_TARGET_ROOTFS_EXT2_NONE
	bool "no compression"
	help
	  Do not compress the ext2/3/4 filesystem.

config BR2_TARGET_ROOTFS_EXT2_GZIP
	bool "gzip"
	help
	  Do compress the ext2/3/4 filesystem with gzip.

config BR2_TARGET_ROOTFS_EXT2_BZIP2
	bool "bzip2"
	help
	  Do compress the ext2/3/4 filesystem with bzip2.

config BR2_TARGET_ROOTFS_EXT2_LZ4
	bool "lz4"
	help
	  Do compress the ext2 filesystem with lz4.

config BR2_TARGET_ROOTFS_EXT2_LZMA
	bool "lzma"
	help
	  Do compress the ext2/3/4 filesystem with lzma.

config BR2_TARGET_ROOTFS_EXT2_LZO
	bool "lzo"
	help
	  Do compress the ext2 filesystem with lzop.

config BR2_TARGET_ROOTFS_EXT2_XZ
	bool "xz"
	help
	  Do compress the ext2 filesystem with xz.

config BR2_TARGET_ROOTFS_EXT2_ZSTD
	bool "zstd"
	help
	  Do compress the ext2 filesystem with zstd.

endchoice

endif # BR2_TARGET_ROOTFS_EXT2