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

# 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
	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.

	  To learn more about Access Control Lists, visit the POSIX ACLs for
	  Linux website <http://acl.bestbits.at/>.

	  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_ENCRYPTION
	tristate "Ext4 Encryption"
	depends on EXT4_FS
	select CRYPTO_AES
	select CRYPTO_CBC
	select CRYPTO_ECB
	select CRYPTO_XTS
	select CRYPTO_CTS
	select CRYPTO_CTR
	select CRYPTO_SHA256
	select KEYS
	select ENCRYPTED_KEYS
	help
	  Enable encryption of ext4 files and directories.  This
	  feature is similar to ecryptfs, but it is more memory
	  efficient since it avoids caching the encrypted and
	  decrypted pages in the page cache.

config EXT4_FS_ENCRYPTION
	bool
	default y
	depends on EXT4_ENCRYPTION

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
c290ea01 JK	1	# Ext3 configs are here for backward compatibility with old configs which may
	2	# have EXT3_FS set but not EXT4_FS set and thus would result in non-bootable
	3	# kernels after the removal of ext3 driver.
	4	config EXT3_FS
	5	tristate "The Extended 3 (ext3) filesystem"
	6	# These must match EXT4_FS selects...
	7	select EXT4_FS
	8	select JBD2
	9	select CRC16
	10	select CRYPTO
	11	select CRYPTO_CRC32C
	12	help
	13	This config option is here only for backward compatibility. ext3
	14	filesystem is now handled by the ext4 driver.
	15
	16	config EXT3_FS_POSIX_ACL
	17	bool "Ext3 POSIX Access Control Lists"
	18	depends on EXT3_FS
	19	select EXT4_FS_POSIX_ACL
	20	select FS_POSIX_ACL
	21	help
	22	This config option is here only for backward compatibility. ext3
	23	filesystem is now handled by the ext4 driver.
	24
	25	config EXT3_FS_SECURITY
	26	bool "Ext3 Security Labels"
	27	depends on EXT3_FS
	28	select EXT4_FS_SECURITY
	29	help
	30	This config option is here only for backward compatibility. ext3
	31	filesystem is now handled by the ext4 driver.
	32
6da0b38f AD	33	config EXT4_FS
6da0b38f AD	34	tristate "The Extended 4 (ext4) filesystem"
c290ea01	35	# Please update EXT3_FS selects when changing these
6da0b38f AD	36	select JBD2
6da0b38f AD	37	select CRC16
0441984a DW	38	select CRYPTO
0441984a DW	39	select CRYPTO_CRC32C
6da0b38f AD	40	help
	41	This is the next generation of the ext3 filesystem.
	42
	43	Unlike the change from ext2 filesystem to ext3 filesystem,
	44	the on-disk format of ext4 is not forwards compatible with
	45	ext3; it is based on extent maps and it supports 48-bit
	46	physical block numbers. The ext4 filesystem also supports delayed
	47	allocation, persistent preallocation, high resolution time stamps,
	48	and a number of other features to improve performance and speed
	49	up fsck time. For more information, please see the web pages at
	50	http://ext4.wiki.kernel.org.
	51
c8962f4b JK	52	The ext4 filesystem supports mounting an ext3 filesystem; while there
	53	are some performance gains from the delayed allocation and inode
	54	table readahead, the best performance gains require enabling ext4
	55	features in the filesystem using tune2fs, or formatting a new
	56	filesystem as an ext4 filesystem initially. Without explicit enabling
	57	of ext4 features, the on disk filesystem format stays fully backward
	58	compatible.
6da0b38f AD	59
	60	To compile this file system support as a module, choose M here. The
	61	module will be called ext4.
	62
	63	If unsure, say N.
	64
c290ea01	65	config EXT4_USE_FOR_EXT2
d4eb6dee	66	bool "Use ext4 for ext2 file systems"
84c66473	67	depends on EXT4_FS
c290ea01	68	depends on EXT2_FS=n
24b58424 TT	69	default y
24b58424 TT	70	help
c290ea01 JK	71	Allow the ext4 file system driver code to be used for ext2
c290ea01 JK	72	file system mounts. This allows users to reduce their
24b58424 TT	73	compiled kernel size by using one file system driver for
	74	ext2, ext3, and ext4 file systems.
	75
6da0b38f AD	76	config EXT4_FS_POSIX_ACL
6da0b38f AD	77	bool "Ext4 POSIX Access Control Lists"
96465efe	78	depends on EXT4_FS
6da0b38f AD	79	select FS_POSIX_ACL
	80	help
	81	POSIX Access Control Lists (ACLs) support permissions for users and
	82	groups beyond the owner/group/world scheme.
	83
	84	To learn more about Access Control Lists, visit the POSIX ACLs for
	85	Linux website <http://acl.bestbits.at/>.
	86
	87	If you don't know what Access Control Lists are, say N
	88
	89	config EXT4_FS_SECURITY
	90	bool "Ext4 Security Labels"
96465efe	91	depends on EXT4_FS
6da0b38f AD	92	help
	93	Security labels support alternative access control models
	94	implemented by security modules like SELinux. This option
	95	enables an extended attribute handler for file security
	96	labels in the ext4 filesystem.
	97
	98	If you are not using a security module that requires using
	99	extended attributes for file security labels, say N.
6ba495e9	100
fb63e548 HX	101	config EXT4_ENCRYPTION
fb63e548 HX	102	tristate "Ext4 Encryption"
b17655fb TT	103	depends on EXT4_FS
	104	select CRYPTO_AES
	105	select CRYPTO_CBC
	106	select CRYPTO_ECB
	107	select CRYPTO_XTS
	108	select CRYPTO_CTS
71dea01e	109	select CRYPTO_CTR
b17655fb TT	110	select CRYPTO_SHA256
	111	select KEYS
	112	select ENCRYPTED_KEYS
	113	help
	114	Enable encryption of ext4 files and directories. This
	115	feature is similar to ecryptfs, but it is more memory
	116	efficient since it avoids caching the encrypted and
	117	decrypted pages in the page cache.
	118
fb63e548 HX	119	config EXT4_FS_ENCRYPTION
	120	bool
	121	default y
	122	depends on EXT4_ENCRYPTION
	123
6ba495e9 TT	124	config EXT4_DEBUG
	125	bool "EXT4 debugging support"
	126	depends on EXT4_FS
	127	help
	128	Enables run-time debugging support for the ext4 filesystem.
	129
	130	If you select Y here, then you will be able to turn on debugging
7f3e3c7c TT	131	with a command such as:
7f3e3c7c TT	132	echo 1 > /sys/module/ext4/parameters/mballoc_debug