Several small fixes:
* Gracefully fail mmp commands if fs is not open
* Show magic number in dump_mmp command
* Fix header in output for set_mmp_value -l
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Multi-mount protection is feature that allows mke2fs, e2fsck, and
others to detect if the filesystem is mounted on a remote node (on
SAN disks) and avoid corrupting the filesystem. For e2fsprogs this
means that it checks the MMP block to see if the filesystem is in use,
and marks the filesystem busy while e2fsck is running on the system.
This is useful on SAN disks that are shared between high-availability
servers, or accessible by multiple nodes that aren't in HA pairs. MMP
isn't intended to serve as a primary HA exclusion mechanism, but as a
failsafe to protect against user, software, or hardware errors.
There is no requirement that e2fsck updates the MMP block at regular
intervals, but e2fsck does this occasionally to provide useful
information to the sysadmin in case of a detected conflict.
For the kernel (since Linux 3.0) MMP adds a "heartbeat" mechanism to
periodically write to disk (every few seconds by default) to notify
other nodes that the filesystem is still in use and unsafe to modify.
Originally-by: Kalpak Shah <kalpak@clusterfs.com>
Signed-off-by: Johann Lombardi <johann@whamcloud.com>
Signed-off-by: Andreas Dilger <adilger@whamcloud.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 set_fields commands (set_super_value, set_inode_field,
set_block_group) now handle fields which store in split fields on
ext4's on-disk format. For example, the superblock fields
s_blocks_count and s_blocks_count_hi.
The user can either set the low or high part of the field via
"blocks_count_lo" or "blocks_count_hi", or both parts can be set via
"blocks_count".
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reserve EXT4_FEATURE_RO_COMPAT_METADATA_CSUM and
EXT2_FEATURE_COMPAT_EXCLUDE_BITMAP. Also reserve fields in the
superblock and the inode for the checksums. In the block group
descriptor, reserve the exclude bitmap field for the snapshot feature,
and checksums for the inode and block allocation bitmaps.
With this commit, the metadata checksum and exclude bitmap features
should have reserved all of the fields they need in ext4's on-disk
format.
This commit also fixes an a missing byte swap for s_overhead_blocks.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Darrick J. Wong <djwong@us.ibm.com>
Cc: Amir Goldstein <amir73il@gmail.com>
It turns out that it's very hard to calculate overheads in the face of
clustered allocation (bigalloc). This is because multiple metadata
blocks from different block groups can end up in the same allocation
cluster. Calculating the exact overhead requires O(all block bitmaps)
in memory, or O(number of block groups**2) in time. So we will
calculate this at mkfs time and stash it in the superblock.
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>
This patch adds support for detecting the new 'quota' feature in ext4.
The patch reserves code points for usr and group quota inodes and also
for the feature flag EXT4_FEATURE_RO_COMPAT_QUOTA.
Signed-off-by: Aditya Kali <adityakali@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
We also support for byte-swapping the Next3 fields, although the
current Next3 implementation doesn't support big-endian systems.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This field tracks the lifetime amount of writes to the filesystem. It
will be updated by the kernel as well as by e2fsprogs programs which
write to the filesystem.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The l_i_version field is now defined from the old l_i_reserved1 field in
the ext2 inode. This field will be used to store high 32 bits of the
64-bit inode version number.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This command allows the user to set a value in the block group descriptors
for a particular block group.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
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_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>
Generalize the time parsing code and move it to
util.c:string_to_time(). Add new command, set_current_time, which
sets the time used to set the filesystems's time fields.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The set_inodes_field command was silently failing when setting one of
the following fields: frag, fsize, uid_high, gid_high, and author.
The type size for these fields were set to an incorrect value in the
inode_fields table.
fields to be set. For example, to set i_block[2] for the resize inode to
be 42, simply issue the debugfs command:
set_inode <7> block[2] 42
Also added is the virtual field "bmap", which also takes an array index.
So to set the physical block mapping for logical block 1282 in the file
/test/inode to be 57, use the debugfs command:
set_inode /test/inode bmap[1282] 57
lastcheck, and mkfs_time fields with date/time values.
Add the set_inode command to debugfs so that individual inode fields can
be more easily modified. We should probably make the modify_inode
command go away at some point.
Theodore Ts'o