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. 4config 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 16config 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 25config 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 33config EXT4_FS 34 tristate "The Extended 4 (ext4) filesystem" 35 # Please update EXT3_FS selects when changing these 36 select JBD2 37 select CRC16 38 select CRYPTO 39 select CRYPTO_CRC32C 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 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. 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 65config EXT4_USE_FOR_EXT2 66 bool "Use ext4 for ext2 file systems" 67 depends on EXT4_FS 68 depends on EXT2_FS=n 69 default y 70 help 71 Allow the ext4 file system driver code to be used for ext2 72 file system mounts. This allows users to reduce their 73 compiled kernel size by using one file system driver for 74 ext2, ext3, and ext4 file systems. 75 76config EXT4_FS_POSIX_ACL 77 bool "Ext4 POSIX Access Control Lists" 78 depends on EXT4_FS 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 89config EXT4_FS_SECURITY 90 bool "Ext4 Security Labels" 91 depends on EXT4_FS 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. 100 101config EXT4_ENCRYPTION 102 bool "Ext4 Encryption" 103 depends on EXT4_FS 104 select FS_ENCRYPTION 105 help 106 Enable encryption of ext4 files and directories. This 107 feature is similar to ecryptfs, but it is more memory 108 efficient since it avoids caching the encrypted and 109 decrypted pages in the page cache. 110 111config EXT4_FS_ENCRYPTION 112 bool 113 default y 114 depends on EXT4_ENCRYPTION 115 116config EXT4_DEBUG 117 bool "EXT4 debugging support" 118 depends on EXT4_FS 119 help 120 Enables run-time debugging support for the ext4 filesystem. 121 122 If you select Y here, then you will be able to turn on debugging 123 with a command such as: 124 echo 1 > /sys/module/ext4/parameters/mballoc_debug 125