Alexey Dobriyan | 6da0b38 | 2008-10-20 22:28:45 +0400 | [diff] [blame] | 1 | config EXT3_FS |
| 2 | tristate "Ext3 journalling file system support" |
| 3 | select JBD |
| 4 | help |
| 5 | This is the journalling version of the Second extended file system |
| 6 | (often called ext3), the de facto standard Linux file system |
| 7 | (method to organize files on a storage device) for hard disks. |
| 8 | |
| 9 | The journalling code included in this driver means you do not have |
| 10 | to run e2fsck (file system checker) on your file systems after a |
| 11 | crash. The journal keeps track of any changes that were being made |
| 12 | at the time the system crashed, and can ensure that your file system |
| 13 | is consistent without the need for a lengthy check. |
| 14 | |
| 15 | Other than adding the journal to the file system, the on-disk format |
| 16 | of ext3 is identical to ext2. It is possible to freely switch |
| 17 | between using the ext3 driver and the ext2 driver, as long as the |
| 18 | file system has been cleanly unmounted, or e2fsck is run on the file |
| 19 | system. |
| 20 | |
| 21 | To add a journal on an existing ext2 file system or change the |
| 22 | behavior of ext3 file systems, you can use the tune2fs utility ("man |
| 23 | tune2fs"). To modify attributes of files and directories on ext3 |
| 24 | file systems, use chattr ("man chattr"). You need to be using |
| 25 | e2fsprogs version 1.20 or later in order to create ext3 journals |
| 26 | (available at <http://sourceforge.net/projects/e2fsprogs/>). |
| 27 | |
| 28 | To compile this file system support as a module, choose M here: the |
| 29 | module will be called ext3. |
| 30 | |
Linus Torvalds | bbae8bc | 2009-04-06 17:16:47 -0700 | [diff] [blame] | 31 | config EXT3_DEFAULTS_TO_ORDERED |
Theodore Ts'o | 6d41807 | 2009-08-10 16:03:43 -0400 | [diff] [blame] | 32 | bool "Default to 'data=ordered' in ext3" |
Linus Torvalds | bbae8bc | 2009-04-06 17:16:47 -0700 | [diff] [blame] | 33 | depends on EXT3_FS |
Dave Chinner | aa32a79 | 2010-07-23 12:49:41 +0200 | [diff] [blame] | 34 | default y |
Linus Torvalds | bbae8bc | 2009-04-06 17:16:47 -0700 | [diff] [blame] | 35 | help |
Theodore Ts'o | 6d41807 | 2009-08-10 16:03:43 -0400 | [diff] [blame] | 36 | The journal mode options for ext3 have different tradeoffs |
| 37 | between when data is guaranteed to be on disk and |
| 38 | performance. The use of "data=writeback" can cause |
| 39 | unwritten data to appear in files after an system crash or |
| 40 | power failure, which can be a security issue. However, |
| 41 | "data=ordered" mode can also result in major performance |
| 42 | problems, including seconds-long delays before an fsync() |
| 43 | call returns. For details, see: |
Linus Torvalds | bbae8bc | 2009-04-06 17:16:47 -0700 | [diff] [blame] | 44 | |
Theodore Ts'o | 6d41807 | 2009-08-10 16:03:43 -0400 | [diff] [blame] | 45 | http://ext4.wiki.kernel.org/index.php/Ext3_data_mode_tradeoffs |
Linus Torvalds | bbae8bc | 2009-04-06 17:16:47 -0700 | [diff] [blame] | 46 | |
Theodore Ts'o | 6d41807 | 2009-08-10 16:03:43 -0400 | [diff] [blame] | 47 | If you have been historically happy with ext3's performance, |
| 48 | data=ordered mode will be a safe choice and you should |
| 49 | answer 'y' here. If you understand the reliability and data |
| 50 | privacy issues of data=writeback and are willing to make |
| 51 | that trade off, answer 'n'. |
Linus Torvalds | bbae8bc | 2009-04-06 17:16:47 -0700 | [diff] [blame] | 52 | |
Alexey Dobriyan | 6da0b38 | 2008-10-20 22:28:45 +0400 | [diff] [blame] | 53 | config EXT3_FS_XATTR |
| 54 | bool "Ext3 extended attributes" |
| 55 | depends on EXT3_FS |
| 56 | default y |
| 57 | help |
| 58 | Extended attributes are name:value pairs associated with inodes by |
| 59 | the kernel or by users (see the attr(5) manual page, or visit |
| 60 | <http://acl.bestbits.at/> for details). |
| 61 | |
| 62 | If unsure, say N. |
| 63 | |
| 64 | You need this for POSIX ACL support on ext3. |
| 65 | |
| 66 | config EXT3_FS_POSIX_ACL |
| 67 | bool "Ext3 POSIX Access Control Lists" |
| 68 | depends on EXT3_FS_XATTR |
| 69 | select FS_POSIX_ACL |
| 70 | help |
| 71 | Posix Access Control Lists (ACLs) support permissions for users and |
| 72 | groups beyond the owner/group/world scheme. |
| 73 | |
| 74 | To learn more about Access Control Lists, visit the Posix ACLs for |
| 75 | Linux website <http://acl.bestbits.at/>. |
| 76 | |
| 77 | If you don't know what Access Control Lists are, say N |
| 78 | |
| 79 | config EXT3_FS_SECURITY |
| 80 | bool "Ext3 Security Labels" |
| 81 | depends on EXT3_FS_XATTR |
| 82 | help |
| 83 | Security labels support alternative access control models |
| 84 | implemented by security modules like SELinux. This option |
| 85 | enables an extended attribute handler for file security |
| 86 | labels in the ext3 filesystem. |
| 87 | |
| 88 | If you are not using a security module that requires using |
| 89 | extended attributes for file security labels, say N. |