Commit c290ea01 authored by Jan Kara's avatar Jan Kara Committed by Jan Kara

fs: Remove ext3 filesystem driver

The functionality of ext3 is fully supported by ext4 driver. Major
distributions (SUSE, RedHat) already use ext4 driver to handle ext3
filesystems for quite some time. There is some ugliness in mm resulting
from jbd cleaning buffers in a dirty page without cleaning page dirty
bit and also support for buffer bouncing in the block layer when stable
pages are required is there only because of jbd. So let's remove the
ext3 driver. This saves us some 28k lines of duplicated code.
Acked-by: default avatarTheodore Ts'o <>
Signed-off-by: default avatarJan Kara <>
parent 82ff50b2
......@@ -360,8 +360,8 @@ and are copied into the filesystem. If a transaction is incomplete at
the time of the crash, then there is no guarantee of consistency for
the blocks in that transaction so they are discarded (which means any
filesystem changes they represent are also lost).
Check Documentation/filesystems/ext3.txt if you want to read more about
ext3 and journaling.
Check Documentation/filesystems/ext4.txt if you want to read more about
ext4 and journaling.
......@@ -6,210 +6,7 @@ Ext3 was originally released in September 1999. Written by Stephen Tweedie
for the 2.2 branch, and ported to 2.4 kernels by Peter Braam, Andreas Dilger,
Andrew Morton, Alexander Viro, Ted Ts'o and Stephen Tweedie.
Ext3 is the ext2 filesystem enhanced with journalling capabilities.
Ext3 is the ext2 filesystem enhanced with journalling capabilities. The
filesystem is a subset of ext4 filesystem so use ext4 driver for accessing
ext3 filesystems.
When mounting an ext3 filesystem, the following option are accepted:
(*) == default
ro Mount filesystem read only. Note that ext3 will replay
the journal (and thus write to the partition) even when
mounted "read only". Mount options "ro,noload" can be
used to prevent writes to the filesystem.
journal=update Update the ext3 file system's journal to the current
journal=inum When a journal already exists, this option is ignored.
Otherwise, it specifies the number of the inode which
will represent the ext3 file system's journal file.
journal_dev=devnum When the external journal device's major/minor numbers
have changed, these options allow the user to specify
the new journal location. The journal device is
identified through either its new major/minor numbers
encoded in devnum, or via a path to the device.
norecovery Don't load the journal on mounting. Note that this forces
noload mount of inconsistent filesystem, which can lead to
various problems.
data=journal All data are committed into the journal prior to being
written into the main file system.
data=ordered (*) All data are forced directly out to the main file
system prior to its metadata being committed to the
data=writeback Data ordering is not preserved, data may be written
into the main file system after its metadata has been
committed to the journal.
commit=nrsec (*) Ext3 can be told to sync all its data and metadata
every 'nrsec' seconds. The default value is 5 seconds.
This means that if you lose your power, you will lose
as much as the latest 5 seconds of work (your
filesystem will not be damaged though, thanks to the
journaling). This default value (or any low value)
will hurt performance, but it's good for data-safety.
Setting it to 0 will have the same effect as leaving
it at the default (5 seconds).
Setting it to very large values will improve
barrier=<0|1(*)> This enables/disables the use of write barriers in
barrier (*) the jbd code. barrier=0 disables, barrier=1 enables.
nobarrier This also requires an IO stack which can support
barriers, and if jbd gets an error on a barrier
write, it will disable again with a warning.
Write barriers enforce proper on-disk ordering
of journal commits, making volatile disk write caches
safe to use, at some performance penalty. If
your disks are battery-backed in one way or another,
disabling barriers may safely improve performance.
The mount options "barrier" and "nobarrier" can
also be used to enable or disable barriers, for
consistency with other ext3 mount options.
user_xattr Enables Extended User Attributes. Additionally, you
need to have extended attribute support enabled in the
kernel configuration (CONFIG_EXT3_FS_XATTR). See the
attr(5) manual page and to
learn more about extended attributes.
nouser_xattr Disables Extended User Attributes.
acl Enables POSIX Access Control Lists support.
Additionally, you need to have ACL support enabled in
the kernel configuration (CONFIG_EXT3_FS_POSIX_ACL).
