1c290ea01SJan Kara# Ext3 configs are here for backward compatibility with old configs which may 2c290ea01SJan Kara# have EXT3_FS set but not EXT4_FS set and thus would result in non-bootable 3c290ea01SJan Kara# kernels after the removal of ext3 driver. 4c290ea01SJan Karaconfig EXT3_FS 5c290ea01SJan Kara tristate "The Extended 3 (ext3) filesystem" 6c290ea01SJan Kara # These must match EXT4_FS selects... 7c290ea01SJan Kara select EXT4_FS 8c290ea01SJan Kara select JBD2 9c290ea01SJan Kara select CRC16 10c290ea01SJan Kara select CRYPTO 11c290ea01SJan Kara select CRYPTO_CRC32C 12c290ea01SJan Kara help 13c290ea01SJan Kara This config option is here only for backward compatibility. ext3 14c290ea01SJan Kara filesystem is now handled by the ext4 driver. 15c290ea01SJan Kara 16c290ea01SJan Karaconfig EXT3_FS_POSIX_ACL 17c290ea01SJan Kara bool "Ext3 POSIX Access Control Lists" 18c290ea01SJan Kara depends on EXT3_FS 19c290ea01SJan Kara select EXT4_FS_POSIX_ACL 20c290ea01SJan Kara select FS_POSIX_ACL 21c290ea01SJan Kara help 22c290ea01SJan Kara This config option is here only for backward compatibility. ext3 23c290ea01SJan Kara filesystem is now handled by the ext4 driver. 24c290ea01SJan Kara 25c290ea01SJan Karaconfig EXT3_FS_SECURITY 26c290ea01SJan Kara bool "Ext3 Security Labels" 27c290ea01SJan Kara depends on EXT3_FS 28c290ea01SJan Kara select EXT4_FS_SECURITY 29c290ea01SJan Kara help 30c290ea01SJan Kara This config option is here only for backward compatibility. ext3 31c290ea01SJan Kara filesystem is now handled by the ext4 driver. 32c290ea01SJan Kara 336da0b38fSAlexey Dobriyanconfig EXT4_FS 346da0b38fSAlexey Dobriyan tristate "The Extended 4 (ext4) filesystem" 35c290ea01SJan Kara # Please update EXT3_FS selects when changing these 366da0b38fSAlexey Dobriyan select JBD2 376da0b38fSAlexey Dobriyan select CRC16 380441984aSDarrick J. Wong select CRYPTO 390441984aSDarrick J. Wong select CRYPTO_CRC32C 406da0b38fSAlexey Dobriyan help 416da0b38fSAlexey Dobriyan This is the next generation of the ext3 filesystem. 426da0b38fSAlexey Dobriyan 436da0b38fSAlexey Dobriyan Unlike the change from ext2 filesystem to ext3 filesystem, 446da0b38fSAlexey Dobriyan the on-disk format of ext4 is not forwards compatible with 456da0b38fSAlexey Dobriyan ext3; it is based on extent maps and it supports 48-bit 466da0b38fSAlexey Dobriyan physical block numbers. The ext4 filesystem also supports delayed 476da0b38fSAlexey Dobriyan allocation, persistent preallocation, high resolution time stamps, 486da0b38fSAlexey Dobriyan and a number of other features to improve performance and speed 496da0b38fSAlexey Dobriyan up fsck time. For more information, please see the web pages at 506da0b38fSAlexey Dobriyan http://ext4.wiki.kernel.org. 516da0b38fSAlexey Dobriyan 52c8962f4bSJan Kara The ext4 filesystem supports mounting an ext3 filesystem; while there 53c8962f4bSJan Kara are some performance gains from the delayed allocation and inode 54c8962f4bSJan Kara table readahead, the best performance gains require enabling ext4 55c8962f4bSJan Kara features in the filesystem using tune2fs, or formatting a new 56c8962f4bSJan Kara filesystem as an ext4 filesystem initially. Without explicit enabling 57c8962f4bSJan Kara of ext4 features, the on disk filesystem format stays fully backward 58c8962f4bSJan Kara compatible. 596da0b38fSAlexey Dobriyan 606da0b38fSAlexey Dobriyan To compile this file system support as a module, choose M here. The 616da0b38fSAlexey Dobriyan module will be called ext4. 