[linux-2.6-block.git] / fs / ext4 / Kconfig

# SPDX-License-Identifier: GPL-2.0-only
# Ext3 configs are here for backward compatibility with old configs which may
# have EXT3_FS set but not EXT4_FS set and thus would result in non-bootable
# kernels after the removal of ext3 driver.
config EXT3_FS
	tristate "The Extended 3 (ext3) filesystem"
	# These must match EXT4_FS selects...
	select EXT4_FS
	select JBD2
	select CRC16
	select CRYPTO
	select CRYPTO_CRC32C
	help
	  This config option is here only for backward compatibility. ext3
	  filesystem is now handled by the ext4 driver.

config EXT3_FS_POSIX_ACL
	bool "Ext3 POSIX Access Control Lists"
	depends on EXT3_FS
	select EXT4_FS_POSIX_ACL
	select FS_POSIX_ACL
	help
	  This config option is here only for backward compatibility. ext3
	  filesystem is now handled by the ext4 driver.

config EXT3_FS_SECURITY
	bool "Ext3 Security Labels"
	depends on EXT3_FS
	select EXT4_FS_SECURITY
	help
	  This config option is here only for backward compatibility. ext3
	  filesystem is now handled by the ext4 driver.

config EXT4_FS
	tristate "The Extended 4 (ext4) filesystem"
	# Please update EXT3_FS selects when changing these
	select JBD2
	select CRC16
	select CRYPTO
	select CRYPTO_CRC32C
	select FS_IOMAP
	help
	  This is the next generation of the ext3 filesystem.

	  Unlike the change from ext2 filesystem to ext3 filesystem,
	  the on-disk format of ext4 is not forwards compatible with
	  ext3; it is based on extent maps and it supports 48-bit
	  physical block numbers.  The ext4 filesystem also supports delayed
	  allocation, persistent preallocation, high resolution time stamps,
	  and a number of other features to improve performance and speed
	  up fsck time.  For more information, please see the web pages at
	  http://ext4.wiki.kernel.org.

	  The ext4 filesystem supports mounting an ext3 filesystem; while there
	  are some performance gains from the delayed allocation and inode
	  table readahead, the best performance gains require enabling ext4
	  features in the filesystem using tune2fs, or formatting a new
	  filesystem as an ext4 filesystem initially. Without explicit enabling
	  of ext4 features, the on disk filesystem format stays fully backward
	  compatible.

	  To compile this file system support as a module, choose M here. The
	  module will be called ext4.

	  If unsure, say N.

config EXT4_USE_FOR_EXT2
	bool "Use ext4 for ext2 file systems"
	depends on EXT4_FS
	depends on EXT2_FS=n
	default y
	help
	  Allow the ext4 file system driver code to be used for ext2
	  file system mounts.  This allows users to reduce their
	  compiled kernel size by using one file system driver for
	  ext2, ext3, and ext4 file systems.

config EXT4_FS_POSIX_ACL
	bool "Ext4 POSIX Access Control Lists"
	depends on EXT4_FS
	select FS_POSIX_ACL
	help
	  POSIX Access Control Lists (ACLs) support permissions for users and
	  groups beyond the owner/group/world scheme.

	  If you don't know what Access Control Lists are, say N

config EXT4_FS_SECURITY
	bool "Ext4 Security Labels"
	depends on EXT4_FS
	help
	  Security labels support alternative access control models
	  implemented by security modules like SELinux.  This option
	  enables an extended attribute handler for file security
	  labels in the ext4 filesystem.

	  If you are not using a security module that requires using
	  extended attributes for file security labels, say N.

config EXT4_DEBUG
	bool "Ext4 debugging support"
	depends on EXT4_FS
	help
	  Enables run-time debugging support for the ext4 filesystem.

