The e2fsprogs and kernel implementation of directory hash tree has a
bug which causes the implementation to be dependent on whether
characters are signed or unsigned. Platforms such as the PowerPC,
Arm, and S/390 have signed characters by default, which means that
hash directories on those systems are incompatible with hash
directories on other systems, such as the x86.
To fix this we add a new flags field to the superblock, and define two
new bits in that field to indicate whether or not the directory should
be signed or unsigned. If the bits are not set, e2fsck and fixed
kernels will set them to the signed/unsigned value of the currently
running platform, and then respect those bits when calculating the
directory hash. This allows compatibility with current filesystems,
as well as allowing cross-architectural compatibility.
Addresses Debian Bug: #389772
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
- EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE (0x0040?) - add s_min_extra_isize and
s_want_extra_isize fields to superblock, which allow specifying
the minimum and desired i_extra_isize fields in large inodes
(for nsec+epoch timestamps, potential other uses). Needs RO_COMPAT
flag handling, needs e2fsck support, patch complete, little testing.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
- EXT4_FEATURE_INCOMPAT_64BIT (0x0080) - support for 64-bit block count
fields in the superblock (s_blocks_count_hi, s_free_blocks_count_hi),
large group descriptors (s_desc_size), extents with high 16 bits
(ee_start_hi, ei_leaf_hi), inode ACL (i_file_acl_hi). May also grow
to encompass the previously proposed BIG_BG.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
- EXT4_FEATURE_RO_COMPAT_DIR_NLINK (0x0020?) - allow directories to have
> 65000 subdirectories (i_nlinks) by setting i_nlinks = 1 for such
directories. RO_COMPAT protects old filesystems from unlinking such
directories incorrectly and losing all files therein.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
- EXT4_FEATURE_RO_COMPAT_GDT_CSUM (0x0010?) - store a crc16 checksum in
the group descriptor (s_uuid[16] | __u32 group | ext3_group_desc
(excluding gd_checksum itself)). This allows the kernel to more safely
manage UNINIT groups.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
- EXT4_FEATURE_RO_COMPAT_HUGE_FILE (0x0008) - change i_blocks to be
in units of s_blocksize units instead of 512-byte sectors, use
l_i_frag and l_i_fsize as i_blocks_hi (could also be part of 64BIT).
E2fsck and debugfs changed to support i_blocks_hi instead of l_i_frag and
l_i_fsize.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This feature is initially intended for testing purposes; it allows an
ext2/ext3 developer to create very large filesystems using sparse files
where most of the block groups are not initialized and so do not require
much disk space. Eventually it could be used as a way of speeding up
mke2fs and e2fsck for large filesystem, but that would be best done by
adding an RO_COMPAT extension to the filesystem to allow the inode table
to be lazily initialized on a per-block basis, instead of being entirely initialized
or entirely unused on a per-blockgroup basis.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Change the maximum allowable blocksize to be 65536. This allows e2fsck to
check filesystems with a pagesize of 65536, and mke2fs to accept -b 65536.
Of course such a filesystem will not currently work on a Linux/x86 system,
at least not as of this writing!
incorrectly treat as valid symlinks created with SE Linux
(Debian bug #228723) as well as failing the f_journal test case on
big endian systems due to the backup journal blocks not being swapped.
superblock. E2fsck will automatically save the journal information
in the superblock if it is not there already, and will use it if the
journal inode appears to be corrupted. ext2fs_add_journal_inode()
will also save the backup information, so that new filesystems
created by mke2fs and filesystems that have journals added via
tune2fs will also have journal location written to the superblock as
well. Debugfs's logdump command has been enhanced so that it can
use the journal information in the superblock.
The debugfs man page has been improved to more fully describe the
logdump command.
Added two new functions, ext2fs_file_open2() and
ext2fs_inode_io_intern2() which take a pointer to an inode structure;
this is needed so that e2fsck and debugfs can synthesize a
fake journal inode and use it to access the journal.
the filesystem was created. It is set via mke2fs, and printed
via list_super2() (which is called by dumpe2fs).
Also, list_super2() will now print "n/a" if the last mount time
(s_mtime) is zero.
a backwards incompatible change, but this should be OK since the kernel
MD4 ext3 code was only in the CVS tree, and hasn't generally escaped.
Add support for the TEA hash.
8192-byte and 16384-byte blocksize filesystems.
Change the default bytes-per-inode ratio of a new filesystem to be at most
one inode per block for large blocksizes.
the EXT2_SB() macro instead. Remove kernel function
prototypes also. This matches the 2.5 kernel, and
is also cleaner for other reasons. Whitespace cleanup.
which signals that a particular inode should not have the
last bits of data (the "tail") be merged with another
file. This is necessary to keep programs like LILO happy.
Makefile.in: Move include/asm/types.h.in to lib/ext2fs/ext2_fs.h.in.
wordwrap.pl: Add some rules which help fix up the dependencies.
Many files:
Move include/asm/types.h.in to lib/ext2fs/ext2_fs.h.in.
ext2_fs.h: Change assignment of EXT2_FEATURE_COMPAT_DIR_INDEX to make
room for pre-existing usage of EXT2_FEATURE_COMPAT_EXT_ATTR. Add flag
EXT2_INDEX_FL with the same codepoint as EXT2_BTREE_FL.
Theodore Ts'o