See the acl(5) manual page and
for more information.
noacl This option disables POSIX Access Control List
bsddf (*) Make 'df' act like BSD.
minixdf Make 'df' act like Minix.
check=none Don't do extra checking of bitmaps on mount.
debug Extra debugging information is sent to syslog.
errors=remount-ro Remount the filesystem read-only on an error.
errors=continue Keep going on a filesystem error.
errors=panic Panic and halt the machine if an error occurs.
(These mount options override the errors behavior
specified in the superblock, which can be
configured using tune2fs.)
data_err=ignore(*) Just print an error message if an error occurs
in a file data buffer in ordered mode.
data_err=abort Abort the journal if an error occurs in a file
data buffer in ordered mode.
grpid Give objects the same group ID as their creator.
nogrpid (*) New objects have the group ID of their creator.
resgid=n The group ID which may use the reserved blocks.
resuid=n The user ID which may use the reserved blocks.
sb=n Use alternate superblock at this location.
quota These options are ignored by the filesystem. They
noquota are used only by quota tools to recognize volumes
grpquota where quota should be turned on. See documentation
usrquota in the quota-tools package for more details
jqfmt=<quota type> These options tell filesystem details about quota
usrjquota=<file> so that quota information can be properly updated
grpjquota=<file> during journal replay. They replace the above
quota options. See documentation in the quota-tools
package for more details
Ext3 shares all disk implementation with the ext2 filesystem, and adds
transactions capabilities to ext2. Journaling is done by the Journaling Block
Device layer.
Journaling Block Device layer
The Journaling Block Device layer (JBD) isn't ext3 specific. It was designed
to add journaling capabilities to a block device. The ext3 filesystem code
will inform the JBD of modifications it is performing (called a transaction).
The journal supports the transactions start and stop, and in case of a crash,
the journal can replay the transactions to quickly put the partition back into
a consistent state.
Handles represent a single atomic update to a filesystem. JBD can handle an
external journal on a block device.
Data Mode
There are 3 different data modes:
* writeback mode
In data=writeback mode, ext3 does not journal data at all. This mode provides
a similar level of journaling as that of XFS, JFS, and ReiserFS in its default
mode - metadata journaling. A crash+recovery can cause incorrect data to
appear in files which were written shortly before the crash. This mode will
typically provide the best ext3 performance.
* ordered mode
In data=ordered mode, ext3 only officially journals metadata, but it logically
groups metadata and data blocks into a single unit called a transaction. When
it's time to write the new metadata out to disk, the associated data blocks
are written first. In general, this mode performs slightly slower than
writeback but significantly faster than journal mode.
* journal mode
data=journal mode provides full data and metadata journaling. All new data is
written to the journal first, and then to its final location.
In the event of a crash, the journal can be replayed, bringing both data and
metadata into a consistent state. This mode is the slowest except when data
needs to be read from and written to disk at the same time where it
outperforms all other modes.
Ext2 partitions can be easily convert to ext3, with `tune2fs -j <dev>`.
Ext3 is fully compatible with Ext2. Ext3 partitions can easily be mounted as
External Tools
See manual pages to learn more.
tune2fs: create a ext3 journal on a ext2 partition with the -j flag.
mke2fs: create a ext3 partition with the -j flag.
debugfs: ext2 and ext3 file system debugger.
ext2online: online (mounted) ext2 and ext3 filesystem resizer
kernel source: <file:fs/ext3/>
useful links:
......@@ -769,7 +769,7 @@ struct address_space_operations {
to stall to allow flushers a chance to complete some IO. Ordinarily
it can use PageDirty and PageWriteback but some filesystems have
more complex state (unstable pages in NFS prevent reclaim) or
do not set those flags due to locking problems (jbd). This callback
do not set those flags due to locking problems. This callback
allows a filesystem to indicate to the VM if a page should be
treated as dirty or writeback for the purposes of stalling.
