| config EXT4_FS |
| tristate "The Extended 4 (ext4) filesystem" |
| select JBD2 |
| select CRC16 |
| 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 will support mounting an ext3 |
| filesystem; while there will be some performance gains from |
| the delayed allocation and inode table readahead, the best |
| performance gains will require enabling ext4 features in the |
| filesystem, or formating a new filesystem as an ext4 |
| filesystem initially. |
| |
| To compile this file system support as a module, choose M here. The |
| module will be called ext4. |
| |
| If unsure, say N. |
| |
| config EXT4DEV_COMPAT |
| bool "Enable ext4dev compatibility" |
| depends on EXT4_FS |
| help |
| Starting with 2.6.28, the name of the ext4 filesystem was |
| renamed from ext4dev to ext4. Unfortunately there are some |
| legacy userspace programs (such as klibc's fstype) have |
| "ext4dev" hardcoded. |
| |
| To enable backwards compatibility so that systems that are |
| still expecting to mount ext4 filesystems using ext4dev, |
| chose Y here. This feature will go away by 2.6.31, so |
| please arrange to get your userspace programs fixed! |
| |
| config EXT4_FS_XATTR |
| bool "Ext4 extended attributes" |
| depends on EXT4_FS |
| default y |
| help |
| Extended attributes are name:value pairs associated with inodes by |
| the kernel or by users (see the attr(5) manual page, or visit |
| <http://acl.bestbits.at/> for details). |
| |
| If unsure, say N. |
| |
| You need this for POSIX ACL support on ext4. |
| |
| config EXT4_FS_POSIX_ACL |
| bool "Ext4 POSIX Access Control Lists" |
| depends on EXT4_FS_XATTR |
| 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_XATTR |
| 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. |