626da0b38fSAlexey Dobriyan 636da0b38fSAlexey Dobriyan If unsure, say N. 646da0b38fSAlexey Dobriyan 65c290ea01SJan Karaconfig EXT4_USE_FOR_EXT2 66d4eb6deeSJean Delvare bool "Use ext4 for ext2 file systems" 6784c66473SDavid Howells depends on EXT4_FS 68c290ea01SJan Kara depends on EXT2_FS=n 6924b58424STheodore Ts'o default y 7024b58424STheodore Ts'o help 71c290ea01SJan Kara Allow the ext4 file system driver code to be used for ext2 72c290ea01SJan Kara file system mounts. This allows users to reduce their 7324b58424STheodore Ts'o compiled kernel size by using one file system driver for 7424b58424STheodore Ts'o ext2, ext3, and ext4 file systems. 7524b58424STheodore Ts'o 766da0b38fSAlexey Dobriyanconfig EXT4_FS_POSIX_ACL 776da0b38fSAlexey Dobriyan bool "Ext4 POSIX Access Control Lists" 7896465efeSValerie Aurora depends on EXT4_FS 796da0b38fSAlexey Dobriyan select FS_POSIX_ACL 806da0b38fSAlexey Dobriyan help 816da0b38fSAlexey Dobriyan POSIX Access Control Lists (ACLs) support permissions for users and 826da0b38fSAlexey Dobriyan groups beyond the owner/group/world scheme. 836da0b38fSAlexey Dobriyan 846da0b38fSAlexey Dobriyan To learn more about Access Control Lists, visit the POSIX ACLs for 856da0b38fSAlexey Dobriyan Linux website <http://acl.bestbits.at/>. 866da0b38fSAlexey Dobriyan 876da0b38fSAlexey Dobriyan If you don't know what Access Control Lists are, say N 886da0b38fSAlexey Dobriyan 896da0b38fSAlexey Dobriyanconfig EXT4_FS_SECURITY 906da0b38fSAlexey Dobriyan bool "Ext4 Security Labels" 9196465efeSValerie Aurora depends on EXT4_FS 926da0b38fSAlexey Dobriyan help 936da0b38fSAlexey Dobriyan Security labels support alternative access control models 946da0b38fSAlexey Dobriyan implemented by security modules like SELinux. This option 956da0b38fSAlexey Dobriyan enables an extended attribute handler for file security 966da0b38fSAlexey Dobriyan labels in the ext4 filesystem. 976da0b38fSAlexey Dobriyan 986da0b38fSAlexey Dobriyan If you are not using a security module that requires using 996da0b38fSAlexey Dobriyan extended attributes for file security labels, say N. 1006ba495e9STheodore Ts'o 101fb63e548SHerbert Xuconfig EXT4_ENCRYPTION 102fb63e548SHerbert Xu tristate "Ext4 Encryption" 103b17655fbSTheodore Ts'o depends on EXT4_FS 104b17655fbSTheodore Ts'o select CRYPTO_AES 105b17655fbSTheodore Ts'o select CRYPTO_CBC 106b17655fbSTheodore Ts'o select CRYPTO_ECB 107b17655fbSTheodore Ts'o select CRYPTO_XTS 108b17655fbSTheodore Ts'o select CRYPTO_CTS 10971dea01eSTheodore Ts'o select CRYPTO_CTR 110b17655fbSTheodore Ts'o select CRYPTO_SHA256 111b17655fbSTheodore Ts'o select KEYS 112b17655fbSTheodore Ts'o select ENCRYPTED_KEYS 113b17655fbSTheodore Ts'o help 114b17655fbSTheodore Ts'o Enable encryption of ext4 files and directories. This 115b17655fbSTheodore Ts'o feature is similar to ecryptfs, but it is more memory 116b17655fbSTheodore Ts'o efficient since it avoids caching the encrypted and 117b17655fbSTheodore Ts'o decrypted pages in the page cache. 118b17655fbSTheodore Ts'o 119fb63e548SHerbert Xuconfig EXT4_FS_ENCRYPTION 120fb63e548SHerbert Xu bool 121fb63e548SHerbert Xu default y 122fb63e548SHerbert Xu depends on EXT4_ENCRYPTION 123fb63e548SHerbert Xu 1246ba495e9STheodore Ts'oconfig EXT4_DEBUG 1256ba495e9STheodore Ts'o bool "EXT4 debugging support" 1266ba495e9STheodore Ts'o depends on EXT4_FS 1276ba495e9STheodore Ts'o help 1286ba495e9STheodore Ts'o Enables run-time debugging support for the ext4 filesystem. 1296ba495e9STheodore Ts'o 1306ba495e9STheodore Ts'o If you select Y here, then you will be able to turn on debugging 1317f3e3c7cSTheodore Ts'o with a command such as: 1327f3e3c7cSTheodore Ts'o echo 1 > /sys/module/ext4/parameters/mballoc_debug 133