......@@ -4059,15 +4059,6 @@ F: Documentation/filesystems/ext2.txt
F: fs/ext2/
F: include/linux/ext2*
M: Jan Kara <>
M: Andrew Morton <>
M: Andreas Dilger <>
S: Maintained
F: Documentation/filesystems/ext3.txt
F: fs/ext3/
M: "Theodore Ts'o" <>
M: Andreas Dilger <>
......@@ -5751,16 +5742,9 @@ S: Maintained
F: fs/jffs2/
F: include/uapi/linux/jffs2.h
M: Andrew Morton <>
M: Jan Kara <>
S: Maintained
F: fs/jbd/
F: include/linux/jbd.h
M: "Theodore Ts'o" <>
M: Jan Kara <>
S: Maintained
F: fs/jbd2/
......@@ -11,18 +11,15 @@ config DCACHE_WORD_ACCESS
source "fs/ext2/Kconfig"
source "fs/ext3/Kconfig"
source "fs/ext4/Kconfig"
source "fs/jbd/Kconfig"
source "fs/jbd2/Kconfig"
# Meta block cache for Extended Attributes (ext2/ext3/ext4)
default y if EXT2_FS=y && EXT2_FS_XATTR
default y if EXT3_FS=y && EXT3_FS_XATTR
default y if EXT4_FS=y
default m if EXT2_FS_XATTR || EXT3_FS_XATTR || EXT4_FS
default m if EXT2_FS_XATTR || EXT4_FS
source "fs/reiserfs/Kconfig"
source "fs/jfs/Kconfig"
......@@ -62,12 +62,10 @@ obj-$(CONFIG_DLM) += dlm/
# Do not add any filesystems before this line
obj-$(CONFIG_FSCACHE) += fscache/
obj-$(CONFIG_REISERFS_FS) += reiserfs/
obj-$(CONFIG_EXT3_FS) += ext3/ # Before ext2 so root fs can be ext3
obj-$(CONFIG_EXT2_FS) += ext2/
# We place ext4 after ext2 so plain ext2 root fs's are mounted using ext2
# unless explicitly requested by rootfstype
obj-$(CONFIG_EXT4_FS) += ext4/
obj-$(CONFIG_JBD) += jbd/
obj-$(CONFIG_JBD2) += jbd2/
obj-$(CONFIG_CRAMFS) += cramfs/
obj-$(CONFIG_SQUASHFS) += squashfs/
config EXT3_FS
tristate "Ext3 journalling file system support"
select JBD
This is the journalling version of the Second extended file system
(often called ext3), the de facto standard Linux file system
(method to organize files on a storage device) for hard disks.
The journalling code included in this driver means you do not have
to run e2fsck (file system checker) on your file systems after a
crash. The journal keeps track of any changes that were being made
at the time the system crashed, and can ensure that your file system
is consistent without the need for a lengthy check.
Other than adding the journal to the file system, the on-disk format
of ext3 is identical to ext2. It is possible to freely switch
between using the ext3 driver and the ext2 driver, as long as the
file system has been cleanly unmounted, or e2fsck is run on the file
To add a journal on an existing ext2 file system or change the
behavior of ext3 file systems, you can use the tune2fs utility ("man
tune2fs"). To modify attributes of files and directories on ext3
file systems, use chattr ("man chattr"). You need to be using
e2fsprogs version 1.20 or later in order to create ext3 journals
(available at <>).
To compile this file system support as a module, choose M here: the
module will be called ext3.
bool "Default to 'data=ordered' in ext3"
depends on EXT3_FS
default y
The journal mode options for ext3 have different tradeoffs
between when data is guaranteed to be on disk and
performance. The use of "data=writeback" can cause
unwritten data to appear in files after an system crash or
power failure, which can be a security issue. However,
"data=ordered" mode can also result in major performance
problems, including seconds-long delays before an fsync()
call returns. For details, see:
If you have been historically happy with ext3's performance,
data=ordered mode will be a safe choice and you should
answer 'y' here. If you understand the reliability and data
privacy issues of data=writeback and are willing to make
that trade off, answer 'n'.
config EXT3_FS_XATTR
bool "Ext3 extended attributes"
depends on EXT3_FS
default y
Extended attributes are name:value pairs associated with inodes by
the kernel or by users (see the attr(5) manual page, or visit
<> for details).
If unsure, say N.
You need this for POSIX ACL support on ext3.
bool "Ext3 POSIX Access Control Lists"
depends on EXT3_FS_XATTR
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 <>.
