/* 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;