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.
V2 fields are set on a V1 journal superblock, or an
internal V2 journal has s_nr_users is non-zero, clear the
entire journal superblock beyond the V1 superblock. This
fixes botched V1->V2 updates.
problem.c, problem.h (PR_0_CLEAR_V2_JOURNAL): Add new problem code.
f_bad_local_jnl: New test which tests for a V2 journal with bad
fields caused by a botched V1->V2 upgrade.
Theodore Ts'o