If you don't know what Access Control Lists are, say N
bool "Ext3 Security Labels"
depends on EXT3_FS_XATTR
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 ext3 filesystem.
If you are not using a security module that requires using
extended attributes for file security labels, say N.
# Makefile for the linux ext3-filesystem routines.
obj-$(CONFIG_EXT3_FS) += ext3.o
ext3-y := balloc.o bitmap.o dir.o file.o fsync.o ialloc.o inode.o \
ioctl.o namei.o super.o symlink.o hash.o resize.o ext3_jbd.o
ext3-$(CONFIG_EXT3_FS_XATTR) += xattr.o xattr_user.o xattr_trusted.o
ext3-$(CONFIG_EXT3_FS_POSIX_ACL) += acl.o
ext3-$(CONFIG_EXT3_FS_SECURITY) += xattr_security.o
* linux/fs/ext3/acl.c
* Copyright (C) 2001-2003 Andreas Gruenbacher, <>
#include "ext3.h"
#include "xattr.h"
#include "acl.h"
* Convert from filesystem to in-memory representation.
static struct posix_acl *
ext3_acl_from_disk(const void *value, size_t size)
const char *end = (char *)value + size;
int n, count;
struct posix_acl *acl;
if (!value)
return NULL;
if (size < sizeof(ext3_acl_header))
return ERR_PTR(-EINVAL);
if (((ext3_acl_header *)value)->a_version !=
return ERR_PTR(-EINVAL);
value = (char *)value + sizeof(ext3_acl_header);
count = ext3_acl_count(size);
if (count < 0)
return ERR_PTR(-EINVAL);
if (count == 0)
return NULL;
acl = posix_acl_alloc(count, GFP_NOFS);
if (!acl)
return ERR_PTR(-ENOMEM);
for (n=0; n < count; n++) {
ext3_acl_entry *entry =
(ext3_acl_entry *)value;
if ((char *)value + sizeof(ext3_acl_entry_short) > end)
goto fail;
acl->a_entries[n].e_tag = le16_to_cpu(entry->e_tag);
acl->a_entries[n].e_perm = le16_to_cpu(entry->e_perm);
switch(acl->a_entries[n].e_tag) {
case ACL_MASK:
value = (char *)value +
case ACL_USER:
value = (char *)value + sizeof(ext3_acl_entry);
if ((char *)value > end)
goto fail;
acl->a_entries[n].e_uid =
value = (char *)value + sizeof(ext3_acl_entry);
if ((char *)value > end)
goto fail;
acl->a_entries[n].e_gid =
goto fail;
if (value != end)
goto fail;
return acl;
return ERR_PTR(-EINVAL);
* Convert from in-memory to filesystem representation.
static void *
ext3_acl_to_disk(const struct posix_acl *acl, size_t *size)
ext3_acl_header *ext_acl;
char *e;
size_t n;
*size = ext3_acl_size(acl->a_count);
ext_acl = kmalloc(sizeof(ext3_acl_header) + acl->a_count *
sizeof(ext3_acl_entry), GFP_NOFS);
if (!ext_acl)
return ERR_PTR(-ENOMEM);
ext_acl->a_version = cpu_to_le32(EXT3_ACL_VERSION);
e = (char *)ext_acl + sizeof(ext3_acl_header);
for (n=0; n < acl->a_count; n++) {
const struct posix_acl_entry *acl_e = &acl->a_entries[n];
ext3_acl_entry *entry = (ext3_acl_entry *)e;
entry->e_tag = cpu_to_le16(acl_e->e_tag);
entry->e_perm = cpu_to_le16(acl_e->e_perm);
switch(acl_e->e_tag) {
case ACL_USER:
entry->e_id = cpu_to_le32(
from_kuid(&init_user_ns, acl_e->e_uid));
e += sizeof(ext3_acl_entry);
entry->e_id = cpu_to_le32(
from_kgid(&init_user_ns, acl_e->e_gid));
e += sizeof(ext3_acl_entry);
case ACL_MASK:
e += sizeof(ext3_acl_entry_short);
goto fail;
return (char *)ext_acl;
return ERR_PTR(-EINVAL);
* Inode operation get_posix_acl().
