1config EXT4_FS
2	tristate "The Extended 4 (ext4) filesystem"
3	select JBD2
4	select CRC16
5	help
6	  This is the next generation of the ext3 filesystem.
7
8	  Unlike the change from ext2 filesystem to ext3 filesystem,
9	  the on-disk format of ext4 is not forwards compatible with
10	  ext3; it is based on extent maps and it supports 48-bit
11	  physical block numbers.  The ext4 filesystem also supports delayed
12	  allocation, persistent preallocation, high resolution time stamps,
13	  and a number of other features to improve performance and speed
14	  up fsck time.  For more information, please see the web pages at
15	  http://ext4.wiki.kernel.org.
16
17	  The ext4 filesystem will support mounting an ext3
18	  filesystem; while there will be some performance gains from
19	  the delayed allocation and inode table readahead, the best
20	  performance gains will require enabling ext4 features in the
21	  filesystem, or formatting a new filesystem as an ext4
22	  filesystem initially.
23
24	  To compile this file system support as a module, choose M here. The
25	  module will be called ext4.
26
27	  If unsure, say N.
28
29config EXT4_USE_FOR_EXT23
30	bool "Use ext4 for ext2/ext3 file systems"
31	depends on EXT4_FS
32	depends on EXT3_FS=n || EXT2_FS=n
33	default y
34	help
35	  Allow the ext4 file system driver code to be used for ext2 or
36	  ext3 file system mounts.  This allows users to reduce their
37	  compiled kernel size by using one file system driver for
38	  ext2, ext3, and ext4 file systems.
39
40config EXT4_FS_XATTR
41	bool "Ext4 extended attributes"
42	depends on EXT4_FS
43	default y
44	help
45	  Extended attributes are name:value pairs associated with inodes by
46	  the kernel or by users (see the attr(5) manual page, or visit
47	  <http://acl.bestbits.at/> for details).
48
49	  If unsure, say N.
50
51	  You need this for POSIX ACL support on ext4.
52
53config EXT4_FS_POSIX_ACL
54	bool "Ext4 POSIX Access Control Lists"
55	depends on EXT4_FS_XATTR
56	select FS_POSIX_ACL
57	help
58	  POSIX Access Control Lists (ACLs) support permissions for users and
59	  groups beyond the owner/group/world scheme.
60
61	  To learn more about Access Control Lists, visit the POSIX ACLs for
62	  Linux website <http://acl.bestbits.at/>.
63
64	  If you don't know what Access Control Lists are, say N
65
66config EXT4_FS_SECURITY
67	bool "Ext4 Security Labels"
68	depends on EXT4_FS_XATTR
69	help
70	  Security labels support alternative access control models
71	  implemented by security modules like SELinux.  This option
72	  enables an extended attribute handler for file security
73	  labels in the ext4 filesystem.
74
75	  If you are not using a security module that requires using
76	  extended attributes for file security labels, say N.
77
78config EXT4_DEBUG
79	bool "EXT4 debugging support"
80	depends on EXT4_FS
81	help
82	  Enables run-time debugging support for the ext4 filesystem.
83
84	  If you select Y here, then you will be able to turn on debugging
85	  with a command such as "echo 1 > /sys/kernel/debug/ext4/mballoc-debug"
86