This reverts commit d988201ef9.
The problem with this commit is that causes common small file system
configurations to fail. For example:
mke2fs -O flex_bg -b 4096 -I 1024 -F /tmp/tt 79106
mke2fs 1.42.11 (09-Jul-2014)
/tmp/tt: Invalid argument passed to ext2 library while setting
up superblock
This check in ext2fs_initialize() was added to prevent the metadata
from being allocated beyond the end of the filesystem, but it is
also causing a wide range of failures for small filesystems.
We'll address this in a different way, by using a smarter algorithm
for deciding the layout of metadata blocks for the last flex block
group.
Reported-by: Andreas Dilger <andreas.dilger@intel.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
In mke2fs command, if flex_bg count is too large to filesystem blocks
count, unmountable ext4 which has the out of filesystem block offset
is created (Case1). Moreover this large flex_bg count causes an
unintentional metadata layout (bmap-imap-itable-bmap-imap-itable .. in
block group) (Case2).
To fix these issues and keep healthy flex_bg layout, disallow creating
ext4 with obviously large flex_bg count to filesystem blocks count.
Steps to reproduce:
(Case1)
1.
# mke2fs -t ext4 -b 4096 -O ^resize_inode -G $((2**20)) DEV 2130483
2.
# mount -t ext4 DEV MP
mount: wrong fs type, bad option, bad superblock on /dev/sdb4,
missing codepage or helper program, or other error
In some cases useful info is found in syslog - try
dmesg | tail or so
3.
# dumpe2fs DEV
...
Block count: 2130483
...
Flex block group size: 1048576
...
Group 65: (Blocks 2129920-2130482) [INODE_UNINIT]
Checksum 0x4cb3, unused inodes 8080
Block bitmap at 67 (bg #0 + 67), Inode bitmap at 1048643 (bg #32 + 67)
Inode table at 2129979-2130483 (+59)
^^^^^^^ 2130483 is out of FS!
65535 free blocks, 8080 free inodes, 0 directories, 8080 unused inodes
Free blocks:
Free inodes: 525201-533280
(Case2)
1.
# mke2fs -t ext4 -G 2147483648 DEV 3145728
2.
# debugfs -R stats DEV
...
Block count: 786432
...
Flex block group size: 2147483648
...
Group 0: block bitmap at 193, inode bitmap at 194, inode table at 195
...
Group 1: block bitmap at 707, inode bitmap at 708, inode table at 709
...
Group 2: block bitmap at 1221, inode bitmap at 1222, inode table at 1223
...
Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
In practice, it is **extremely** rare for users to try to use more
than the first backup superblock located at the beginning of block
group #1. (i.e., at block number 32768 for file systems with a 4k
block size). This new compat feature restricts the backup superblock
to block group #1 and the last block group in the file system.
Aside from reducing the overhead of the file system by a small number
of blocks, by eliminating the rest of the backup superblocks, it
allows us to have a much more flexible metadata layout. For example,
we can force all of the allocation bitmaps and inode table blocks to
the beginning of the disk, which allows most of the disk to be
exclusively used for contiguous data blocks.
This simplifies taking advantage of certain HDD specific features,
such as Shingled Magnetic Recording (aka Shingled Drives), and the
TCG's OPAL Storage Specification where having a simple mapping between
LBA block ranges and the data blocks used by the file system can make
life much simpler.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The s_desc_size in the superblock specifies the group descriptor
size in bytes, but in various places the EXT4_FEATURE_INCOMPAT_64BIT
flag implies that the descriptor size is EXT2_MIN_DESC_SIZE_64BIT
(64 bytes) instead of checking the actual size. In other places,
the s_desc_size field is used without checking for INCOMPAT_64BIT.
In the case of ext2fs_group_desc() the s_desc_size was being ignored,
and assumed to be sizeof(struct ext4_group_desc), which would result
in garbage for any but the first group descriptor. Similarly, in
ext2fs_group_desc_csum() and print_csum() they assumed that the
maximum group descriptor size was sizeof(struct ext4_group_desc).
Fix these functions to use the actual superblock s_desc_size if
INCOMPAT_64BIT.
Conversely, in ext2fs_swap_group_desc2() s_desc_size was used
without checking for INCOMPAT_64BIT being set.
The e2fsprogs behaviour is different than that of the kernel,
which always checks INCOMPAT_64BIT, and only uses s_desc_size to
determine the offset of group descriptors and what range of bytes
to checksum.
Allow specifying the s_desc_size field at mke2fs time with the
"-E desc_size=NNN" option. Allow a power-of-two s_desc_size
value up to s_blocksize if INCOMPAT_64BIT is specified. This
is not expected to be used by regular users at this time, so it
is not currently documented in the mke2fs usage or man page.
Add m_desc_size_128, f_desc_size_128, and f_desc_bad test cases to
verify mke2fs and e2fsck handling of larger group descriptor sizes.