	  If you select Y here, then you will be able to turn on debugging
	  with a command such as:
		echo 1 > /sys/module/ext4/parameters/mballoc_debug
Commit	Line	Data
ec8f24b7	1	# SPDX-License-Identifier: GPL-2.0-only
c290ea01 JK	2	# Ext3 configs are here for backward compatibility with old configs which may
	3	# have EXT3_FS set but not EXT4_FS set and thus would result in non-bootable
	4	# kernels after the removal of ext3 driver.
	5	config EXT3_FS
	6	tristate "The Extended 3 (ext3) filesystem"
	7	# These must match EXT4_FS selects...
	8	select EXT4_FS
	9	select JBD2
	10	select CRC16
	11	select CRYPTO
	12	select CRYPTO_CRC32C
	13	help
	14	This config option is here only for backward compatibility. ext3
	15	filesystem is now handled by the ext4 driver.
	16
	17	config EXT3_FS_POSIX_ACL
	18	bool "Ext3 POSIX Access Control Lists"
	19	depends on EXT3_FS
	20	select EXT4_FS_POSIX_ACL
	21	select FS_POSIX_ACL
	22	help
	23	This config option is here only for backward compatibility. ext3
	24	filesystem is now handled by the ext4 driver.
	25
	26	config EXT3_FS_SECURITY
	27	bool "Ext3 Security Labels"
	28	depends on EXT3_FS
	29	select EXT4_FS_SECURITY
	30	help
	31	This config option is here only for backward compatibility. ext3
	32	filesystem is now handled by the ext4 driver.
	33
6da0b38f AD	34	config EXT4_FS
6da0b38f AD	35	tristate "The Extended 4 (ext4) filesystem"
c290ea01	36	# Please update EXT3_FS selects when changing these
6da0b38f AD	37	select JBD2
6da0b38f AD	38	select CRC16
0441984a DW	39	select CRYPTO
0441984a DW	40	select CRYPTO_CRC32C
545052e9	41	select FS_IOMAP
6da0b38f AD	42	help
	43	This is the next generation of the ext3 filesystem.
	44
	45	Unlike the change from ext2 filesystem to ext3 filesystem,
	46	the on-disk format of ext4 is not forwards compatible with
	47	ext3; it is based on extent maps and it supports 48-bit
	48	physical block numbers. The ext4 filesystem also supports delayed
	49	allocation, persistent preallocation, high resolution time stamps,
	50	and a number of other features to improve performance and speed
	51	up fsck time. For more information, please see the web pages at
	52	http://ext4.wiki.kernel.org.
	53
c8962f4b JK	54	The ext4 filesystem supports mounting an ext3 filesystem; while there
	55	are some performance gains from the delayed allocation and inode
	56	table readahead, the best performance gains require enabling ext4
	57	features in the filesystem using tune2fs, or formatting a new
	58	filesystem as an ext4 filesystem initially. Without explicit enabling
	59	of ext4 features, the on disk filesystem format stays fully backward
	60	compatible.
6da0b38f AD	61
	62	To compile this file system support as a module, choose M here. The
	63	module will be called ext4.
	64
	65	If unsure, say N.
	66
c290ea01	67	config EXT4_USE_FOR_EXT2
d4eb6dee	68	bool "Use ext4 for ext2 file systems"
84c66473	69	depends on EXT4_FS
c290ea01	70	depends on EXT2_FS=n
24b58424 TT	71	default y
24b58424 TT	72	help
c290ea01 JK	73	Allow the ext4 file system driver code to be used for ext2
c290ea01 JK	74	file system mounts. This allows users to reduce their
24b58424 TT	75	compiled kernel size by using one file system driver for
	76	ext2, ext3, and ext4 file systems.
	77
6da0b38f AD	78	config EXT4_FS_POSIX_ACL
6da0b38f AD	79	bool "Ext4 POSIX Access Control Lists"
96465efe	80	depends on EXT4_FS
6da0b38f AD	81	select FS_POSIX_ACL
	82	help
	83	POSIX Access Control Lists (ACLs) support permissions for users and
	84	groups beyond the owner/group/world scheme.
	85
6da0b38f AD	86	If you don't know what Access Control Lists are, say N
	87
	88	config EXT4_FS_SECURITY
	89	bool "Ext4 Security Labels"
96465efe	90	depends on EXT4_FS
6da0b38f AD	91	help
	92	Security labels support alternative access control models
	93	implemented by security modules like SELinux. This option
	94	enables an extended attribute handler for file security
	95	labels in the ext4 filesystem.
	96
	97	If you are not using a security module that requires using
	98	extended attributes for file security labels, say N.
6ba495e9 TT	99
6ba495e9 TT	100	config EXT4_DEBUG
231fe82b	101	bool "Ext4 debugging support"
6ba495e9 TT	102	depends on EXT4_FS
	103	help
	104	Enables run-time debugging support for the ext4 filesystem.
	105
	106	If you select Y here, then you will be able to turn on debugging
7f3e3c7c TT	107	with a command such as:
7f3e3c7c TT	108	echo 1 > /sys/module/ext4/parameters/mballoc_debug