projects / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 6da0b38f AD |
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 | ||
| bbae8bcc | 31 | config EXT3_DEFAULTS_TO_ORDERED |
| 6d418076 | 32 | bool "Default to 'data=ordered' in ext3" |
| bbae8bcc LT |
33 | depends on EXT3_FS |
| 34 | help | |
| 6d418076 TT |
35 | The journal mode options for ext3 have different tradeoffs |
| 36 | between when data is guaranteed to be on disk and | |
| 37 | performance. The use of "data=writeback" can cause | |
| 38 | unwritten data to appear in files after an system crash or | |
| 39 | power failure, which can be a security issue. However, | |
| 40 | "data=ordered" mode can also result in major performance | |
| 41 | problems, including seconds-long delays before an fsync() | |
| 42 | call returns. For details, see: | |
| 43 | ||
| 44 | http://ext4.wiki.kernel.org/index.php/Ext3_data_mode_tradeoffs | |
| 45 | ||
| 46 | If you have been historically happy with ext3's performance, | |
| 47 | data=ordered mode will be a safe choice and you should | |
| 48 | answer 'y' here. If you understand the reliability and data | |
| 49 | privacy issues of data=writeback and are willing to make | |
| 50 | that trade off, answer 'n'. | |
| bbae8bcc | 51 | |
| 6da0b38f AD |
52 | config EXT3_FS_XATTR |
| 53 | bool "Ext3 extended attributes" | |
| 54 | depends on EXT3_FS | |
| 55 | default y | |
| 56 | help | |
| 57 | Extended attributes are name:value pairs associated with inodes by | |
| 58 | the kernel or by users (see the attr(5) manual page, or visit | |
| 59 | <http://acl.bestbits.at/> for details). | |
| 60 | ||
| 61 | If unsure, say N. | |
| 62 | ||
| 63 | You need this for POSIX ACL support on ext3. | |
| 64 | ||
| 65 | config EXT3_FS_POSIX_ACL | |
| 66 | bool "Ext3 POSIX Access Control Lists" | |
| 67 | depends on EXT3_FS_XATTR | |
| 68 | select FS_POSIX_ACL | |
| 69 | help | |
| 70 | Posix Access Control Lists (ACLs) support permissions for users and | |
| 71 | groups beyond the owner/group/world scheme. | |
| 72 | ||
| 73 | To learn more about Access Control Lists, visit the Posix ACLs for | |
| 74 | Linux website <http://acl.bestbits.at/>. | |
| 75 | ||
| 76 | If you don't know what Access Control Lists are, say N | |
| 77 | ||
| 78 | config EXT3_FS_SECURITY | |
| 79 | bool "Ext3 Security Labels" | |
| 80 | depends on EXT3_FS_XATTR | |
| 81 | help | |
| 82 | Security labels support alternative access control models | |
| 83 | implemented by security modules like SELinux. This option | |
| 84 | enables an extended attribute handler for file security | |
| 85 | labels in the ext3 filesystem. | |
| 86 | ||
| 87 | If you are not using a security module that requires using | |
| 88 | extended attributes for file security labels, say N. |