diff options
Diffstat (limited to 'e2fsprogs/old_e2fsprogs/ext2fs/jfs_dat.h')
-rw-r--r-- | e2fsprogs/old_e2fsprogs/ext2fs/jfs_dat.h | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/e2fsprogs/old_e2fsprogs/ext2fs/jfs_dat.h b/e2fsprogs/old_e2fsprogs/ext2fs/jfs_dat.h new file mode 100644 index 0000000..136635d --- /dev/null +++ b/e2fsprogs/old_e2fsprogs/ext2fs/jfs_dat.h @@ -0,0 +1,65 @@ +/* vi: set sw=4 ts=4: */ +/* + * jfs_dat.h --- stripped down header file which only contains the JFS + * on-disk data structures + */ + +#define JFS_MAGIC_NUMBER 0xc03b3998U /* The first 4 bytes of /dev/random! */ + +/* + * On-disk structures + */ + +/* + * Descriptor block types: + */ + +#define JFS_DESCRIPTOR_BLOCK 1 +#define JFS_COMMIT_BLOCK 2 +#define JFS_SUPERBLOCK 3 + +/* + * Standard header for all descriptor blocks: + */ +typedef struct journal_header_s +{ + __u32 h_magic; + __u32 h_blocktype; + __u32 h_sequence; +} journal_header_t; + + +/* + * The block tag: used to describe a single buffer in the journal + */ +typedef struct journal_block_tag_s +{ + __u32 t_blocknr; /* The on-disk block number */ + __u32 t_flags; /* See below */ +} journal_block_tag_t; + +/* Definitions for the journal tag flags word: */ +#define JFS_FLAG_ESCAPE 1 /* on-disk block is escaped */ +#define JFS_FLAG_SAME_UUID 2 /* block has same uuid as previous */ +#define JFS_FLAG_DELETED 4 /* block deleted by this transaction */ +#define JFS_FLAG_LAST_TAG 8 /* last tag in this descriptor block */ + + +/* + * The journal superblock + */ +typedef struct journal_superblock_s +{ + journal_header_t s_header; + + /* Static information describing the journal */ + __u32 s_blocksize; /* journal device blocksize */ + __u32 s_maxlen; /* total blocks in journal file */ + __u32 s_first; /* first block of log information */ + + /* Dynamic information describing the current state of the log */ + __u32 s_sequence; /* first commit ID expected in log */ + __u32 s_start; /* blocknr of start of log */ + +} journal_superblock_t; + |