Signed-off-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
If the user attemps to create a 512MB cluster, we need to adjust the
defaults to avoid a 32-bit overflow of s_blocks_per_group. Also check
to make sure that the caller of ext2fs_initialize() has not given a
value of s_clusters_per_group that would result in an overflow of
s_blocks_per_group.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
Make sure the s_mmp_update_interval super block field is set
from the file system parameters block which is passed into the
ext2fs_initialize() function.
Addresses-Lustre-Bug: LU-1888
Signed-off-by: Gregoire Pichon <gregoire.pichon@bull.net>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
mke2fs -m option can set reserved blocks ratio up to 50%. But if the
last block group is not big enough to support the necessary data
structures, it gets dropped, we have to recalculate the number of
reserved blocks so that the reserved blocks matches the requested
percentage.
It also avoids a problem where if the user specifies a reserved blocks
of 50%, and after the last partial block group was dropped, if the
number of reserved blocks is greater than 50%, e2fsck will complain.
Steps to reproduce:
1. Create a FS which has the overhead for the last BG
and specify 50 % for reserved blocks ratio
# mke2fs -m 50 -t ext4 DEV 1025M
mke2fs 1.42.5 (29-Jul-2012)
warning: 256 blocks unused.
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=0 blocks, Stripe width=0 blocks
656640 inodes, 2621440 blocks
1310848 blocks (50.00%) reserved for the super user
~~~~~~~ <-- Reserved blocks exceed 50% of FS blocks count!
2. e2fsck outputs filesystem corruption
# e2fsck DEV
e2fsck 1.42.5 (29-Jul-2012)
Corruption found in superblock. (r_blocks_count = 1310848).
The superblock could not be read or does not describe a correct ext2
filesystem. If the device is valid and it really contains an ext2
filesystem (and not swap or ufs or something else), then the superblock
is corrupt, and you might try running e2fsck with an alternate superblock:
e2fsck -b 32768 <device>
Signed-off-by: Akira Fujita <a-fujita@rs.jp.ne.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Change the block group algorithm to use the same algorithm as the rest
of the metadata_csum. This mostly involves providing a helper
function to tell if group descriptors should have checksums set or
verified, and modifying the gdt checksum code to use the correct
algorithm.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The following commands:
dd if=/dev/zero of=/tmp/foo count=1 ibs=$(( 256 * 1024 * 1024 ))
mke2fs -N 256 -t ext4 /tmp/foo
... will cause mke2fs to write until it fills the device. The cause
for this is that the explicit request for 256 inodes causes the number
of inodes per block group to be 8. The ext2fs_initialize() function
assumed that all of the reserved inodes would be in the first block
group, which is not true in this case. This caused the number of
uninitialized inodes in the first block group to be negative, which
then resulted in mke2fs trying to zero out a very large number of
blocks. Oops.
Addresses-Sourceforge-Bug: #3528892
Reported-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This can be useful when using mke2fs on loaded servers, since
otherwise mke2fs can dirty a huge amount of memory very quickly,
leading to other applications not being happy at all.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This change causes the max resident memory of mke2fs, as reported by
/usr/bin/time, to drop from 9296k to 5328k when formatting a 25
gig volume.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
If the number of block groups exceeds 2**32, a bad cast would lead to
a bogus "Not enough space to build proposed filesystem while setting
up superblock" failure.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Surely we should be setting s_clusters_per_group, not
s_blocks_per_group, to EXT2_MAX_CLUSTERS_PER_GROUP here.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The DEFS line in MCONFIG had gotten so long that it exceeded 4k, and
this was starting to cause some tools heartburn. It also made "make
V=1" almost useless, since trying to following the individual commands
run by make was lost in the noise of all of the defines.
So fix this by putting the configure-generated defines in lib/config.h
and the directory pathnames to lib/dirpaths.h.
In addition, clean up some vestigal defines in configure.in and in the
Makefiles to further shorten the cc command lines.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The dump program relies on fs->frag_size and the
EXT2_FRAGS_PER_BLOCK() macro. Kind of silly for it to do so, but it's
part of the kludgy way the dump program (which was originally written
for the BSD FFS was ported over to support ext2/3.) Given how it
makes assumptions about the ext2/3/4 file system being similar to the
BSD FFS, it's a bit of a miracle it works for ext4 --- or at least
appears to work...
Addresses-Debian-Bug: #636418
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Treat the s_blocks_count field in the superblock as a free block count
(instead of the number of free clusters) for bigalloc file systems.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The log2 of the ratio of cluster size to block size is far more useful
than just storing the cluster size. So make this change, and then
define basic utility macros: EXT2FS_CLUSTER_RATIO(),
EXT2FS_CLUSTER_MASK(), EXT2FS_B2C(), EXT2FS_C2B(), and
EXT2FS_NUM_B2C().
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
current mkfs.ext4 fails if we tried with the following parameters:
mkfs.ext4 -m 0 -N 16 -O ^has_journal,^resize_inode,^uninit_bg,extent,meta_bg -b 1024 /dev/sdb3
It will cause segfault, but it is caused by another issue. See my
patch "mke2fs: Avoid segmentation fault in
ext2fs_alloc_generic_bmap". And with that patch, the mkfs.ext4 will
fail with the error: /dev/sdb3: Memory allocation failed while setting
up superblock
The reason is that in ext2fs_initialize, we align s_inodes_per_group
to 8, but fails to consider the case that s_inodes_per_group < 8.
