1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
|
# 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 if FS_DAX
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
bool "Ext4 Encryption"
depends on EXT4_FS
select FS_ENCRYPTION
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
|
