/* * This file has definitions for some important file table * structures etc. */#ifndef _FS_H#define _FS_H#include <sys/types.h>/* devices are as follows: (same as minix, so we can use the minix * file system. These are major numbers.) * * 0 - unused (nodev) * 1 - /dev/mem * 2 - /dev/fd * 3 - /dev/hd * 4 - /dev/ttyx * 5 - /dev/tty * 6 - /dev/lp * 7 - unnamed pipes */#define IS_SEEKABLE(x) ((x)>=1 && (x)<=3)#define READ 0#define WRITE 1#define READA 2		/* read-ahead - don't pause */void buffer_init(long buffer_end);#define MAJOR(a) (((unsigned)(a))>>8)#define MINOR(a) ((a)&0xff)#define NAME_LEN 14#define ROOT_INO 1#define I_MAP_SLOTS 8#define Z_MAP_SLOTS 8#define SUPER_MAGIC 0x137F#define NR_OPEN 20#define NR_INODE 32#define NR_FILE 64#define NR_SUPER 8#define NR_HASH 307#define NR_BUFFERS nr_buffers#define BLOCK_SIZE 1024#define BLOCK_SIZE_BITS 10#ifndef NULL#define NULL ((void *) 0)#endif#define INODES_PER_BLOCK ((BLOCK_SIZE)/(sizeof (struct d_inode)))#define DIR_ENTRIES_PER_BLOCK ((BLOCK_SIZE)/(sizeof (struct dir_entry)))#define PIPE_HEAD(inode) ((inode).i_zone[0])#define PIPE_TAIL(inode) ((inode).i_zone[1])#define PIPE_SIZE(inode) ((PIPE_HEAD(inode)-PIPE_TAIL(inode))&(PAGE_SIZE-1))#define PIPE_EMPTY(inode) (PIPE_HEAD(inode)==PIPE_TAIL(inode))#define PIPE_FULL(inode) (PIPE_SIZE(inode)==(PAGE_SIZE-1))#define INC_PIPE(head) \__asm__("incl %0\n\tandl $4095,%0"::"m" (head))typedef char buffer_block[BLOCK_SIZE];struct buffer_head {	char * b_data;			/* pointer to data block (1024 bytes) */	unsigned short b_dev;		/* device (0 = free) */	unsigned short b_blocknr;	/* block number */	unsigned char b_uptodate;	unsigned char b_dirt;		/* 0-clean,1-dirty */	unsigned char b_count;		/* users using this block */	unsigned char b_lock;		/* 0 - ok, 1 -locked */	struct task_struct * b_wait;	struct buffer_head * b_prev;	struct buffer_head * b_next;	struct buffer_head * b_prev_free;	struct buffer_head * b_next_free;};struct d_inode {	unsigned short i_mode;	unsigned short i_uid;	unsigned long i_size;	unsigned long i_time;	unsigned char i_gid;	unsigned char i_nlinks;	unsigned short i_zone[9];};struct m_inode {	unsigned short i_mode;	unsigned short i_uid;	unsigned long i_size;	unsigned long i_mtime;	unsigned char i_gid;	unsigned char i_nlinks;	unsigned short i_zone[9];/* these are in memory also */	struct task_struct * i_wait;	unsigned long i_atime;	unsigned long i_ctime;	unsigned short i_dev;	unsigned short i_num;	unsigned short i_count;	unsigned char i_lock;	unsigned char i_dirt;	unsigned char i_pipe;	unsigned char i_mount;	unsigned char i_seek;	unsigned char i_update;};struct file {	unsigned short f_mode;	unsigned short f_flags;	unsigned short f_count;	struct m_inode * f_inode;	off_t f_pos;};struct super_block {	unsigned short s_ninodes;	unsigned short s_nzones;	unsigned short s_imap_blocks;	unsigned short s_zmap_blocks;	unsigned short s_firstdatazone;	unsigned short s_log_zone_size;	unsigned long s_max_size;	unsigned short s_magic;/* These are only in memory */	struct buffer_head * s_imap[8];	struct buffer_head * s_zmap[8];	unsigned short s_dev;	struct m_inode * s_isup;	struct m_inode * s_imount;	unsigned long s_time;	struct task_struct * s_wait;	unsigned char s_lock;	unsigned char s_rd_only;	unsigned char s_dirt;};struct d_super_block {	unsigned short s_ninodes;	unsigned short s_nzones;	unsigned short s_imap_blocks;	unsigned short s_zmap_blocks;	unsigned short s_firstdatazone;	unsigned short s_log_zone_size;	unsigned long s_max_size;	unsigned short s_magic;};struct dir_entry {	unsigned short inode;	char name[NAME_LEN];};extern struct m_inode inode_table[NR_INODE];extern struct file file_table[NR_FILE];extern struct super_block super_block[NR_SUPER];extern struct buffer_head * start_buffer;extern int nr_buffers;extern void check_disk_change(int dev);extern int floppy_change(unsigned int nr);extern int ticks_to_floppy_on(unsigned int dev);extern void floppy_on(unsigned int dev);extern void floppy_off(unsigned int dev);extern void truncate(struct m_inode * inode);extern void sync_inodes(void);extern void wait_on(struct m_inode * inode);extern int bmap(struct m_inode * inode,int block);extern int create_block(struct m_inode * inode,int block);extern struct m_inode * namei(const char * pathname);extern int open_namei(const char * pathname, int flag, int mode,	struct m_inode ** res_inode);extern void iput(struct m_inode * inode);extern struct m_inode * iget(int dev,int nr);extern struct m_inode * get_empty_inode(void);extern struct m_inode * get_pipe_inode(void);extern struct buffer_head * get_hash_table(int dev, int block);extern struct buffer_head * getblk(int dev, int block);extern void ll_rw_block(int rw, struct buffer_head * bh);extern void brelse(struct buffer_head * buf);extern struct buffer_head * bread(int dev,int block);extern struct buffer_head * breada(int dev,int block,...);extern int new_block(int dev);extern void free_block(int dev, int block);extern struct m_inode * new_inode(int dev);extern void free_inode(struct m_inode * inode);extern int sync_dev(int dev);extern struct super_block * get_super(int dev);extern int ROOT_DEV;extern void mount_root(void);#endif