* inode->i_mutex: don't care
struct posix_acl *
ext3_get_acl(struct inode *inode, int type)
int name_index;
char *value = NULL;
struct posix_acl *acl;
int retval;
switch (type) {
retval = ext3_xattr_get(inode, name_index, "", NULL, 0);
if (retval > 0) {
value = kmalloc(retval, GFP_NOFS);
if (!value)
return ERR_PTR(-ENOMEM);
retval = ext3_xattr_get(inode, name_index, "", value, retval);
if (retval > 0)
acl = ext3_acl_from_disk(value, retval);
else if (retval == -ENODATA || retval == -ENOSYS)
acl = NULL;
acl = ERR_PTR(retval);
if (!IS_ERR(acl))
set_cached_acl(inode, type, acl);
return acl;
* Set the access or default ACL of an inode.
* inode->i_mutex: down unless called from ext3_new_inode
static int
__ext3_set_acl(handle_t *handle, struct inode *inode, int type,
struct posix_acl *acl)
int name_index;
void *value = NULL;
size_t size = 0;
int error;
switch(type) {
if (acl) {
error = posix_acl_equiv_mode(acl, &inode->i_mode);
if (error < 0)
return error;
else {
inode->i_ctime = CURRENT_TIME_SEC;
ext3_mark_inode_dirty(handle, inode);
if (error == 0)
acl = NULL;
if (!S_ISDIR(inode->i_mode))
return acl ? -EACCES : 0;
return -EINVAL;
if (acl) {
value = ext3_acl_to_disk(acl, &size);
if (IS_ERR(value))
return (int)PTR_ERR(value);
error = ext3_xattr_set_handle(handle, inode, name_index, "",
value, size, 0);
if (!error)
set_cached_acl(inode, type, acl);
return error;
ext3_set_acl(struct inode *inode, struct posix_acl *acl, int type)
handle_t *handle;
int error, retries = 0;
handle = ext3_journal_start(inode, EXT3_DATA_TRANS_BLOCKS(inode->i_sb));
if (IS_ERR(handle))
return PTR_ERR(handle);
error = __ext3_set_acl(handle, inode, type, acl);
if (error == -ENOSPC && ext3_should_retry_alloc(inode->i_sb, &retries))
goto retry;
return error;
* Initialize the ACLs of a new inode. Called from ext3_new_inode.
* dir->i_mutex: down
* inode->i_mutex: up (access to inode is still exclusive)
ext3_init_acl(handle_t *handle, struct inode *inode, struct inode *dir)
struct posix_acl *default_acl, *acl;
int error;
error = posix_acl_create(dir, &inode->i_mode, &default_acl, &acl);
if (error)
return error;
if (default_acl) {
error = __ext3_set_acl(handle, inode, ACL_TYPE_DEFAULT,
if (acl) {
if (!error)
error = __ext3_set_acl(handle, inode, ACL_TYPE_ACCESS,
return error;
File: fs/ext3/acl.h
(C) 2001 Andreas Gruenbacher, <>
#include <linux/posix_acl_xattr.h>
#define EXT3_ACL_VERSION 0x0001
typedef struct {
__le16 e_tag;
__le16 e_perm;
__le32 e_id;
} ext3_acl_entry;
typedef struct {
__le16 e_tag;
__le16 e_perm;
} ext3_acl_entry_short;
typedef struct {
__le32 a_version;
} ext3_acl_header;
static inline size_t ext3_acl_size(int count)
if (count <= 4) {
return sizeof(ext3_acl_header) +
count * sizeof(ext3_acl_entry_short);
} else {
return sizeof(ext3_acl_header) +
4 * sizeof(ext3_acl_entry_short) +
(count - 4) * sizeof(ext3_acl_entry);
static inline int ext3_acl_count(size_t size)
ssize_t s;
size -= sizeof(ext3_acl_header);
s = size - 4 * sizeof(ext3_acl_entry_short);
if (s < 0) {
if (size % sizeof(ext3_acl_entry_short))
return -1;
return size / sizeof(ext3_acl_entry_short);
} else {
if (s % sizeof(ext3_acl_entry))
return -1;
return s / sizeof(ext3_acl_entry) + 4;
/* acl.c */
extern struct posix_acl *ext3_get_acl(struct inode *inode, int type);