So make at least 8 inodes for s_inodes_per_group.
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This adds the superblock fields needed so that dumpe2fs works and the
code points and renames the superblock fields from describing
fragments to clusters.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
User namespace xattrs are generally useful, and I think extN
is the only filesystem requiring a special mount option to
enable them, when xattrs are otherwise available. So this
change sets that mount option into the defaults, via a
mke2fs.conf option.
Note that if xattrs are config'd off, this will lead to a
mostly-harmless:
EXT4-fs (sdc1): (no)user_xattr options not supported
message at mount time...
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The forced fsck often comes at unexpected and inopportune moments,
and even enterprise customers are often caught by surprise when
this happens. Because a filesystem with an error condition will
be marked as requiring fsck anyway, I submit that the time-based
and mount-based checks are not particularly useful, and that
administrators can schedule fscks on their own time, or tune2fs
the enforced intervals if they so choose. This patch disables the
intervals by default, and I've added a new mkfs.conf option to
turn on the old behavior of random, unexpected, time-consuming
fscks at boot time. ;)
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This is needed to enable 64-bit mke2fs to work correctly.
Signed-off-by: Jose R. Santos <jrs@us.ibm.com>
Signed-off-by: Valerie Aurora Henson <vaurora@redhat.com>
Signed-off-by: Nick Dokos <nicholas.dokos@hp.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The top-level COPYING file states that the e2p and ext2fs libraries
are available under the LGPLv2. The files were incorrectly labelled.
Alex Thomas/Luster has been consulted wrt to the ext3_extents.h file;
the rest of the files were primarily authored by Theodore Ts'o.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The ext2fs_bg_flag* functions were confusing.
Currently we have this:
void ext2fs_bg_flags_set(ext2_filsys fs, dgrp_t group, __u16 bg_flags);
void ext2fs_bg_flags_clear(ext2_filsys fs, dgrp_t group,__u16 bg_flags);
(_set (unused) sets exactly bg_flags; _clear clears all and ignores bg_flags)
and these, which can twiddle individual bits in bg_flags:
void ext2fs_bg_flag_set(ext2_filsys fs, dgrp_t group, __u16 bg_flag);
void ext2fs_bg_flag_clear(ext2_filsys fs, dgrp_t group, __u16 bg_flag);
A better interface, after the patch below, is just:
ext2fs_bg_flags_zap(fs, group) /* zeros bg_flags */
ext2fs_bg_flags_set(fs, group, flags) /* adds flags to bg_flags */
ext2fs_bg_flags_clear(fs, group, flags) /* clears flags in bg_flags */
and remove the original ext2fs_bg_flags_set / ext2fs_bg_flags_clear.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Below patch ensures that cleanup is done properly in ext2fs_initialize
from all return paths in case of errors.
Signed-off-by: Manish Katiyar <mkatiyar@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Some bootloaders, like SILO, don't provide sprintf in their limited
bootloader environment. Since the uses in rw_bitmaps.c is only doing
sprintf("foo %s"), it's easy to replace that usage with strcpy/strcat.
Addresses-Sourceforge-Bug: #2049120
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
If we fail doing ext2fs_allocate_block_bitmap() or
ext2fs_allocate_inode_bitmap() we directly goto cleanup and don't free
the memory allocated to buf.
Signed-off-by: "Manish Katiyar" <mkatiyar@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Change the way we allocate bitmaps and inode tables if the FLEX_BG
feature is used at mke2fs time. It places calculates a new offset for
bitmaps and inode table base on the number of groups that the user
wishes to pack together using the new "-G" option. Creating a
filesystem with 64 block groups in a flex group can be done by:
mke2fs -j -I 256 -O flex_bg -G 32 /dev/sdX
Signed-off-by: Jose R. Santos <jrs@us.ibm.com>
Signed-off-by: Valerie Clement <valerie.clement@bull.net>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This fixes some bugs which I introduced recently while revamping the
uninit_bg code. Since mke2fs is no longer calling
ext2fs_set_gdt_csum(), it's important that ext2fs_initialize()
correctly initialize bg_itable_unused for all block group descriptors.
In addition, mke2fs needs to zero out the the reserved inodes based on
the values of bg_itable_unused set by ext2fs_initialize().
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Mke2fs used to have special case, ugly code in
setup_lazy_bg/setup_uninit_bg flag which set the flags based on all
sorts of special cases. Change it so that it is done in libext2fs,
and fix mke2fs to use alloc_stats functions which will take care of
clearing the *_UNINIT flags automatically as needed.
This is preparatory work to make the flex_bg allocation patch much
cleaner.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Set the s_min_extra_isize and s_wanted_extra_isize superblock fields
to reasonable defaults in ext2fs_initialize().
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>